PRODUCTION CHEMICALS FOR THE OIL AND GAS INDUSTRY PDF DOWNLOAD

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HYDROCARBON EXPLORATION PRODUCTION

HYDROCARBON EXPLORATION PRODUCTION

‘Hydrocarbon Exploration and Production’ takes the reader through all the major stages in the
life of an oil or gas field, from gaining access to opportunity, through exploration, appraisal,
development planning, production and finally to decommissioning. It straightforwardly
explains the fiscal and commercial environment in which oil and gas field development takes
place.
This comprehensive and current introduction to the upstream industry, is useful to industry
professionals who wish to be better informed about the basic technical and commercial
methods, concepts and techniques used. It is also intended for readers who provide support
services to the upstream industry.
It draws together the many interdisciplinary links within the industry in a clear and
concise manner, while pointing out the commercial reason for the activities involved in the
business – each chapter is introduced by pointing out the commercial application of the
subject. The many illustrations are clear and plentiful, and are designed to maximise the
learning while containing the detail necessary to preserve technical authenticity.
The authors are all practising consultants in the business, and have included the major
advances in the industry in this latest edition, including technical methods for field
evaluation and development and techniques used for managing risk within the business.
TRACS International has provided training and consultancy in Exploration and Production
related issues for many clients worldwide since 1992. This book has gradually developed from
course materials, discussions with clients and material available in the public domain.
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Approach to Zero Emission Processes in Food Industry - Case Study for Soy-Sauce Production Process -

APPROACH TO ZERO EMISSION PROCESSES IN FOOD INDUSTRY - CASE STUDY FOR SOY-SAUCE PRODUCTION PROCESS -

The material flow in soy-sauce production process was analyzed for total mass, TOC, T-N,
T-P and T-Cl. A main solid emission from the process was lees, a cake after filtration of
fermented broth. The various reutilization method of the lees as a resource was studied and the
dry distillation was investigated in detail. The conversion of lees by dry distillation increased
with temperature rapidly at low temperature, but moderately at high temperature region. The
production of inflammable gases was prominent at high temperature. The liquid products
obtained during the condensation of exit gas were composed of aqueous and organic solutions.
The solid residue was a char like a fiber containing inorganic phosphorus compounds which was
not removed by washing. The reusing method of these products was discussed.
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LIPIDS, FATS, AND OILS

LIPIDS, FATS, AND OILS

131
5 Lipids, Fats, and Oils
Ioannis S. Arvanitoyannis, Theodoros H. Varzakas,
Sotirios Kiokias, and Athanasios E. Labropoulos
CONTENTS
5.1 Introduction .......................................................................................................................... 132
5.1.1 Fatty Acids ................................................................................................................ 133
5.1.2 Saturated Fatty Acids................................................................................................ 133
5.1.3 Unsaturated Fatty Acids ........................................................................................... 134
5.1.4 Acylglycerols ............................................................................................................ 134
5.2 Major Oils and Fats .............................................................................................................. 134
5.2.1 Oils and Fats of Vegetable Origin ............................................................................ 139
5.2.1.1 Olive Oil ..................................................................................................... 139
5.2.1.2 Corn Oil ..................................................................................................... 139
5.2.1.3 Soybean Oil ................................................................................................ 139
5.2.1.4 Sunfl ower Oil ............................................................................................. 142
5.2.1.5 Cottonseed Oil ........................................................................................... 142
5.2.1.6 Wheat Germ Oil ........................................................................................ 142
5.2.1.7 Rapeseed or Canola Oil ............................................................................. 143
5.2.1.8 Palm and Palm Kernel Oil ......................................................................... 143
5.2.1.9 Saffl ower Oil .............................................................................................. 144
5.2.1.10 Coconut Oil ................................................................................................ 144
5.2.1.11 Cocoa Butter .............................................................................................. 144
5.2.1.12 Sesame Oil ................................................................................................. 145
5.2.2 Oils and Fats of Animal Origin ................................................................................ 145
5.2.2.1 Butter .......................................................................................................... 145
5.2.2.2 Lard ............................................................................................................ 146
5.2.2.3 Tallow......................................................................................................... 146
5.2.2.4 Ghee ........................................................................................................... 146
5.2.2.5 Fish Oil ...................................................................................................... 147
5.3 Physical Parameters .............................................................................................................. 148
5.3.1 Crystallization, Melting Point, and Polymorphism .................................................. 148
5.3.1.1 Crystallization ............................................................................................ 148
5.3.1.2 Melting Point .............................................................................................. 149
5.3.1.3 Polymorphism ............................................................................................ 149
5.3.2 Density, Viscosity, and Refractive Index .................................................................. 149
5.3.2.1 Density ....................................................................................................... 149
5.3.2.2 Viscosity..................................................................................................... 150
5.3.2.3 Refractive Index ......................................................................................... 150
5.4 Chemical Parameters ............................................................................................................ 150
5.4.1 Oxidation .................................................................................................................. 150
132 Advances in Food Biochemistry
5.4.1.1 Autoxidation ............................................................................................... 150
5.4.1.2 AzoInitiated Oxidation ............................................................................. 151
5.4.1.3 Photosensitized Oxidation ......................................................................... 151
5.4.1.4 Metal Catalyzed Oxidation ........................................................................ 152
5.4.1.5 Enzyme Catalyzed Oxidation .................................................................... 152
5.4.1.6 Decomposition of Hydroperoxides ............................................................ 153
5.4.1.7 Physical Aspects—Lipid Oxidation in Food Emulsions ........................... 153
5.4.2 Antioxidant Activity of Carotenoids......................................................................... 154
5.4.2.1 Carotenoids as Radical Scavengers—Mechanism of
Antioxidant Action ..................................................................................... 154
5.4.2.2 Reactivity of Carotenoids Toward Free Radicals—Effect of
Structure on Scavenging Activity .............................................................. 155
5.4.2.3 Oxidative Degradation of Carotenoids by Free Radicals .......................... 156
5.4.2.4 Oxygen Quenching Activity of Carotenoids on OilPhotooxidation ......... 156
5.4.3 Natural Antioxidants Tested ..................................................................................... 157
5.4.3.1 Tocopherols and Tocotrienols .................................................................... 157
5.4.3.2 Ascorbic Acid and Ascorbyl Palmitate ...................................................... 159
5.4.3.3 OliveOil Phenolics .................................................................................... 160
5.5 Legislation for Oils and Fats ................................................................................................. 161
5.5.1 EU Legislation for Oils and Fats .............................................................................. 161
5.5.2 U.S. Legislation Related to Oil ................................................................................. 162
5.5.3 Canada Legislation Focused on Oil .......................................................................... 165
5.6 Authenticity of Oils and Fats ................................................................................................ 166
5.6.1 Authenticity of Vegetable Oils and Fats ................................................................... 166
5.6.1.1 Olive Oil Authenticity ................................................................................ 166
5.6.1.2 Maize Oil Authenticity .............................................................................. 181
5.6.1.3 Rapeseed Oil Authenticity ......................................................................... 181
5.6.1.4 Sesame Oil Authenticity ............................................................................ 181
5.6.1.5 Mustard Oil Authenticity ........................................................................... 182
5.6.1.6 Cocoa Butter Authenticity ......................................................................... 182
5.6.1.7 Palm, Palm Kernel, and Coconut Oils Authenticity .................................. 183
5.6.2 Authenticity of Animal Oils and Fats ....................................................................... 183
5.6.2.1 Butter Authenticity ..................................................................................... 184
5.6.2.2 Lard Authenticity ....................................................................................... 184
5.7 Functional and Health Properties of Fats and Oils in Foods ................................................ 185
5.7.1 Functional Issues ...................................................................................................... 185
5.7.2 Health Issues ............................................................................................................. 187
5.7.3 Process and Application Issues ................................................................................. 189
5.7.3.1 Shortenings “Puff Pastry” and Margarines ............................................... 189
5.7.3.2 Baker’s Margarines .................................................................................... 189
5.7.3.3 Pie’s Shortenings ........................................................................................ 189
References ...................................................................................................................................... 190
5.1 INTRODUCTION
Lipids consist of a broad group of compounds that are generally soluble in organic solvents but
only sparingly soluble in water. They are major components of adipose tissue, and together with
proteins and carbohydrates, they constitute the principal structural components of all living cells.
Glycerol esters of fatty acids, which make up to 99% of the lipids of plant and animal origin, have
been traditionally called fats and oils.1 The difference between oils and fats is that fats are solids at
room temperatures.2
Lipids, Fats, and Oils 133
The majority of lipids are derivatives of fatty acids. In these socalled acyl lipids, the fatty acids
are present as esters, and in some minor lipid groups in amide forms (Table 5.1). The acyl residue
infl uences strongly the hydrophobicity and the reactivity of the acyl lipids. Some lipids act as building
blocks in the formation of biological membranes, which surround cells and subcellular particles.
Primarily, triacylglycerols are deposited in some animal tissues and organs of some plants. Lipid
content in such storage tissues can rise to 15%–20% or higher and so serve as a commercial source
for isolation of triacylglycerols.3
5.1.1 FATTY ACIDS
Fatty acid is a carboxylic acid often with a long, unbranched aliphatic chain, which is either saturated
or unsaturated. Carboxylic acids as short as butyric acid (four carbon atoms) are considered
to be fatty acids, whereas fatty acids derived from natural fats and oils may be assumed to have
at least eight carbon atoms, e.g., caprylic acid (octanoic acid). Fatty acids are aliphatic monocarboxylic
acids derived from or contained in an esterifi ed form in an animal or vegetable fat, oil, or
wax. Natural fatty acids commonly have a chain of 4–28 carbons (usually unbranched and even
numbered), which may be saturated or unsaturated. By extension, the term is sometimes used to
embrace all acyclic aliphatic carboxylic acids.4
5.1.2 SATURATED FATTY ACIDS
Saturated fatty acids do not contain any double bonds or other functional groups along the chain.
The term “saturated” refers to hydrogen, in that all carbons (apart from the carboxylic acid –COOH
group) contain as many hydrogens as possible. Saturated fatty acids form straight chains and, as a
result, can be packed together very tightly, allowing living organisms to store chemical energy very
densely. The fatty tissues of animals contain large amounts of longchain saturated fatty acids.5
Fatty acids have an “oic” suffi x to the name of the acid but the suffi x is usually “ic.” The shortest
descriptions of fatty acids include only the number of carbon atoms and double bonds in them
TABLE 5.1
Lipid Classifi cation
Classifi cation Categories Characteristics
Acyl residue Simple lipids (not saponifi able)
Free fatty acids —
Isoprenoid lipids Steroids, carotenoids, monoterpenes
Tocopherols —
Acyl lipids (saponifi able)
Mono, di, triacylglycerols Fatty acids, glycerol
Phospholipids (phosphatides) Fatty acids, glycerol or sphingosine,
phosphoric acid, organic base
Glycolipids Fatty acids, glycerol or sphingosine,
mono, di, or oligosaccharide
Diol lipids Fatty acids, ethane, propane, or butane diol
Waxes Fatty acids, fatty alcohol
Sterol esters Fatty acids, sterol
Neutralpolar Glycerophospholipids Fatty acids (>C12)
Glyceroglycolipids Mono, di, or triacylglycerols
Sphingophospholipids Sterols, sterol esters
Sphingoglycolipids Carotenoids, waxes, tocopherols
134 Advances in Food Biochemistry
(e.g., C18:0 or 18:0). C18:0 means that the carbon chain of the fatty acid consists of 18 carbon atoms,
and there are no (zero) double bonds in it, whereas C18:1 describes an 18carbon chain with one
double bond in it. Each double bond can be in either a cis or trans conformation and in a different
position with respect to the ends of the fatty acid; therefore, not all C18:1s, for example, are identical.
If there are one or more double bonds in the fatty acid, it is no longer considered saturated, but rather
mono or polyunsaturated.6 The characteristics of saturated fatty acids are given in Table 5.2.
5.1.3 UNSATURATED FATTY ACIDS
Unsaturated fatty acids are of similar form, except that one or more allyl functional groups exist
along the chain, with each alkene substituting a singlebonded “–CH2–CH2–” part of the chain with
a doublebonded “–CH=CH–” portion. The two next carbon atoms in the chain that are bound to
either side of the double bond can occur in a cis or trans confi guration.7
A cis confi guration means that adjacent carbon atoms are on the same side of the double bond.
The rigidity of the double bond freezes its conformation and, in the case of the cis isomer, causes
the chain to bend and restricts the conformational freedom of the fatty acid. The more double bonds
the chain has in the cis confi guration, the less fl exibility it has. When a chain has many cis bonds, it
becomes quite curved in its most accessible conformations.8 For example, oleic acid has one double
bond, and linoleic acid with two double bonds has a more pronounced bend. αLinolenic acid, with
three double bonds, favors a hooked shape. The effect of this is that in restricted environments, such
as when fatty acids are part of a phospholipid in a lipid bilayer, or triglycerides in lipid droplets,
cis bonds limit the ability of fatty acids to be closely packed, and therefore could affect the melting
temperature of the membrane or of the fat.9
A trans confi guration, by contrast, means that the next two carbon atoms are bound to opposite
sides of the double bond. As a result, they do not cause the chain to bend much, and their shape is
similar to straight saturated fatty acids.10 In most naturally occurring unsaturated fatty acids, each
double bond has 3n carbon atoms after it, for some n, and all are cis bonds. Most fatty acids in the
trans confi guration (trans fats) are not found in nature and are the result of human processing. The
differences in geometry between the various types of unsaturated fatty acids, as well as between
saturated and unsaturated fatty acids, play an important role in biological processes, and in the
construction of biological structures (such as cell membranes).11 The characteristics of unsaturated
fatty acids are given in Table 5.3.
5.1.4 ACYLGLYCEROLS
Neutral fats are mono, di, and triesters of glycerol with fatty acids, and are termed monoacylglycerols,
diacylglycerols, and triacylglycerols, respectively. They are designated as neutral lipids.
Edible oils or fats consist nearly completely of triacylglycerols.3 Although glycerol by itself is a
completely symmetrical molecule, the central carbon atom acquires chirality (asymmetry) if one
of the primary hydroxyl groups (on carbons 1–3) is esterifi ed, or if the two primary hydroxyls are
esterifi ed to different acids.1
5.2 MAJOR OILS AND FATS
All oils and fats, with their high carbon and hydrogen content, can be traced back to organic
sources. Oils and fats are also produced by plants, animals, and other organisms through organic
processes and these oils are remarkable in their diversity.12 Oils are fats that are liquids at room
temperature. Solid fats are fats that are solids at room temperature, like butter and shortening. Solid
fats come from many animal foods and can be made from vegetable oils through a process called
hydrogenation.13
Lipids, Fats, and Oils 135
TABLE 5.2
Saturated Fatty Acids
IUPAC Name Common Name Abbreviation Chemical Structure Structure Melting Point (°C)
Butanoic acid Butyric acid 4:0 CH3(CH2)2COOH O
OH
−7.9
Pentanoic acid Valeric acid 5:0 CH3(CH2)3COOH
OH
O −34.5
Hexanoic acid Caproic acid 6:0 CH3(CH2)4COOH O
OH
−3.9
Heptanoic acid Enanthic acid 7:0 CH3(CH2)5COOH O
OH
−7.5
Octanoic acid Caprylic acid 8:0 CH3(CH2)6COOH O
OH
16.3
Nonanoic acid Pelargonic acid 9:0 CH3(CH2)7COOH O
OH
12.4
Decanoic acid Capric acid 10:0 CH3(CH2)8COOH O
OH
31.3
Dodecanoic acid Lauric acid 12:0 CH3(CH2)10COOH O
OH
44
Tetradecanoic acid Myristic acid 14:0 CH3(CH2)12COOH O
OH
54.4
Hexadecanoic acid Palmitic acid 16:0 CH3(CH2)14COOH O
OH
62.9
(continued)
136 Advances in Food Biochemistry
TABLE 5.2 (continued)
Saturated Fatty Acids
IUPAC Name Common Name Abbreviation Chemical Structure Structure Melting Point (°C)
Heptadecanoic acid Margaric acid 17:0 CH3(CH2)15COOH O OH 61.3
Octadecanoic acid Stearic acid 18:0 CH3(CH2)16COOH O
OH
69.6
Eicosanoic acid Arachidic acid 20:0 CH3(CH2)18COOH
O
O
H
75.4
Docosanoic acid Behenic acid 22:0 CH3(CH2)20COOH
CH3
O
HO 80.0
Tetracosanoic acid Lignoceric acid 24:0 CH3(CH2)22COOH COOH 84.2
Hexacosanoic acid Cerotic acid 26:0 CH3(CH2)24COOH O OH 87.7
Lipids, Fats, and Oils 137
TABLE 5.3
Unsaturated Fatty Acids
Common Name Abbreviation Chemical Structure Structure Family (w) Family (D) Melting Point (°C)
Myristoleic acid 14:1 CH3(CH2)3CH=CH(CH2)7COOH O
OH
ω5 cisΔ9 —
Palmitoleic acid 16:1 CH3(CH2)5CH=CH(CH2)7COOH O
OH
ω7 cisΔ9 0.1
Oleic acid 18:1 CH3(CH2)7CH=CH(CH2)7COOH O
OH
ω9 cisΔ9 13.4
Linoleic acid 18:2 CH3(CH2)4CH=CHCH2CH=CH
(CH2)7COOH
O
1 9 12
6 1
HO
ω ω6 cis, cisΔ9, Δ12 −5
αLinolenic acid 18:3 CH3CH2CH=CHCH2CH=CHCH2
CH=CH(CH2)7COOH
O
α
ω
HO1 9
9 6 3 1
12 15 18
ω3 cis, cis, cisΔ9,
Δ12, Δ15
−11
γLinolenic acid 18:3 (CH=CHCH2)3CH2CH2CH2COOH O
HO
1 6 9 12
6 1
ω ω6 cis, cis, cisΔ6,
Δ9, Δ12

Arachidonic acid 20:4 CH3(CH2)4CH=CHCH2CH=CHCH2
CH=CHCH2CH=CH(CH2)3COOH
O
HO1 5 8 11 14
6 1
ω ω6 cis, cis, cis, cis
Δ5, Δ8, Δ11, Δ14
−49.5
Eicosapentaenoic
acid (EPA)
20:5 CH3CH2CH=CHCH2CH=CH
CH2CH=CHCH2CH=CHCH2
CH=CH(CH2)3COOH
1 5 8 11 14 17 20
6 3 1
O
HO
ω
α
ω3 cis, cis, cis, cis,
cisΔ5, Δ8, Δ11,
Δ14, Δ17

(continued)
138 Advances in Food Biochemistry
TABLE 5.3 (continued)
Unsaturated Fatty Acids
Common Name Abbreviation Chemical Structure Structure Family (w) Family (D) Melting Point (°C)
Erucic acid 22:1 CH3(CH2)7CH=CH(CH2)11COOH O
OH
ω9 cisΔ13 34.7
Docosahexaenoic
acid (DHA)
22:6 CH3CH2CH=CHCH2CH=CHCH2
CH=CHCH2CH=CHCH2CH=CH
CH2CH=CH(CH2)2COOH 1 4 7 10 13 16 19
3 1
HO
O
ω ω3 cis, cis, cis, cis,
cis, cisΔ5, Δ8,
Δ11, Δ14, Δ17

Nervonic acid 24:1 (CH2)12COOH O
OH
ω9 cisΔ15 42.5
Lipids, Fats, and Oils 139
5.2.1 OILS AND FATS OF VEGETABLE ORIGIN
The vegetable oils may be subdivided into three categories: (1) byproducts, where the crop is
grown for another purpose other than seed oil, e.g., cotton (fabric), (2) three crops, which are generally
slow to mature but then produce crops regularly for many years (olive, palm, and coconut),
(3) crops, which have to be replanted each year to produce an annual harvest and where decisions
about cultivation are made each sowing season by a large number of individual farmers (rape, sunfl
ower, sesame, etc.).14 Typical fatty acid compositions of vegetable oils and fats are summarized
in Table 5.4.
5.2.1.1 Olive Oil
Over 750 million olive trees are cultivated worldwide, about 95% of those in the Mediterranean
region. Most of the global production comes from Southern Europe, North Africa, and the Middle
East. Of the European production, 93% comes from Spain, Italy, Turkey, and Greece. Spain’s production
alone accounts for 40%–45% of the world production, which was 2.6 million metric tons in
2002.15 In olive oil–producing countries, the local production is generally considered the fi nest.
The olive oil extraction is carried out with technological industrial processes (continuous or discontinuous),
even though the quality and the quantity of the obtained oil are still to be optimized.16
The most traditional way of making olive oil is by grinding olives. Green olives produce bitter oil
and overly ripened olives produce rancid oil, so care is taken to make sure the olives are perfectly
ripened. First, the olives are ground into an olive paste using large mills. The olive paste generally
stays under the mills for 30–40 min. The oil collected during this part of the process is called
virgin oil. After grinding, the olive paste is spread on fi ber disks, which are stacked on top of each
other, and then placed into the press. Pressure is then applied onto the disk to further separate the
oil from the paste. This second step produces a lower grade of oil.17 The production of olive oil is
shown in Figure 5.1.
The oil is characterized by a high level of oleic acid with Codex ranges of 8%–20% for palmitic
acid, 55%–83% for oleic acid and 4%–21% for linoleic acid.18 Extra virgin olive oil has a perfect
fl avor and odor with a maximum acidity of 1% (as oleic acid). Fine virgin oil also has a perfect fl avor
and odor with a maximum acidity of 2%. Semifi ne or ordinary virgin oil has good fl avor and odor
and a maximum acidity of 3.3% with a 10% margin of tolerance. Virgin olive oil with an offfl avor
or offodor and acidity >3.3% is designated lampante. Refi ned olive oil, obtained from virgin olive
oil by refi ning methods which do not affect fatty acid or glycerol ester composition, should have
acidity <0.5%.19
5.2.1.2 Corn Oil
Corn oil is oil extracted from the germ of corn (maize). Its main use is in cooking, where its high
smoke point makes it a valuable frying oil. It is also a key ingredient in some margarines. Corn oil
has a milder taste and is less expensive than most other types of vegetable oils.20
A major vegetable oil, with a production of around 2 million tonnes per annum from maize (Zea
mays), is obtained by wet milling, particularly in the United States. The major acids are palmitic
(9%–17%), oleic (20%–42%), and linoleic (39%–63%), and the major triacylglycerols.21 Refi ned
corn oil is 99% triglyceride, with proportions of approximately 59% polyunsaturated fatty acid,
24% monounsaturated fatty acid, and 13% saturated fatty acid.22
5.2.1.3 Soybean Oil
The soybean or soya bean (Glycine max) is a species of legume native to East Asia. In processing
soybeans for oil extraction, selection of high quality, sound, clean, dehulled, yellow soybeans is very
important. To produce soybean oil, the soybeans are cracked, adjusted for moisture content, rolled
into fl akes, and solventextracted with commercial hexane. The oil is then refi ned, blended for different
applications, and sometimes hydrogenated.23 In the past, hydrogenation was used to reduce
140 Advances in Food Biochemistry
TABLE 5.4
Typical Fatty Acid Composition of the Main Vegetable Oils and Fats
Kind of Vegetable
Oil and Fats
Fatty Acids
Saturated
(g100 g)
Monounsaturated
(g100 g)
Polyunsaturated
(g100 g) 16:1 (wt%) 18:0 (wt%) 18:1 (wt%) 18:2 (wt%) 18:3 (wt%)
Olive oil 14.0 69.7 11.2 10 2 78 7 1
Corn oil 12.7 24.7 57.8 13 3 31 52 1
Soybean oil 14.5 23.2 56.5 11 4 23 53 8
Sunfl ower oil 11.9 20.2 63.0 6 5 20 60 —
Cottonseed oil 25.5 21.3 48.1 23 2 17 56 —
Wheat germ oil 18.8 15.9 60.7 16 2 14 60 5
Rapeseedcanola oil 5.3 64.3 24.8 3 1 16 14 10
Palm oil 45.3 41.6 8.3 41 4 31 12 —
Saffl ower oil 10.2 12.6 72.1 7 3 14 75 —
Coconut oil 85.2 6.6 1.7 81 4 5 1 —
Cocoa butter 24.2 21.7 48.9 26 34 20 43 —
Sesame oil 16.4 40.1 42.5 10 4 46 46 —
Sources: Gunstone, F.D., The Chemistry of Oils and Fats—Sources, Composition, Properties and Uses, CRC Press, Boca Raton, FL, p. 7, 2004; FSA (Food Standards Agency),
Fats and oils, McCance and Widdowson’s the Composition of Foods, 5th edn, Royal Society of Chemistry, Cambridge, U.K., 1991; Altar, T., More than you wanted to
know about fatsoils, Sundance Natural Foods, 1995, Available at: http:www.efn.org∼sundancefats_and_oils.html (accessed 2022008).
Lipids, Fats, and Oils 141
the unsaturation in linolenic acid, but this produced an unnatural trans fatty acid, having a trans fat
confi guration, whereas in nature the confi guration is cis.24
The seed oil contains palmitic (about 11%, range 7%–14%), oleic (about 20%, range 19%–30%),
linoleic (about 53%, range 44%–62%), and linolenic acids (about 7%, range 4%–11%). It also contains
the saturated fatty acids: 4% stearic acid and 10% palmitic acid.25
Receipt of
olives
Transport to
oilmill
Olive storage
Defoliation
Washing
Olives grinding
Receipt of olive
pomace
Final separation
of olive oil
Receipt of olive oil
Remotion of
muckoid substances
Nutralization of free
fatty acid
Cleaning
Bleaching
Packaging
Storage
Distribution
Receipt of
packaging
materials
Storage of packaging
materials
Refinement
Water
remotion
Olive
leaves
remotion
Water
Olive
kernel
remotion
FIGURE 5.1 Flow diagram of olive oil production.
142 Advances in Food Biochemistry
After suitable modifi cation it can be used as a solvent, a lubricant, and as biodiesel. Valuable
byproducts recovered during refi ning include lecithin, tocopherols, and phytosterols. Attempts to
modify the fatty acid composition by seed breeding or genetic modifi cation are directed to reducing
the level of saturated acid or linolenic acid, or increasing the content of stearic acid.26
In the 2002–2003 growing season, 30.6 million metric tons of soybean oil were produced
worldwide, constituting about half of the worldwide edible vegetable oil production, and thirty
percent of all fats and oils produced, including animal fats and oils derived from tropical plants.15
Soybean oil is produced in larger amounts than any other traded oil (about 23 million tonnes a year)
and is grown particularly in the United States, followed by Brazil, Argentina, and China.25
5.2.1.4 Sunfl ower Oil
Sunfl ower oil is the nonvolatile oil expressed from sunfl ower (Helianthus annuus) seeds. A major
vegetable oil (about 9 million tonnes per annum), it is extracted from the seed of Helianthus annuus
grown mainly in the USSR, Argentina, Western and Eastern Europe, China, and the United
States.26 Sunfl ower oil is commonly used in food as frying oil, and in cosmetic formulations as an
emollient.
Sunfl ower oil contains predominantly linoleic acid in triglyceride form. The British Pharmacopoeia
lists the following profi le: palmitic acid (4%–9%), stearic acid (1%–7%), oleic acid (14%–40%), linoleic
acid (48%–74%).27 There are several types of sunfl ower oils produced, such as high linoleic,
high oleic, and mid oleic. High linoleic sunfl ower oil typically has at least 69% linoleic acid. High
oleic sunfl ower oil has at least 82% oleic acid. Variation in fatty acid profi le is strongly infl uenced by
both genetics and climate. Sunfl ower oil also contains lecithin, tocopherols, carotenoids, and waxes.
Sunfl ower oil’s properties are typical of vegetable triglyceride oil.18 Higholeic varieties (Sunola or
Highsun, NuSun) with about 85% and 60% oleic acid have been developed and fi nd use as sources
of oleic acid in enzymatically modifi ed products.28
5.2.1.5 Cottonseed Oil
Cottonseed oil is a vegetable oil extracted from the seeds of the cotton plant after the cotton lint has
been removed. It must be refi ned to remove gossypol, a naturally occurring toxin that protects the
cotton plant from insect damage.29 In its natural unhydrogenated state, cottonseed oil, like all vegetable
oils, has no cholesterol. It also contains no trans fatty acids. Further, these polyunsaturated
fats can potentially go rancid during the extraction process.30
A major vegetable oil (4 million tonnes per annum) obtained as a byproduct in the production of
cotton and grown mainly in China, the United States, the USSR, India, and Pakistan. It ranks fi fth
among vegetable oils. Cottonseed oil is rich in palmitic acid (22%–26%), oleic acid (15%–20%), and
linoleic acid (49%–58%), and contains a 10% mixture of arachidic acid, behenic acid, and lignoceric
acid. It also contains about 1% sterulic and malvalic acids in the crude oil. The latter are identifi
ed by the Halphen test. The cyclopropene acids are undesirable components, but they are largely
removed during refi ning, particularly deodorization, and also during hydrogenation. They are not
considered to present any health hazard in cottonseed oil.31
5.2.1.6 Wheat Germ Oil
Wheat germ oil is extracted from the germ of the wheat kernel, which makes up only 2.5% by
weight of the kernel. Wheat germ oil is particularly high in octacosanol—a 28 carbon longchain
saturated primary alcohol found in a number of different vegetable waxes. Octacosanol has been
studied as an exerciseenhancing and a physical performance–enhancing agent. As a cooking oil,
wheat germ oil is strongly fl avored, expensive, and easily perishable.32
Oil from wheat germ (the embryo of the seed of Triticum aestivum) is rich in linoleic acid (ca.
60%), also contains αlinolenic acid (ca. 5%), 16% palmitic acid, and 14% oleic acid. The oil is rich
in tocopherols and shows high vitamin E activity.18
Lipids, Fats, and Oils 143
5.2.1.7 Rapeseed or Canola Oil
Canola or rapeseed (Brassica napus or B. campestris) is a bright yellowfl owering member of the
Brassicaceae (also known as the mustard) family. It is cultivated for the production of animal feed,
vegetable oil for human consumption, and biodiesel. Worldwide, canola was the third leading source
of vegetable oil in 2000, after soy and palm oils. Canola is also the world’s second leading source
of protein meal.33
Typically, this oil was rich in erucic acid, which is still available from higherucic rapeseed
oil (HEAR) or from crambe oil. Erucic acid is mildly toxic to humans in large doses but is used
as a food additive in smaller doses. The variety low in erucic acid (<5% or <2%) and also in glucosinolates
(LEAR, double zero) is now more important. The oil typically contains palmitic (4%),
stearic (2%), oleic (56%), linoleic (26%), and linolenic acids (10%).34 Rapeseed lends itself to genetic
manipulation and rapeseed oil containing a lower level of linolenic acid or higher levels of lauric,
stearic, or oleic acid or new acids, such as δlinolenic, ricinoleic, or vernolic acids, are being developed
for commercial exploitation.18
Canada and the United States produce between 7 and 10 million metric tons of canola seed per
year.34 Annual Canadian exports total 3–4 million metric tons of the seed, 700,000 metric tons
of canola oil, and 1 million metric tons of canola meal. The United States is the net consumer of
canola oil. The major customers of canola seed are Japan, Mexico, China, and Pakistan, while the
bulk of canola oil and meal goes to the United States, with smaller amounts shipped to Taiwan,
Mexico, China, and Europe. The world production of rapeseed oil in 2002–2003 was about 14
million metric tons.15
5.2.1.8 Palm and Palm Kernel Oil
Palm oil is a form of edible vegetable oil obtained from the fruit of the oil palm tree (Elaeis guineensis).
The palm fruit is the source of both palm oil (extracted from palm fruit) and palm kernel oil
(extracted from the fruit seeds). Palm oil itself is reddish because it contains a high amount of
βcarotene. It is used as a cooking oil, to make margarine, and is a component of many processed
foods.35 Boiling it for a few minutes destroys the carotenoids, and the oil becomes colorless. Palm
oil is one of the few vegetable oils relatively high in saturated fats, and thus semisolid at room
temperature.36
Palm oil contains almost equal proportions of saturated (palmitic 48%, stearic 4%, and
myristic 1%) and unsaturated acids (oleic 37% and linoleic 10%). The oil can be fractionated to
give palm stearin, palm olein, and palm mid fraction.37 It is used mainly for food purposes but
has some nonfood uses. Valuable byproducts obtained from palm oil are carotene, tocopherols
and tocotrienols (vitamin E), and palmfatty acid distillate (PFAD). Palm kernel oil is lauric
oil, similar in composition to coconut oil (lauric acid 50% and myristic acid 16%) and contains
palmitic acid (8%), capric acid (3%), caprilic acid (3%), stearic acid (2.5%), oleic acid (15%),
and linoleic acid (2.5%).38,39
Palm oil and palm kernel oil are composed of fatty acids, esterifi ed with glycerol just like
any ordinary fat. Both are high in saturated fatty acids, about 50% and 80%, respectively. The
oil palm gives its name to the 16carbon saturated fatty acid, palmitic acid, found in palm oil;
monounsaturated oleic acid is also a constituent of palm oil while palm kernel oil contains mainly
lauric acid.40
Palm oil products are made using milling and refi ning processes, fi rst, using fractionation, then
crystallization and separation processes to obtain a solid stearin and a liquid olein.41 By melting
and degumming, impurities can be removed and then the oil fi ltered and bleached. Next, physical
refi ning removes odors and coloration, to produce refi ned bleached deodorized palm oil (RBDPO),
and free pure fatty acids, used as an important raw material in the manufacture of soaps, washing
powder, and other hygiene and personal care products.42
144 Advances in Food Biochemistry
5.2.1.9 Saffl ower Oil
Saffl ower (Carthamus tinctorius) is a highly branched, herbaceous, thistlelike annual, usually with
many long, sharp spines on the leaves. Saffl ower is grown particularly in India. Traditionally, the
crop was grown for its seeds, used for coloring and fl avoring foods, and making red (carthamin)
and yellow dyes.43
Saffl ower oil is fl avorless and colorless, and is nutritional. It is used mainly as a cooking oil
and for the production of margarine. It may also be taken as a nutritional supplement.44 There
are two types of saffl owers that produce different kinds of oil, one high in monounsaturated fatty
acids (oleic acid) and the other high in polyunsaturated fatty acids (linoleic acid).45 Normally,
it is a linoleicrich oil (about 75% linoleic acid) with LLL (47%), LLO (19%), and LLS (18%) as
the major triacylglycerols. Saffl ower oil rich in oleic acid (about 74%) has also been developed
(Saffola).46
5.2.1.10 Coconut Oil
Coconut oil, also known as coconut butter, is a tropical oil with many applications. It is extracted
from copra, which means dried coconut and is a product of the coconut palm (Cocos nucifera).
Coconut oil (about 3.1 million tonnes per annum) comes mainly from Indonesia and the Philippines.
Coconut oil constitutes seven percent of the total export income of the Philippines, the world’s largest
exporter of the product. Coconut oil was developed as a commercial product by merchants in the
South Seas and South Asia in the 1860s.47
Coconut oil is a fat consisting of about 90% saturated fat. The oil contains predominantly medium
chain triglycerides, with roughly 92% saturated fatty acids, 6% monounsaturated fatty acids, and
2% polyunsaturated fatty acids.48 It is particularly rich in lauric acid (47%), myristic acid (8%), and
caprylic acid (8%), although it contains seven different saturated fatty acids in total. The oil fi nds
extensive use in the food industry and also, usually after conversion to the alcohol (dodecanol), in
the detergent, cosmetic, and pharmaceutical industries. The only other commercially available lauric
oil is palm kernel oil but there also exists lauratecanola and cuphea species.49
Among the most stable of all oils, coconut oil is slow to oxidize, and thus resistant to rancidity,
lasting up to 2 years due to its high saturated fat content. It is best stored in solid form, below
24.5°C in order to extend shelf life.50 However, unlike most oils, coconut oil will not be damaged by
warmer temperatures. Virgin coconut oil is derived from fresh coconuts (rather than dried).51 Most
oils marketed as “virgin” are produced by one of three ways: (1) quick drying of fresh coconut meat
which is then used to press out the oil, (2) wetmilling (coconut milk), with this method the oil is
extracted from fresh coconut meat without drying fi rst. Coconut milk is expressed fi rst by pressing.
The oil is then further separated from the water. The methods which can be used to separate the oil
from the water include boiling, fermentation, refrigeration, enzymes, and mechanical centrifuge52
and (3) wetmilling (direct microexpelling), in this process, the oil is extracted from fresh coconut
meat after the adjustment of the water content, then the pressing of the coconut fl esh results in the
direct extraction of the freefl owing oil.47
5.2.1.11 Cocoa Butter
The cocoa bean (Theobroma cacao) is the source of two important ingredients of chocolate: cocoa
powder and a solid fat called cocoa butter.53 To evaluate the oxidative behavior of cocoa butter, the
autoxidation of refi ned and unrefi ned butter samples is accelerated (oxidized at day light at room
temperature and at 90°C). The quantity of certain aldehydes formed during the oxidation of cocoa
butter is examined by gas chromatography. The oxidation stability of butter is evaluated over a 12
week period.54
The usefulness of cocoa butter for this purpose is related to its fatty acid and triacylglycerol
compositions. The major triacylglycerols are symmetrical disaturated oleic glycerol esters of the
type SOS and include POP (18%–23%), POSt (36%–41%), and StOSt (23%–31%).55,56 Cocoa butter
Lipids, Fats, and Oils 145
commands a good price and cheaper alternatives have been developed. The annual production of
cocoa beans is about 2.7 million tonnes with 45%–48% of cocoa butter.55
5.2.1.12 Sesame Oil
Sesame oil (also known as gingelly oil or til oil) is an organic oil of the plant Sesamum indicum
grown mainly in India and China but also in Myanmar (Burma), Sudan, and Mexico.57 The sesame
seeds are protected by a capsule, which does not burst open until the seeds are completely ripe.
The ripening time tends to vary. For this reason, the farmers cut the plants by hand and place them
together in an upright position to carry out ripening for a few days. The seeds are only shaken out
onto a cloth after all the capsules have opened.58
The annual production is about 0.7 million tonnes. The seed has 40%–60% oil with almost equal
levels of oleic acid (range 35%–54%, average 46%), linoleic acid (range 39%–59%, average 46%),
palmitic acid (7%–12%), palmitoleic acid (trace to 0.5%), stearic acid (3.5%–6%), linolenic acid
(trace to 1%), and eicosenoic acid (trace to 1%). The oil contains sesamin (0.5%–1.1%) and sesamolin
(0.3%–0.6%) and has high oxidative stability due to the presence of natural antioxidants.57
5.2.2 OILS AND FATS OF ANIMAL ORIGIN
Animal fats are rendered tissue fats that can be obtained from a variety of animals. Examples of
edible animal fats are butter, lard (pig fat), tallow, ghee, and fi sh oil. They are obtained from fats in
the milk, meat, and under the skin of the animal.61 Typical fatty acid composition of some animal
fats and oils are summarized in Table 5.5.
5.2.2.1 Butter
Butter, a waterinoil emulsion, comprises of >80% milk fat, but also contains water in the form
of tiny droplets, perhaps some nonmilk fat, with or without salt (sweet butter); texture is a result
of workingkneading during processing at appropriate temperatures, to establish a fat crystalline
network that results in desired smoothness (compare butter with melted and recrystallized butter).62
It is used as a spread, a cooking fat, or a baking ingredient.63
The most common form of butter is made from cows’ milk, but it can also be made from the milk
of other mammals, including sheep, goats, buffalo, and yaks. Salt, fl avorings, or preservatives are
sometimes added to butter. When refrigerated, butter remains a solid, but softens to a spreadable
consistency at room temperature, and melts to a thin liquid consistency at 32°C–35°C. Butter generally
has a pale yellow color, but varies from deep yellow to nearly white.64
TABLE 5.5
Typical Fatty Acid Composition of the Main Animal Oils and Fats
Kind of
Animal
Oils
and Fats
Fatty Acids
Saturated
(g100 g)
Monounsatu rated
(g100 g)
Polyunsatu rated
(g100 g)
14:0
(wt%)
16:0
(wt%)
18:0
(wt%)
18:1
(wt%)
18:2
(wt%)
Butter 54 19.8 2.6 12 26 11 28 2
Lard 40.8 43.8 9.6 2 26 11 44 11
Tallow 50 42 4 26 26 14 47 3
Fish oil 26 25 35 9 17 10 10 22
Sources: Gunstone, F.D., The Chemistry of Oils and Fats—Sources, Composition, Properties and Uses, CRC Press, Boca
Raton, FL, p. 7, 2004; Wikipedia, Fat, 2007, Available at: http:en.wikipedia.orgwikiFat (accessed 2022008).
146 Advances in Food Biochemistry
Production of butter is about 5.8 million tonnes a year on a fat basis. As a waterinoil emulsion it
contains 80%–82% milk fat and 18%–20% of an aqueous phase. It is produced throughout the world
(6–7 million tonnes a year). Butterfat is very complicated in its fatty acid and triacylglycerol composition.
In addition to the usual C16 and C18 acids, it contains shortchain and mediumchain acids
(C4–C14), a range of trans monoene acids, mainly 18:1, and oxygenated and branchedchain acids.
The trans acids represent 4%–8% of the total acids.65 Butter contains some cholesterol (0.2%–0.4%).
Spreads with lower levels of fat are also available. Butter that spreads directly from the refrigerator
is made by removing some of its higher melting glycerol esters or by blending with a vegetable oil.66
The fl ow diagram of butter manufacture is shown in Figure 5.2.
5.2.2.2 Lard
Lard refers to pig fat in both its rendered and unrendered forms. Lard was commonly used as a
cooking fat or shortening, or as a spread similar to butter. Its use in contemporary cuisine has
diminished because of health concerns posed by its saturated fat content and its often negative
image. The culinary qualities of lard vary somewhat depending on the part of the pig from which
the fat is taken and how the lard is processed.67
Lard can be obtained from any part of the pig as long as there is a high concentration of fatty
tissue. The highest grade of lard, known as leaf lard, is obtained from the “fl are” fat deposit surrounding
the kidneys and inside the loin. The next highest grade of lard is obtained from fatback,
the hard fat between the back skin and fl esh of the pig.68 The lowest grade (for purposes of rendering
into lard) is obtained from the soft caul fat surrounding digestive organs, such as small intestines,
though caul fat is often used directly as a wrapping for roasting lean meats or in the manufacture
of pates.69
Industrially produced lard is rendered from a mixture of high and low quality fat sources from
throughout the pig. It is typically hydrogenated, and often treated with bleaching and deodorizing
agents, emulsifi ers, and antioxidants.68 Such treatments make the lard shelf stable.70 The available
quantities of lard are about 6 million tonnes a year. The fat contains palmitic (20%–32%),
stearic (5%–24%), oleic (35%–62%), and linoleic (3%–16%) acids as major components. It is
unusual in that 70% of the palmitic acid is in the sn2 position. It also contains cholesterol
(0.37%–0.42%).34
5.2.2.3 Tallow
Animal edible tallow is normally obtained from beef but also from sheep and goats, processed from
suet. Unlike suet, tallow can be stored for extended periods without the need for refrigeration to
prevent decomposition, provided it is kept in an airtight container to prevent oxidation. It is used in
animal feed, to make soap, for cooking, as bird feed, and was used for making candles. It can be
used as a raw material for the production of biodiesel and other oleochemicals.71
The annual production of tallow is about 7 million tonnes. Tallow contains mainly saturated
acids (50%): palmitic acid (26%), stearic acid (14%), and myristic acid (3%). It also contains monounsaturated
acids (42%), especially oleic acid (47%) and palmitoleic acid (3%), and polyunsaturated
acids (4%), especially linoleic acid (3%) and linolenic acid (1%).72 Also present are oddchain,
branchedchain, and trans fatty acids, and cholesterol (0.08%–0.14% in beef tallow and 0.23%–
0.31% in mutton tallow).73
5.2.2.4 Ghee
Ghee is a solid fatbased product made in India from cow or buffaloripened milk. It is less perishable
than butter and, therefore, more suitable for a tropical climate.74 Milk is curdled. The curd
is then manually churned until it precipitates butter and leaves behind some whey. The butter
is then heated on a low fl ame until a layer of white froth covers the surface. This state indicates
the end of the process, and the liquid obtained on fi ltering the suspension is pure ghee.75 Ghee
is made by simmering unsalted butter in a large pot until all water has boiled off and protein
Lipids, Fats, and Oils 147
has settled to the bottom. The cooked and clarifi ed butter is then spooned off to avoid disturbing
the milk solids on the bottom of the pan. Unlike butter, ghee can be stored for extended periods
without refrigeration, provided it is kept in an airtight container to prevent oxidation and remains
moisturefree.74
5.2.2.5 Fish Oil
Fish oil is the lipid extracted from the body, muscle, liver, or other organ of fi sh. The major
producing countries are Japan, Chile, Peru, Denmark, and Norway and the main fi sh sources
Raw milk
storage
Skim
Pasteurization
Storage
Evaporation
Drying
Buttermilk
Storage
Pasteurisation
Evaporation
Drying
Distribution
Storage
Packaging
Salting
Working
Butter
Separation
Crystallizing
Churning
Aging
Cream ripening
Starter culture
inoculation
Pasteurization
Storage
Separation Cream
Raw
cream
delivery
FIGURE 5.2 Flow diagram of butter manufacture.
148 Advances in Food Biochemistry
are herring (Clupea harengus), menhaden (Brevoortia tyrannus), capelin (Mallotus villosus),
anchovy (Engraulis encrasicolus), sardine (Sardina pilchardus), tuna (Opuntia tuna), and cod
(Gadus morhua liver).76
Fish oil is recommended for a healthy diet because it contains the ω3 fatty acids eicosapentaenoic
acid (EPA) and docosahexaenoic acid (DHA), precursors to eicosanoids that reduce infl ammation
throughout the body.77 However, fi sh do not actually produce ω3 fatty acids, but instead
accumulate them from either consuming microalgae that produce these fatty acids, as is the case
with prey fi sh like herring and sardines, or, as is the case with fatty predatory fi sh, by eating prey
fi sh that have accumulated ω3 fatty acids from microalgae. Such fatty predatory fi sh like mackerel,
lake trout, albacore tuna, and salmon may be high in ω3 fatty acids, but due to their position at the
top of the food chain, these species can accumulate toxic substances (mercury, dioxin, PCBs, and
chlorates).78
Fish oils contain a wide range of fatty acids from C14 to C26 in chain length with 0–6 double
bonds. The major acids include saturated (14:0, 16:0, and 18:0), monounsaturated (16:1, 18:1, 20:1,
and 22:1) and n–3 polyene members (18:4, 20:5, 22:5, and 22:6). Fish oils are easily oxidized and are
commonly used in fat spreads only after partial hydrogenation.79 However, they are the most readily
available sources of n–3 polyene acids, especially, EPA and DHA, and with appropriate refi ning
procedures and antioxidant addition these acids can be conserved and made available for use in
food. The longchain polyene acids are valuable dietary materials and there is a growing demand
for high quality oil rich in EPA and DHA.80
In 2005, fi sh oil production declined in all the main producing countries with the exception of
Iceland. The production estimate was about 570,000 tonnes in the fi ve main exporting countries
(Peru, Denmark, Chile, Iceland, and Norway) in 2005, a 12% decline from the 650,000 tonnes produced
in 2004. Peru continues to be the main fi sh oil producer in the world, with about one fourth
of the total fi sh oil production. Though Peruvian catches of fi sh were destined for reduction in 2005
it was more or less in line with the 2004 result, however, fi sh oil production declined from 350,000
tonnes to 290,000 tonnes, due to the lower fat content of the fi sh. In the recent summer months, the
fat content was as low as 2% as compared to 4% in 2004.81
5.3 PHYSICAL PARAMETERS
5.3.1 CRYSTALLIZATION, MELTING POINT, AND POLYMORPHISM
Longchain compounds frequently exist in more than one crystalline form. This property of polymorphism
is of both scientifi c and technical interest and consequently these compounds have more
than one melting point.82
5.3.1.1 Crystallization
Crystallization, is a nonchemical process used by the vegetable oil industry to obtain triacylglycerides
(TAGS) fractions with the given phase change properties. Overall, four different events are
involved during crystallization, namely supercooling, nucleation, crystal growth, and crystal ripening.
Blends of palm stearin in sesame oil were used as a model system. The results showed that the
involvement of molecular localorder and sporadic nucleation, depend on the cooling rate used and
the extent of supercooling during vegetable oil crystallization. Additionally, during crystal growth
the involvement of secondary crystallization is defi nite.83
A crystal nucleus is the smallest crystal that can exist in a solution and is dependent on the
concentration and temperature. Spontaneous nucleation rarely occurs in fats. Instead heterogeneous
nucleation occurs on solid particles or on the walls of the container. Once the crystals
are formed, fragments that dropoff may either redissolve or act as nuclei for further crystal
formation.84
Lipids, Fats, and Oils 149
5.3.1.2 Melting Point
The melting point of a crystalline solid is the temperature range at which it changes its state from
solid to liquid. Although the phrase would suggest a specifi c temperature, most crystalline compounds
actually melt over a range of a few degrees or less. At the melting point, the solid and liquid
phases exist in equilibrium at a total pressure of 1 atm.85 The melting points of the acids with an
even number of carbon atoms in the molecule and their methyl esters plotted against a chainlength
fall on the smooth curves lying above similar curves for the odd acids and their methyl esters. Odd
acids melt lower than even acids with one less carbon atom. The two curves for saturated acids
converge at 120°C–125°C.86
To reduce the melting point of a tallowrapeseed oil mixture, the triglyceride composition of the
mixture was altered by enzymatic interesterifi cation in a solventfree system. The interesterifi cation
and hydrolysis were followed by melting point profi les and by free fatty acid determinations. The
degree of hydrolysis was linearly related to the initial water content of the reaction mixture. The
rate of the interesterifi cation reaction was infl uenced by the amount of enzyme but not much by
temperature, between 50°C and 70°C. The melting point reduction achieved by interesterifi cation
depended on the mass fractions of the substrates: the lower the mass fraction of tallow, the larger
the reduction of the melting point.87
5.3.1.3 Polymorphism
Polymorphism is the phenomenon where a compound can precipitate to form numerous crystal
structures. The different crystalline structures each have different physical properties, which can
change the use of the chemical. The physical properties that may differ from one polymorphism
to another include: solubility, density, melting point, and even color. One of the variables that
affect the crystallization process is the solvent that is used in the precipitation. The solvent may
cause less stable polymorphisms to form instead of those that are more stable.88 Each polymorphic
form, sometimes termed polymorphic modifi cation, is characterized by specifi c properties, such
as xray spacings, specifi c volume, and melting point.89 Transformation of one polymorphic form
into another can take place in the solid state without melting. Two crystalline forms are said to be
“monotropic” if one is stable and the other metastable throughout their existence and regardless
of the temperature change. The temperature, at which the relative stability changes, is known as
the transition point.90
The polymorphism of rapeseed oils with high and low erucic acid content was investigated using
differential scanning calorimetry and xray diffraction. Both oils were hydrogenated to various
iodine values. The fatty acid pattern showed that erucic acid is slowly saturated. The melting curves
were followed by DSC and Pulsed NMR. For low iodine value the low erucic acid rapeseed oil
exhibits a second melting peak owing to the appearance of new triglycerides with different properties.
Samples of hydrogenated rapeseed oils were aged at 20°C and 29°C.91
5.3.2 DENSITY, VISCOSITY, AND REFRACTIVE INDEX
5.3.2.1 Density
Density is defi ned as mass per unit volume, i.e., metric ton per barrel. The oil industry in different
parts of the world uses different units of measurements. For example, in Europe, the metric ton (a
mass unit) is generally accepted as the unit of measurement.92 Density may not seem an exciting
physical property to many technologists, but it is very important in the trading of oils since shipments
are sold on a weight basis but measured on a volume basis. These two values are related
by density, so it is important to have correct and agreed values for this unit. Density is not the
same for all oils as it depends on the fatty acid composition and minor components, as well as the
temperature.93
150 Advances in Food Biochemistry
5.3.2.2 Viscosity
The combination of molecular size and autocohesive character produces a property in all fl uids
known as “viscosity.” It can be defi ned either as a resistance to fl ow or as a resistance to the
movement of something through that fl uid. Both of these defi nitions represent the resistance
of the molecules of the fl uid to separate from each other or “sheer.”94 Viscosity is temperature
dependant. By heating the olive oil, it becomes more and more waterlike in its consistency.
Alternatively, viscosity increases as temperature decreases, and oils become more solidlike in
character.95
The viscosity of a vegetable oil depends on its chemical composition (iodine value and saponifi
cation value) and the temperature of measurement. Equations have been derived which permit the
calculation of viscosity from the knowledge of the other three parameters.96
5.3.2.3 Refractive Index
Refractive index is the ratio of the velocity of light (of specifi c wavelength) in air to the velocity in
the substance of interest. Refractive index may also be defi ned as the sine of the angle of incidence
divided by the sine of the angle of refraction, as light passes from air into the substance. Refractive
index is a fundamental property used in conjunction with other properties to characterize hydrocarbons
and their mixtures.97
5.4 CHEMICAL PARAMETERS
5.4.1 OXIDATION
Oxidation of unsaturated fatty acids is the main reaction responsible for the degradation of lipids.
Indeed, the oxidation level of oil and fat is an important quality criterion for the food industry.
Oxidation of oils not only produces rancid fl avors but can also decrease the nutritional quality
and safety by the formation of oxidation products, which may play a role in the development of
diseases.98
Many methods have been developed to access the extent of oxidative deterioration, which
are related to the measurement of the concentration of primary or secondary oxidation products
or of both. The most commonly used are peroxide value (PV) that measures volumetrically the
concentration of hydroperoxides, anisidine value (AV), spectrophotometric measurement in the
UV region and gas chromatographic (GC) analysis for volatile compounds.99 Vibrational spectroscopy,
because of its high content in molecular structure information, has also been considered
to be useful for the fast measurement of lipid oxidation. In contrast to the time consuming
chromatographic methods, modern techniques of IR and Raman spectrometry are rapid and do
not require any sample preparation steps prior to analysis. These techniques have been used to
monitor oil oxidation under moderate and accelerated conditions and the major band changes have
been interpreted.100
Raman spectroscopy is poorly explored in its application to edible oils. It has been basically
applied to the characterization and authentication, and to the quantitative analysis of total unsaturation,
cistrans isomers, and free fatty acid content.101,102
5.4.1.1 Autoxidation
Autoxidation is the process in foods and bulk lipids, which leads to rancidity. Rancidity is the
spoiled offfl avor obtained by subjective organoleptic appraisal of food.103 Autoxidation is the oxidative
deterioration of unsaturated fatty acids via an autocatalytic process consisting of a free
radical mechanism. This indicates that the intermediates are radicals (odd electron species) and
that the reaction involves an initiation step and a propagation sequence, which continues until the
operation of one or more termination steps. Autoxidation of lipid molecules is briefl y described by
reactions 1–3.104
Lipids, Fats, and Oils 151
1. Initiation RH ⇒ R• + H•
or X• + RH ⇒ R• + XH
2. Propagation R• + O2 ⇒ ROO•
ROO• + RH ⇒ ROOH + R•
3. Termination R• + R• ⇒ R–R
R• + ROO• ⇒ ROOR
ROO• + ROO• ⇒ ROOR + O2
In the initiation step, hydrogen is abstracted from an olefi nic acid molecule (RH) to form alkyl
radicals (R•), usually in the presence of a catalyst, such as metal ions, light, heat, or irradiation, at a
relatively slow rate. The duration of the initiation stage varies for different lipids and depends on the
degree of unsaturation and on the presence of natural antioxidants.105
In the propagation sequence, given an adequate supply of oxygen, the reaction between alkyl
radicals and molecular oxygen is very fast and peroxyl radicals are formed (ROO•). These react
with another fatty acid molecule producing hydroperoxides (ROOH) and new free radicals that
contribute to the chain by reacting with another oxygen molecule. Hydroperoxide molecules can
decompose in the presence of metals to produce alkoxyl radicals (RO•), which cleave into a complex
mixture of aldehydes and other products, i.e., secondary oxidation products.106 The mutual annihilation
of free radicals is known as the termination stage, when the free radicals R• and ROO• interact
to form stable, nonradical products. The rate of oxidation of fatty acids increases with their degree
of unsaturation. The relative rate of autoxidation of oleate, linoleate, and linolenate is in the order of
1:40 to 50:100 on the basis of oxygen uptake and 1:12:25 on the basis of peroxide formation.107
5.4.1.2 AzoInitiated Oxidation
An intrinsic problem in the determination of rate constants in lipid oxidation is the uncertainty
about the rate of initiation Ri, according to the reaction:
RH + X• ⇒R• + XH
One possible way of overcoming this problem is to introduce into the reaction mixture a compound
that decomposes at a constant rate to free radicals (X•) capable of extracting a hydrogen atom from
the PUFAs (RH) and consequently initiating the autoxidation process. The compounds most frequently
used for this are the socalled azoinitiators (X–N=N=X), which thermally decompose to
highly reactive carboncentered radicals.108
Therefore, azoinitiators are useful for in vitro studies of lipid peroxidation generating free radicals
according to the following reaction:
− = − ⇒ • + X N N X 2X N2
The watersoluble azoinitiator AAPH2,2Azobis(2amidinopropane)dihydrochloride can be used
to produce radicals in the aqueous phase, whereas the lipidsoluble AMVN 2,2′azobis(2,4
dimethylvaleronitrile) can be used to produce radicals in the lipid phase.109 AAPH decomposes
with a fi rstorder rate constant of Kd = 6.6 × 10−5min at 37°C, and the fl ux of the free radicals is
proportional to the AAPH concentration.110
5.4.1.3 Photosensitized Oxidation
Photooxidation involves the direct reaction of lightactivated, singlet oxygen (1O2) with unsaturated
fatty acids and the subsequent formation of hydroperoxides. In the most stable triplet state (two
unpaired electrons in a magnetic fi eld), oxygen is not very reactive with unsaturated compounds.
Photosensitized oxidation involves reaction between a double bond and highly reactive singlet
152 Advances in Food Biochemistry
oxygen (paired electrons and no magnetic moment) produced from an ordinary triplet oxygen by
light in the presence of a sensitizer, such as chlorophyll, erythrosine, or methylene blue.111
1 1 3 3
1. sens + hν⇒ sens ⇒ sens + O2
3 3 1 1
2. sens + O2 ⇒ sens + O2
The singlet oxygen oxidation differs from autoxidation in several important respects: (1) it is an ene
and not a radical chain reaction, (2) it gives products which are similar in type but not identical in
structure to those obtained by autoxidation, and (3) it is a quicker reaction and its rate is related to
the number of double bonds rather than the number of doubly activated allylic groups.105
5.4.1.4 Metal Catalyzed Oxidation
Many natural oils contain metals such as cobalt iron, magnesium, and copper, which possess two
or more valence states with a suitable oxidation–reduction potential and can serve as excellent prooxidants
in lipid oxidation reactions.112 Contamination of oils with specifi c metals (copper, iron,
etc.) can also occur during the refi ning procedure.
Metals can initiate fatty acid oxidation by a reaction with oxygen. The anion thus produced can
either lose an electron to give a singlet oxygen or react with a proton to form a peroxyl radical, which
is a good chain initiator.113
+ + ⇒ + + + −
1
( 1) 2
2 2
O
M O M O
OH
n n i
i

Many oxygenated complexes of transition metals have now been isolated and used as catalysts for
the oxidation of olefi ns and recent evidence supports the initiation of autoxidation through the formation
of a metal hydroperoxide catalyst complex.
Once a small amount of hydroperoxides is formed, the transition metals can promote the decomposition
of the preformed hydroperoxides due to their unpaired electrons in the 3d and 4d orbitals.
A metal, capable of existing in two valence states typically acts as:
Mn+ + ROOH⇒ROi + OH− +M(n+1)+—the reduced metal ion is oxidized
M(n+1)+ + ROOH⇒ROOi + H+ +Mn+—the oxidized metal is reduced
⇒ + +
2ROOH RO ROO H2O—net reaction i
In a system containing multivalent metal ions, such as Cu+ and Cu2+ or Fe2+ and Fe3+, the hydroperoxides
decompose readily with the formation of both RO• and ROO• as the metal ions undergo
oxidation–reduction.114
5.4.1.5 Enzyme Catalyzed Oxidation
The basic chemistry of enzyme catalyzed oxidation of food lipids such as in cereal products, or in
many fruits, and vegetables is the same as for autoxidation, but the enzyme lipoxygenase (LPX)
is very specifi c for the substrate and for the method of oxidation.115 Lipoxygenases are globulins
with molecular weights ranging from 0.6–1 × 105 Da, containing one iron atom per molecule at the
active site.
Lipids, Fats, and Oils 153
LPX type 1, from many natural sources e.g. potato, tomato, and soybean, prefers polyunsaturated
fatty acids that have as their best substrate linoleic acid, which is oxidized to 9 and 13 hydroperoxides.
These hydroperoxides suffer fragmentation to give shortchain compounds (hexanal,
9oxononanoic acid, 2nonenal), some of which have marked and characteristic odors. LPX type
2 (present in gooseberry, soybean, and legumes), catalyzes the oxidation of acylglycerols, whereas
cooxidation of other plant components e.g., carotenoids may also occur.116 In that case hydroperoxides
may suffer enzymecatalyzed reactions to give a mixture of products as shown in the following
scheme:
Enzymatic
Lipoxygenase reactions
RH + O2 ⎯⎯⎯⎯⎯→ROOH⎯⎯⎯⎯→ROH, RCHO, ROOR, RCO2H
5.4.1.6 Decomposition of Hydroperoxides
A large body of scientifi c evidence suggests that the loss of food palatability as a result of lipid oxidation
is due to the production of short chain compounds from the decomposition of the hydroperoxides.
The volatile compounds produced from the oxidation of edible oils are infl uenced by the
composition of the hydroperoxides and the positions of oxidative cleavage of double bonds in the
fatty acids.117
A variety of compounds such as hydrocarbons, alcohols, furans, aldehydes, ketones, and acid
compounds are formed as secondary oxidation products and are responsible for the undesirable fl avors
and odors associated with rancid fat.118 The offfl avor properties
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ADVANCES IN CALCULATION OF MINIMUM MISCIBILITY PRESSURE

ADVANCES IN CALCULATION OF MINIMUM MISCIBILITY PRESSURE

I would like to express my deepest gratitude to my supervisor, Professor Russell T. Johns, who contributed immensely to my education and research throughout my studies at UT Austin. It was my privilege to be his student and to complete my studies under his supervision.
I would like to thank my research committee, Drs. Bryant, DiCarlo, Dindoruk, and
Sepehrnoori, who have further enriched this dissertation with their suggestions and comments. I am also grateful for the feedback I received from Kristian Mogensen at Maersk regarding PennPVT calculations. His feedback led to new perspectives related to the subject of this dissertation and formed the basis of Chapter 4. The funding of this research was provided by Gas Flooding JIP. I sincerely thank Gas Flooding JIP and its industry affiliates for their financial support, and for investing on fundamental research in the field of Petroleum Engineering
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Characterization of three phase flow and WAG Injection in Oil Reservoirs

CHARACTERIZATION OF THREE PHASE FLOW AND WAG INJECTION IN OIL RESERVOIRS

Large quantities of oil usually remain in oil reservoirs after conventional water floods. A significant part of this remaining oil can still be economically recovered by Water AlternatingGas (WAG) injection. WAG injection involves drainage and imbibition processes taking place sequentially, hence the numerical simulation of the WAG process requires reliable knowledge of threephase relative permeability (kr) accounting for cyclic hysteresis effects.
In this study, the results of a series of unsteadystate twophase displacements and WAG coreflood experiments were employed to investigate the behaviour of threephase and hysteresis effects in the WAG process. The experiments were carried out on two different cores with different characteristics and wettability conditions, using a low IFT (interfacial tension) gas–oil system.
The first part of this study, evaluates the current approach used in the oil industry for simulation of the WAG process, in which the twophase relative permeability data are employed to generate threephase kr values using correlations (e.g. Stone, Baker). The performance of each of the existing threephase relative permeability models was assessed against the experimental data. The results showed that choosing inappropriate threephase kr model in simulation of the WAG experiments can lead to large errors in prediction of fluid production and differential pressure. While some models perform better than others, all of the threephase kr models examined in this study failed to adequately predict the fluid production behaviour observed in the experiments. The continued production of oil after the breakthrough of the gas, which was one of the
features of gas and WAG injection experiments at low gasoil IFT, was not captured with these models.
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The chemical components of detergents and their roles in the washing process

THE CHEMICAL COMPONENTS OF DETERGENTS AND THEIR ROLES IN THE WASHING PROCESS

Laundry detergents are formulated from six groups of substances :
. surfactants
. builders
. bleachingagents
. enzymes
. fillers
. other minor additive
Surfactants
Are organic chemicals, obtained through complex chemical reactions, from oil or
fat raw materials. They have wetting, emulsifying and dispersing properties,
enabling the removal of dirt (soil) from fabrics and keeping the soil
suspended in the washing water.

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Học tiếng anh qua báo Bản tin đầu tư hôm nay số 2

HỌC TIẾNG ANH QUA BÁO BẢN TIN ĐẦU TƯ HÔM NAY SỐ 2

00:00 The U.S. Energy Information Administration = Văn phòng Thông tin Năng lượng Mỹ
00:02 pushed its forecast for oil production next year = đẩy mức dự báo về sản xuất dầu năm tới
00:05 by two hundred and fifty thousand barrels per day = lên thêm 250 ngàn thùng một ngày
00:07 as a result of the boom in shale oil drilling. = là kết quả của sự bùng nổ trong việc khoan dầu phiến
00:10 The U.S. agency now expects domestic output = Cơ quan Mỹ giờ đây kỳ vọng sản lượng nội địa
00:13 to reach almost ten million barrels per day, = sẽ đạt 10 triệu thùng một ngày
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ĐỀ KIỂM TRA TIẾNG ANH HỌC KỲ II LỚP 9 NĂM HỌC 2011 2012

ĐỀ KIỂM TRA TIẾNG ANH HỌC KỲ II LỚP 9 NĂM HỌC 2011 2012

1. He is a _________________ driverWELL2. A huge _______________ wave struck Anchorage, Alaska in the TIDE1960s.3. The accident happened because he drove ________________.CARE4. There are many ___________________ in our country of a year.CELEBRATEV. Read the passage carefully then answer the questions. (2 pts)Many people still believe that natural resources will never be used up. Actually, the world’senergy resources are limited. Nobody knows exactly how much fuel is left. However, we shoulduse energy resources economically and try to find out alternative sources of power. According toProfessor Marvin Burnham of the New England Institute of Technology, we have to startconserving coal, oil and gas before it is too late: and nuclear power is the only alternative.However, many people do not approve of using nuclear power because it is very dangerous.What would happen if there were a serious nuclear accident? Radioactivity causes cancerand may badly affect the future generations. The most important thing is that we should usenatural resources as economically as possible.1. What do many people still think about natural resources?_________________________________________________________________________2. Do we know exactly how much fuel is left?_________________________________________________________________________3. According to Professor Marvin Burnham, what do we have to do?_________________________________________________________________________4. How should we use natural resources?_________________________________________________________________________VI.Rewrite the sentences so that it means the same as the first one, beginning with the givenwords. (2 pts)
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agriculture marketing

AGRICULTURE MARKETING

marketing trong nông nghiệp
slide lý thuyết bài giảng
First, You may be preparing for a career in food marketing, and your success will depend on the knowledge of the field.
Second, you may plan to be a food producer who will need to understand the changing nature of the marketing system which will influence your sales, price and income.
Third, you will most certainly be a food consumer whose food supply and prices will depend upon the food production and marketing system.
Finally, you will be a citizen with responsibilities to shape and regulate the food industry in ways that serve the public interest.
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GMAT VOCABULARY FLASH CARDS91

GMAT VOCABULARY FLASH CARDS91

GMAT Vocabulary Flash Cards @ englishpdf.com andenglishteststore.com File 091bungler(n) a clumsy person--------------------buoyancy(n) Power or tendency to float on or ina liquid or gas.--------------------buoyant(adj) Having the power or tendency tofloat or keep afloat.--------------------bureau(n) A chest of drawers for clothing, etc.

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How green the Jatropha curcas Biodiesel remains when contaminated with Kerosene?

HOW GREEN THE JATROPHA CURCAS BIODIESEL REMAINS WHEN CONTAMINATED WITH KEROSENE?

Biodiesel, an environment friendly and renewable fuel, has emerged as an alternate to conventional diesel
fuel. Out of various nonedible oils, Jatropha curcas oil (JCO) as a feedstock for biodiesel, has been gaining
the attention of various researchers all over the world. However, growing demand for biodiesel has given birth
to mal practices like adulteration to lower its cost and degrade the quality. The present study is carried out to
purify and characterize Jatropha curcas biodiesel (JCB) produced from JCO by transesterification process.
The JCB was purified by different methods and characterized for its purity. Its adulteration with kerosene oil
has been studied using Gas chromatography,
1
HNMR spectroscopy (Proton Nuclear Magnetic Resonance),
viscosity, density and TGA (ThermoGravimetric Analysis). A number of calibration curves and correlations
are developed that can be used to find out the extent of adulteration in biodiesel and eventually to know its
impact on engine life and associated emissions.
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ENZYMIC BROWNING IN POTATOES

ENZYMIC BROWNING IN POTATOES

* E-mail: buschj@lincoln.ac.nz.Biochemical Education 27 (1999) 171}173Enzymic browning in potatoes: a simple assay for a polyphenoloxidase catalysed reactionJ.M. Busch*Animal and Food Sciences Division, Lincoln University, P.O. Box 84, Canterbury, New ZealandAbstractA simple laboratory procedure is described for demonstrating the enzyme-catalysed reaction in the browning of potato. It requiresa minimum of equipment and can be completed in a 3-h lab class.  1999 IUBMB. Published by Elsevier Science Ltd. All rightsreserved.1. IntroductionThis paper describes a student laboratory proceduredesigned to show the enzyme-catalysed reaction resultingin the browning of raw potato. Although several methodsare available for recording enzymic browning in plants,they generally require the use of toxic chemicals (phenol)or expensive equipment (eg. spectrophotometers andoxygen electrodes) [1,2]. This method allows students todemonstrate enzymic browning in a semi-quantitativeway using non-toxic chemicals. It can be completed ina 3-h laboratory class.For two years the basic experiment plus the problemsolving exercises have been used as the basis on whichfood biochemistry students in our institution develop anexperimental design to show the extent of enzymicbrowning in a particular potato cultivar. They have alsodeveloped feasible procedures that could be used by foodindustries to prevent enzymic browning. These studentshave reported favourably on this application of a simplepractical experiment to problem solving in real-life situ-ations in the food industry [3].
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TRUNG QUỐC GSCMN1CHN1S3

TRUNG QUỐC GSCMN1CHN1S3

made by or on behalf of the domestic industry, the contents of the application and the evidenceattached thereto, and shall decide whether or not to initiate an investigation. In special circumstances,the examination period may be extended.Prior to the decision to initiate an investigation, the government of the country (region) theproduct of which may be subject to such investigation shall be invited for consultation regarding thesubsidy in question.Article 17 An application shall be considered to have been made by or on behalf of thedomestic industry and a countervailing investigation may be initiated, if the application is supportedby those domestic producers whose collective output constitutes more than 50 per cent of the totalproduction of the like product produced by that portion of the domestic industry expressing eithersupport for or opposition to the application. However, no investigation shall be initiated when theoutput of those domestic producers expressly supporting the application accounts for less than25 per cent of total production of the like domestic product.Article 18 If, in special circumstances, the Ministry of Commerce decides to initiate aninvestigation without having received any written application for a countervailing investigation, itshall proceed only if it has sufficient evidence of the existence of a subsidy, injury and causal link tojustify the initiation of an investigation.Article 19 The Ministry of Commerce shall publish the decision to initiate an investigationand notify the applicant, the known exporters, importers and other interested organizations andindividuals (hereinafter collectively referred to as “the interested parties”), and the government of theexporting country (region).As soon as the decision to initiate an investigation is published, the Ministry of Commerceshall provide the full text of the written application to the known exporters and the government of theexporting country (region).G/SCM/N/1/CHN/1/Suppl.3Page 6Article 20 The Ministry of Commerce may conduct investigation and collect informationfrom the interested parties by, among others, sending questionnaires, using samples, holding public
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Tên các tổ chức và chức vụ nhà nước trong tiếng anh

TÊN CÁC TỔ CHỨC VÀ CHỨC VỤ NHÀ NƯỚC TRONG TIẾNG ANH

... Meteorology Tổng Cục Thể dục thể thao : General Department of Sports and Physical Training Tổng Cục Thống kê : General Department of Statistics 27 2) Các Bộ quyền Mỹ stt 10 11 12 13 14 Tên Tiếng Anh. .. ban tiếp nhận viện trợ nước : Committee for The reception of Foreign Aid Tổng Cục Bưu điện :General Post office Tổng Cục dạy nghề : General Department of Job training Tổng Cục dầu khí :General... Oil and General Gas Tổng Cục Du lịch : General Department of Tourism Tổng Cục Địa chất : General Department of Geology Tổng Cục Đường sắt : General Department Of Railways Tổng Cục Khí tượng thủy
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TOEFL IBT VOCABULARY FLASH CARDS189

TOEFL IBT VOCABULARY FLASH CARDS189

English Vocabulary Flash Cards @ englishpdf.com andenglishteststore.com File 189efficacious(adj) Effective.--------------------efficacy(n) The power to produce an intendedeffect as shown in the production of it.--------------------efficiency(n) The state of possessing adequateskill or knowledge for the performanceof a duty.--------------------efficient

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Legislative trends, advances in testing predictive tools

LEGISLATIVE TRENDS, ADVANCES IN TESTING PREDICTIVE TOOLS

Outline
• Evolution of Chemicals Legislation
– Addressing much larger numbers of substances in
Canada, Europe, U.S.
• Predictive Tools
– Physiologically Based Pharmacokinetic (PBPK) Modelling
– Hazard
• Combined Exposure to Multiple Chemicals
• The Need for More Efficient Testing Strategies
• ReadingInformation Sources
Evolving Legislative Mandates for
Industrial Chemicals
• Most chemicals already in use at the time of introduction
of modern chemicals legislation in Europe and North
America (late 1980’s) were “grandfathered”
– No testing, assessment were required
• New chemicals required assessment
• Between the late 1980s and late 1990s, countries
focussed assessments on approx. 100 out of the tens to
hundreds of thousands of industrial chemicals in use
(i.e., 0.1% to 1%)
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Basic offshore UK safety 2008

BASIC OFFSHORE UK SAFETY 2008

Basic offshore UK safety 2008 is the basic safety guild for the new employee, who going to work in offshore oil gas industry
All rights from this course handout are registered. No part of this publication may be produced, stored in a retrieval system or transmitted in any form or by any means, including electronic, mechanical, by photo copy, through recording or otherwise, without prior written permission from Falck Nutec BV.
Alle rechten van dit cursus handboek zijn geregistreerd. Niets uit deze publicatie mag gereproduceerd of opgeslagen worden. Ook niet in welke digitale vorm verstuurd of gekopieerd worden. Dit mag alleen met schriftelijke toestemming van Falck Nutec B.V.
© Copyright 2008 Falck Nutec Netherlands B.V. ISBN 9080478814 Revision 005 NL (2008) Research and Development
Basic
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BS 5440 2 2000 installation and maintenance of flues and ventilation for gas appliances of rated

BS 5440 2 2000 INSTALLATION AND MAINTENANCE OF FLUES AND VENTILATION FOR GAS APPLIANCES OF RATED

BS 544022000 Installation and maintenance of flues and ventilation for gas appliances of rated .pdfBS 544022000 Installation and maintenance of flues and ventilation for gas appliances of rated .pdfBS 544022000 Installation and maintenance of flues and ventilation for gas appliances of rated .pdfBS 544022000 Installation and maintenance of flues and ventilation for gas appliances of rated .pdfBS 544022000 Installation and maintenance of flues and ventilation for gas appliances of rated .pdfBS 544022000 Installation and maintenance of flues and ventilation for gas appliances of rated .pdf

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Homework advanced course of glycobiology and glycotechnology phamkhanh dung d1

HOMEWORK ADVANCED COURSE OF GLYCOBIOLOGY AND GLYCOTECHNOLOGY PHAMKHANH DUNG D1

Nowadays, the oily industry in Japan has problems, the degree of selfsufficiency in edible oil is only 3% and most of them is imported from abroad. Beside, biodiesel industry has become important due to the shortage of the fossil oil and increasing awareness of environmental issue. However, use of sustainable biomass for biodiesel production is undoubtedly a globally attractive field of biofuels study as the interest in alternative energy source increase.

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GAS ASSISTED GRAVITY DRAINAGE (GAGD) PROCESS FOR IMPROVED OIL RECOVERY

GAS ASSISTED GRAVITY DRAINAGE (GAGD) PROCESS FOR IMPROVED OIL RECOVERY

ABSTRACTWater Alternating Gas injection (WAG) or Simultaneous Water and Gas Injection (SWAG) floods have been proposed as very good solution to overcome gravity segregation and better EOR performance in compare to conventional continuous gas injection (CGI). However WAGBased processes cause some problems associated with increased water saturation including diminished gas injectivity. As an effective alternative for WAG, Gas Assisted Gravity Drainage (GAGD) for conventional reservoirs has been developed (US Patent 20060289157) that takes advantage of the natural segregation of gas from liquid hydrocarbon during injection. The GAGD process consists of placing a horizontal producer near the bottom of oil column and injecting gas through existing vertical wells. As the injected gas rises to form a gas zone, oil and water drain down to the horizontal producer. Application of GAGD for IOR in naturally fractured reservoir is discussed here based on some facts and figures.
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