Foodchem Lecture 2 Pictures

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    • "Edible oil shipments"
    • Lipids represent a major food commodity and industrial sector - both in terms of production and processing
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    • "Lipids - hydrophobic"
    • Lipids are characterized by their insolubility in water and other polar solvents and their solubility in non-polar organic solvents such as hexane, chloform or ether
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    • "Lipid extraction"
    • When we exhaustively extract dry biological materials with hydrophobic organic solvents the extract we obtain is commonly termed "Lipid"
    • Lipids are made up a wide variety of chemically and sturcturally diverse hydrophobic constituents
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    • "Glycerol backbone"
    • Fats are esters of fatty acids connected specifically to glycerol. The three Rs are different fatty acids
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    • "Three ester linkages"
    • The three Rs are different fatty acids connected to glycerol via an ester linkage
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    • "Red portion is the ester linkage"
    • Fats are technically termed triacylglycerols, or more commonly triglycerides
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    • "Bees' wax - solid wax"
    • Generally most waxes are formed from longer chain aliphatic fatty acids and alcohols and tend to be solid
    • Most natural waxes have limited food applicatios, the most common being for coating and sealing foods to prevent moisture loss (for cheese) or as a polishing agent (for apples)
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    • "Jojoba plant"
    • Some plats actually produce waxes instead of fats (triglycerides) as a seed energy store for germination
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    • "Jojoba oil"
    • Liquid wax, largely composed of linear esters of mono-unsaturated long chain fatty acids esterified to fatty alcohols
    • Jojoba oil is used extensively in cosmetics and is also used as a low-calorie food ingredient with properties similar to olestra (gives a fatty sensation but provides limited calories as it cannot be attacked enzymatically, i.e. digested)
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    • "Cholesterol"
    • In the wax sub-category - it is made up of fatty acids esterified to a complex alcohol
    • Red portion is the OH group
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    • "Cholesterol ester (wax)"
    • In the wax sub-category - it is made up of fatty acids esterified to a complex alcohol
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    • "Vitamin A ester (wax)"
    • Present only in minute quantities in food systems so they are of little consequence functionally to the bulk lipid, but they are important because they are biologically active an play important roles in that regard
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    • "Phosphatidic acid"
    • In phospholipids "x" is usually a nitrogenous base but can also be a sugar-like moiety (inositol)
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    • "Common phosphate linked groups conjugated to phosphorous in phospholipids"
    • We can to some degree subivide phospholipids based on their phosphate linked moiety
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    • "Lecithin (phosphatidyl choline)"
    • In lecithins, choline is the "x" constituent attached to the phosphate group
    • Lecithins are a sub-class of phospholipid compounds, there being hundreds of thousands of different individual lecithins depending on their fatty acid composition
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    • "Cephalin - phosphatidic acid is conjugated to ethanolamine"
    • Ethanolamine is the "x" group in this type of phospholipid
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    • "Phosphatidyl inositol"
    • Has a cylclohexitol or cyclohexane hexol side chain
    • Example of a phospholipid sub-category with a non-nitrogenous group attached to the phosphatidic acid
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    • "Simple glycolipid"
    • Contains most of the elements of triglycerides (glycerol and 2 fatty acids) but a sugar has replaced the third fatty acid and there is no phosphorous
    • Sugar provides some polarity to the molecule
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    • "General sphingolipid structure"
    • Similar to a phospholipid but also contains nitrogen and has no ester linkage in the side chains
    • Sphingolipids oftern contain either phosphate or carbohydrate - hence can be either classified as a phospholipid or a glycolipid
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    • "A sphingomelin - has phosphocholine attached to ceramide base"
    • Similar to a phospholipid but also contains nitrogen and has no ester linkage in the side chains
    • Sphingolipids oftern contain either phosphate or carbohydrate - hence can be either classified as a phospholipid or a glycolipid
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    • "Sphingo lipid - Galactose attached to the ceramide base"
    • Glycolipids and sphingolipids are commonly associated with cell membranes in both plants and animals
    • These membrane lipids are structurally important for permeability and transport in and out of cells, but have little value to food science
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    • "Lipoprotein complex"
    • Very complex structured protein-lipid complexes, their actual detailed structure is still being studied
    • The associated lipids can be either from the simple or the compound categories
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    • "Fatty acid structure"
    • FA = short to long chain aliphatic hydrocarbon with a carboxyl group at one end and which may contain double bonds
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    "Presence of FFA in fats and oils can lower their smoke point when used for frying"
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    • "Isoprene base unit"
    • 5 carbons, 2 conjugated double bonds
    • Terpenes are made up from these fundamental units
    • "Oxygenated"
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    • "Monoterpene - Limonene"
    • Terpenes, essential oils typically obtained by steam distillation from plant materials (like leaves)
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    "Steam distillation"
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    • "Xanthophylls"
    • Oxygenated derivatives of carotenes
    • Important hydrophobic food color constituents
Author
Morgan.liberatore
ID
134677
Card Set
Foodchem Lecture 2 Pictures
Description
Foodchem Lecture 2 Pictures
Updated