Animal and Vegetable Fats, Oils and Waxes Overview

Triacylglycerols

Esters of glycerol and three fatty acids.

Waxes

Esters of long-chain fatty acids and alcohols; contain carbon chain ranging from 24-28

Lipids

Broad group of nonpolar chemical substances.

Nonpolar Lipids

Insoluble in water, soluble in organic solvents.

Polar Lipids

Amphipathic, includes fatty acids and phospholipids.

Phospholipids

Include lecithins and sphingomyelins.

Fatty Acids

Building blocks of triacylglycerols, even carbon atoms.

Trivial Names

Common names indicating source of fatty acids.

Shorthand Notation

Number of carbons followed by double bonds count.

IUPAC Names

Systematic naming based on carbon count and bonds.

Cis Configuration

Hydrogens on the same side, causing a bend.

Trans Configuration

Hydrogens on opposite sides, maintaining straight chain.

Acylglycerols

Esters formed from glycerol and fatty acids.

Monoacylglycerols

Glycerol with one fatty acid, more polar and effective as surfactants

Diacylglycerols

Glycerol with two fatty acids, used as emulsifiers and in various food products

Triacylglycerols

Glycerol with three fatty acids, commonly found in dietary fats and oils, serving as a major form of energy storage in the body.

Stereospecific Numbering System

Indicates fatty acid positions on glycerol, uses the prefix “sn”

Emulsification

Stabilizes mixtures of oil and water in food products and cosmetics.

Nutritional Aspects

Triacylglycerols provide 9 kcal/g energy.

Melting Points

Depends on fatty acid composition and structure.

Saturated Fatty Acids

Higher melting points than unsaturated counterparts.

Chain Length

Longer chains increase melting points.

Double Bonds

Presence and position affect melting points.

Elaidic Acid

Trans isomer of oleic acid; melting point of 45°C

Oleic Acid

C18:1 fatty acid with one double bond; melting point at 13.4°C

Stearic Acid

C18:0 fatty acid, no double bonds.

Polymorphism

Ability of substance to exist in multiple crystalline forms.

Alpha (α) Crystals

Least stable, smallest size, forms at low temperatures.

Beta Prime (β') Crystals

More stable than alpha, larger size, formed during cooling.

Beta (β) Crystals

Most stable, largest size, forms under slow cooling.

Cooling Rate

Influences crystal formation; rapid favors alpha crystals.

Fatty Acid Composition

Type affects crystallization; saturated forms stable structures.

Processing Conditions

Mechanical processes alter crystallization behavior.

Additives

Emulsifiers and stabilizers modify crystallization process.

Texture and Mouthfeel

Crystal structure influences food product texture.

Shelf Life and Stability

Crystal forms impact rancidity and overall quality.

Functional Properties

Affects cooking, baking, and food preparation functionality.

9 kcal/g

Fats provide ______, essential for energy intake.

Fat-Soluble Vitamins

Includes A, D, E, K; essential for health.

Essential Fatty Acids

Omega-3 and omega-6; body cannot produce them.

Dietary Lipids

contribute to the structural integrity of cell membranes and are involved in signaling pathways that regulate various physiological processes.

Unsaturated fatty acids

particularly those from plant sources, have been associated with reduced risks of cardiovascular diseases.

Hydrophobicity

Waxes are largely insoluble in water.

Long carbon chains

_______ lead to solid state at room temperature.

plants, animals, and microorganisms.

Sources of Waxes

cutin

the cuticle of leaves is composed of ____, a type of wax.

Beeswax

a well-known example of animal-derived wax, produced by honeybees for building honeycomb structures.

Terpenes

large and diverse class of organic compounds produced by plants, derived from isoprene.

Monoterpenes

Composed of two isoprene units (C10).

limonene

found in citrus fruits

pinene

found in pine trees

Sesquiterpenes

Composed of three isoprene units (C15).

farnesene and humulene

contribute to the aroma of hops and various essential oils.

Diterpenes

Composed of four isoprene units (C20).

phytol

a precursor to vitamin E.

Carotenoids

Pigments responsible for red, orange, yellow colors of fruits and vegetables.

Carotenes

Purely hydrocarbon carotenoids

beta-carotene and alpha-carotene

carotenoids that are precursors to vitamin A.

Xanthophylls

Oxygen-containing carotenoids

lutein and zeaxanthin

carotenoids that are important for eye health.

Cholesterol

vital component of cell membranes, precursor for steroid hormones and bile acids.

Steroids

a class of lipids characterized by a core structure of four fused carbon rings; synthesized from cholesterol.

Steroid Hormones

Regulate metabolism, immune response, reproductive functions; cortisol, testosterone, and estrogen.

Bile Acids

Essential for digestion and absorption of dietary fats.

Global Vegetable Oil Production

Over 50% enters international trade.

Soybeans

Largest source of visible fats and oils.

US

the largest soybean producer, responsible for 44% of global production.

Visible Fat Consumption

60% from meat and dairy, 40% from cooking oils, shortenings and margarine.

Vegetable Fats

1/3 of visible fats in 1940 to over 90% of visible fats by 1985.

1.5-2

The world needs an additional ______ million tons of fats and oils annually to keep up with population growth.

Animal Fats

Fats derived from animal sources, less prevalent now.

Oilseed

Seeds used for extracting oils, e.g., soybeans.

Canola

Low erucic acid-low glucosinolate seed developed in the 1960s and 1670s by Canadian scientists.; replace traditional rapeseed.

High-Oleic Acid Oils

Oils from sunflower and safflower seeds, healthier.

Flaxseed

Modified for reduced linolenic acid content.

Gossypol

Toxic compound in cottonseed, reduced in glandless varieties.

Oil Palm Biotechnology

Investments by Palm Oil Research Institute of Malaysia (PORIM) to enhance oil palm production.

Oilseed Extraction Plants

Facilities processing 3,000-4,000 tons of oilseeds daily.

high-oil-content seeds

>30% oil

low-oil-content seeds

<30% oil

Seed Cleaning

Removes trash to prevent moisture and free fatty acids (FFAs) formation.

Dehulling

Process of removing hulls to reduce fiber content.

Seed Heating

Heats seeds to prevent phospholipase activity.

Shallow Bed Extractors

Use a thin layer of flakes for solvent extraction. 0.5 - 1 m thick layer of collets/flakes

Deep Bed Extractors

Carousel with pie-shaped cells (basket) for efficient oil extraction.

Screw Pressing

Pretreatment to make seed tissue brittle for pressing.

Olive oil

is primarily extracted from the fruit of the olive tree (Olea europaea) and is highly valued for its flavor and health benefits.

Cold Pressing

Traditional method involves crushing olives to produce a paste, then mechanically pressed to extract oil.

Centrifugation

Modern method of extracting, olive paste is spun at high speeds to separate oil from water and solids.

Solvent Extraction

Uses hexane for lower-grade oil extraction. extract residual oil from the pomace (the solid remains after pressing).

Coconut oil

derived from the meat of mature coconuts (Cocos nucifera) and is known for its distinctive flavor and health benefits.

Expeller Pressing

Heated coconut meat pressed for higher oil yield.

Palm oil

extracted from the fruit of the oil palm tree (Elaeis guineensis) and is one of the most widely produced vegetable oils globally.

Mechanical Extraction

Steaming palm fruit to facilitate oil separation.

Palm kernel oil

extracted from the seeds of the oil palm fruit and has different properties and uses compared to palm oil.

Free Fatty Acids (FFAs)

Unbound fatty acids that can spoil oils.

Batch-Type Extractors

Older design, now rarely used in extraction.

Protein Meals

Byproduct of oil extraction, used for animal feed.

Mechanical Pressing

Method to extract oil by crushing fruit.

Digestion

Mashing fruit to break down cell walls.