2 Where is the oil located? Plants use stored oil as food for germinating embryo, caloric content is high so is efficient storage material. Double that of carbohydrates and proteins.Oil can be stored in endosperm (castor, coconut), cotyledons (peanut, soybean), scutellum (corn), fruit pulp (palms and olives).Seeds have organelles called as glyxosomes that convert fatty acids into carbohydrates during germination.
3 Oils Mainly hydrocarbons made up of Glycerol (backbone) with three fatty acids chemically bonded to it - triglycerides
5 UnsaturationThe number of double bonds determines the level of saturation.Vegetable oils are complex mixtures and saturation levels cannot be calculated directly very easily;% saturation is determined by Iodine method,Iodine breaks ='s and is incorporated. Amount of Iodine left over is determined. Iodine values range from 7 to > are called fats (solid at room temperature) and higher values correspond to more unsaturation.
10 Soap makingSoap is salt of fatty acid+3NaOH 3 RCOO- Na++
11 Soap Making Water lye (Base) Add oil or fat Glycerol and fatty acids separateFatty acids will react with base to form salt of fatty acidHead which is soluble in waterTail soluble in oil
12 Oil Paints and Varnishes Drying or semidrying oils (linseed & tung oil)oil paints are boiled with heavy metal containing compounds (Mg, Co, Pb) which help oils absorb oxygen and form a hard film;varnishes are produced by mixing boiled oils with resins or gums;enamels are varnishes + pigments;paints do not contain gums or resinsLatex paints - alkyd resins which are manufactured from fatty acids cleaved from vegetable oils, water soluble
13 Linoleum and JojobaMade up of Oils + gums + synthetic resins + pigments;oils are "blown" which thickens them and makes them soluble in petroleum oils (resins)linoleum is not used much in U.S. anymore.Jojoba - oils is esters rather than triglycerides, originally thought to be good substitute for sperm oil but is not because of high temperature breakdown; however is useful in medicine and cosmetics.
14 Extraction Grinding with stones - cold pressing – high quality Steam driven stone presshot pressingScrew press - continuous feedSolvent extraction - follows screw press, hexane
15 Refining Removal of free fatty acids Degumming - removes mucilaginous materialBleaching - removal of pigmentsDeodorized - steam heatingWinterize - prevents clouding by chilling oil and filtering out particles.Hydrogenation - yields vegetable lards, margarine and cheese substitutes
16 Drying Oils High in double bonds in FA Linseed oil - Linum usitatissimum, seeds, water-repellent glazemostly non-edible oilsdue to unpleasant flavorCyanogenic glycosidesandrapid rancidity due to lots of double bonds.also source of flaxTung oil - Aleurites (Euphorbiaceae), seeds, poisonous (not edible), used in paints, waterproof coverings and caulking. Once grown in U.S. but most now comes from China.
18 Semi-drying Oil Few double bonds in FA Safflower oil - Carthamus tinctorius, thistles, oil is from seeds, used in cooking oils, salad dressings, margarine, high I value so low in calories but oxidizes readilyProduces dyeSoybean oil – Glycine max already covered, stores well, used in salad and cooking oils and artificial "fluffy" products.Sunflower oil - Helianthus annuus - native North American plant but development of large-headed cultivars is largely credited to Russians; used as salad and cooking oil; paints, varnishes and resins; added to diesel fuel. Considered equal to olive oil, used for production of margarines.Corn oil – Zea mays salad dressing and margarines, stable but smokes at high temp.Sesame oil - Sesamum indicum, from Ethiopia, highly resistant to oxidation due an antioxidant compound called sesamolin, most is consumed and produced in Africa, Middle East, India and ChinaCottonseed oil – Gossypium barbedensis byproduct of cotton fiber production, must remove gossypol (toxic to most animals except cows); Wesson oil, hydrogenation ---> CriscoRapeseed oil - Brassica napus, edible oil but possibly toxic, most useful as machine oil as an lubricant
19 Non-drying Oil Peanut oil - Arachis hypogaea, premium cooking oil Olive oil - Olea europea, obtained from fruit pulp,Gentle pressing of the olive – virgin oilFurther pressing – first, second grade oilsHas monounsaturated fat – good for health.Castor oil - Ricinus communisLaxative – ricinoleic acidpoison - ricine (alkaloid) and ricin (highly toxic protein); used in soaps, paints, lubricants
21 Vegetable FatOil palms - Elaeis guinensis, distinct oils are obtained from fruit pulp and seedskept separate due to differences in chemical composition; used in soap, candles, margarine and shorteningsU.S. diets are avoiding fats and palm oils are taboo.Coconut oil - Cocos nucifera, cosmetics and nondairy "dairy" productsAt 20oC becomes semisolid; at 15oC becomes brittleHas free fatty acid – caprylic acid - smellShea butter: Butyrospermum parkit50% saturated fat
22 Relative effect of fats on Total Cholesterol Oil or FatMyristic acid C14:0Palmitic acid C16:0Linoleic acid C18:2Alpha Linolenic Acid C18:3Dietary Cholesterol Delta TC Change in cholesterol levelButterfat1127212731788 Canola oil42210-514 Coconut oil1891674 Corn oil58-870 Grape seed oil873-1196 Lard2677630 Olive oil1388.6 Safflower oil*778-1310 Soybean oil54-908 Sunflower oil*68-1142 * Not high-oleic
23 Wax Long chain alcohol and long chain fatty acid Jojoba wax: Simmondsia chinensisSeeds contain liquid waxSimilar to sperm whale oil