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  1. FATS AND OILS Presented by: Group 2
  2. FATS SIMILARITIES OILS Liquid at room temperature Unsaturated fats belong in oils Unsaturated fats can improve cholesterol levels Solid at room temperature Saturated Fats are solid fat Saturated Fat can increase cholesterol levels Both are glycerol esters Have glycerol backbone and fatty acid chains Both are called lipids
  4. According to Appearance Visible Fat- visually distinctive such as beef tallow, butter, coconut oil, etc Invisible Fat- indistinguishable unless separated by chemical means. Examples are fats in avocado, egg yolk, and lean meats.
  5. Plant vs Animal Plant fats have generally more unsaturated fatty acids. Plant oils have no cholesterol but may be converted to cholesterol inside the body. Monounsaturated fatty acids- canola, olive and peanut Polyunsaturated fatty acids- corn, canola, cottonseed, sunflower, soybean, and safflower. Animal fat has predominantly saturated fatty acids. Only animal fats have cholesterol. Saturated fatty acids, those with no double bonds in the carbon chain are butter, lard, beef tallow, coconut oil and palm kernel oil ACCORDING TO SOURCE
  6. Plant vs Animal ACCORDING TO SOURCE Butter- Milk Lard- Fatty tissues of pork Beef Tallow (Suet)- Fatty tissues of beef Fish Oils- Fatty tissues of fish Fish Liver Oils- Fish Liver Chicken Fat- Chicken Coconut Oils Palm Kernel Oil Palm Oil Soybean Oil Rice Bran Oil Cottonseed Oil Olive Oil Peanut Oil Safflower Oil Sesame Oil Rapeseed Oil Canola Oil Cocoa Butter Combination Oils Specialty Oils (Avocado Oil, Aryan Oil, etc.)
  7. Frying Oils Shortening Spread Salad Dressing Topping Flavoring Nutritional Supplement 1. 2. 3. 4. 5. 6. 7. According to Culinary Use
  8. 9 calories per gram Calories from fat should not exceed 30% of total caloric requirement Excess fats become fat deposits which is responsible for obesity Filipino's consumption of fats and oil is low at 15g/day Bicol Region has highest intake of fats and oils (23g/day) because Central Visayas has lowest consumption at of gata. 8 grams per day. Nutritional Importance
  9. Carry fat soluble vitamins A,D,E and K Insulates body organs from extreme temperatures Necessary to maintain cell structures Sources of essential fatty acids EFA (Linoleic and Linolenic) EFA are converted to prostaglandins necessary for immune system. Linoleic Acid (LA)- parent molecule of omega-6 fatty acids including arachidonic acid (ARA) Alpha-Linolenic Acid (ALA)- parent molecule of omega-3 fatty acids including docosahexaenoic acid (DHA). ARA and DHA are critical for brain development of infants. Nutritional Importance
  11. CHEMICAL COMPOSITION OF FATS AND OILS Triglycerides -glycerol esters of free fatty acids wherein all 3 carbons in the glycerol backbone are attached to the fatty acid. -Most naturally occurring fatty acids have straight even number chains with only hydrogen attached. -Fatty acids may be saturated or not. -Degree of unsaturation has other nutritional and culinary implications. -It affects physical properties, especially melting point -Fats and oil may differ from one another with respect to the position of the fatty acid, the glycerol backbone, and other factors.
  12. CHEMICAL COMPOSITION OF FATS AND OILS Diglycerides and Monoglycerides Monoglyceride- when only one of the 3 carbons of the glycerol is esterified with a fatty acid Diglyceride- When 2 of the 3 carbons are esterified Mono and Diglycerides functions as emulsifiers due to the hydrophilic and hydrophobic ends of their molecules. The free hydroxyl interacts with water and the hydrocarbon chain interacts with the oil.
  13. CHEMICAL COMPOSITION OF FATS AND OILS Phospholipids -a combination of a lipid and phosphate group. -one of the carbons in the glycerol backbone attached to a phosphate -polar substance -occur alongside proteins and lipoproteins in tissues where they're located -Lecithin- most abundant phospholipid in cell membranes Vitamins and Minerals -the fat-soluble Vitamins A,D,E,K -carotenes and chlorophyll may also be present in oils -refined oils have no more pigment due to bleaching process done during refining.
  15. PHYSICAL PROPERTIES OF FATS AND OILS physical and chemical configuration of fats and oil determine its properties and reaction Solid fat is composed of crystal structures of straight chain fatty acids suspended in oil Physical Structure the proportion of fat in crystalline form to suspending oil is expressed as solid fat index (SFI). Solid Fat Index
  16. PHYSICAL PROPERTIES OF FATS AND OILS if there are fewer molecular species, the crystals will be unstable and larger crystals will form whereas if there are more molecular species, the resulting crystals will be smaller. Polymorphism the property of fat that allows it to be molded or pressed into various shapes without breaking. Plasticity
  17. PHYSICAL PROPERTIES OF FATS AND OILS the temperature at which a solid fat is changed into liquid. melting point range depends on the SFI factors determining the SFI are chain length, degree of saturation, configuration at double bonds of unsaturated fatty acids, and the number of molecular species. melting point increases as the number of carbons in its hydrocarbon chain increases and as the number of double bond decreases. the greater the degree of unsaturation, the lower the melting point. Melting Point
  18. PHYSICAL PROPERTIES OF FATS AND OILS the temperature at which a liquid fat is changed to solid. always lower than the melting point Solidification Temperature natural fats are insoluble in water, slightly soluble in lower alcohols and readily soluble in non-polar solvent Solubility
  19. PHYSICAL PROPERTIES OF FATS AND OILS Oil is lighter than water. Oil's density- 0.90 to 0.92 grams per cubic meter Specific gravity is defined as the ratio between the density of a substance and that of water. The density of water is 1.0 so that gravity and density has the same value Density and Gravity
  20. PHYSICAL PROPERTIES OF FATS AND OILS the measure of the ability of a substance to bend light as it passes through it. the clearer the substance, the smaller its refractive index is. In fats and oils, refractive index decreases with increasing temperature Refractive Index the ability of free fatty acids, mono and diglycerides to bridge water and oil molecules useful in emulsification Surfactant Properties
  21. PHYSICAL PROPERTIES OF FATS AND OILS the ability of the fat/oil to withstand heat without undergoing deterioration. . Thermal Stability the temperature at which fat deterioration is sufficient to produce bluish smoke. much higher than the boiling point of water. Frying temperatures- 170° to 195° C. Smoke points of fats and oils are beyond the temperature used in frying. Smoke Point
  22. PHYSICAL PROPERTIES OF FATS AND OILS Pyrolysis- heating oil causes molecular breakdown with or without contact with food Oxidation- combination of heat and oxygen at the surface causes molecular breakdown at the point of unsaturation and ultimately development of rancidity Hydrolysis- water reacts with oil and splits ester bridge between fatty acid and glycerol Reaction with Food Residue- residue from the food being fried reacts with fat and contributes to deterioration. 4 WAYS BY WHICH OILS DECOMPOSE DURING HEATING. 1. 2. 3. 4.
  24. CHEMICAL PROPERTIES AND REACTIONS the breaking of the ester linkage between glycerol molecules and the fatty acids resulting in the release of free fatty acids. water is needed is catalyzed by lipases, enzymes naturally present in some fats, and acids with heat Hydrolysis Ester Linkage Reactions
  25. CHEMICAL PROPERTIES AND REACTIONS the formation of soap with the free fatty acid. saponification number is defined as the grams of potassium hydroxide (KOH) required to saponify 1 gram of oil at specified conditions. Saponification Ester Linkage Reactions the transfer of fatty acid from the glycerol to another alcohol .involved in the production of mono and diglycerides. Interesterification
  26. CHEMICAL PROPERTIES AND REACTIONS the reaction is used in commercial preparation of shortening where a variety of fatty acid molecules is desired to increase plasticity Rearrangement Ester Linkage Reactions another industrial reaction that involves the replacement of fatty acid by acetate .production of emulsifiers and food colors Acetylation
  27. CHEMICAL PROPERTIES AND REACTIONS the reaction is involved in oxidative rancidity the removal of a hydrogen atom from the electron adjacent to a double bond resulting in the formation of free radical, which is highly reactive. Oxidation Reactions involving Double Bond the ability og halogens to be added to a double bond in an unsaturated fatty acid. the basis for the iodine value determination, a degree of unsaturation of fatty acids. Halogenization
  28. CHEMICAL PROPERTIES AND REACTIONS the reaction used in commercial production of hydrogenated oil Highly unsaturated oils are heated with hydrogen under pressure in the presence of a catalyst to saturate the double bond carbons used to increase hardness in fats to make them more suitable for use as margarines and shortenings. Side effect of hydrogenation is isomerization, resulting in conversion of cis to trans configuration. Hydrogenation/Isomerization Reactions involving Double Bond
  30. RANCIDITY OF FATS AND OIL results in the formation of free fatty acids and soaps cause by either reaction of lipid and water in the presence of a catalyst or by the action of lipase enzymes Hydrolytic Rancidity results from a more complex liquid oxidation process Initiation or Induction Phase Propagation Phase Termination Phase Oxidative Rancidity
  31. RANCIDITY OF FATS AND OIL the initial quality of fat or used for manufacturing the product conditions used to manufacture the product storage conditions surface area exposed to atmospheric oxygen presence of transition metals concentration of active lipoxidase application of appropriate of synthetic or natural preservatives presence of chemical oxidizers Factors Affecting Oxidation of Fats and Oils
  32. RANCIDITY OF FATS AND OIL peroxides and hydroperoxides are the predominant reaction products. Increased peroxide and hydroperoxide concentrations will lead to increasing concentrations in aldehydes, ketones, hydrocarbons, and other termination phase products. The rate of decrease varies with storage conditions, packaging, and original fat content. It is best to rely on sense of smell to determine if rancidity has set in. Tasting can determine early rancidity. Reaction Products of Oxidation
  33. MEASUREMENT OF RANCIDITY 2 types: predictive test and oxidation indicator tests Predictive testing- ex: deterioration of iodine value Oxidation Indicator Tests- peroxide value, TBA, anisidine, and free fatty acids Chemical Methods detect typical smells such as acetaldehyde and phenolic substances Sensory Methods
  34. Saturated aldehydes, 2-enals, and 2-dienals produced in the termination phase of lipid oxidation can be detected by reaction with 2-thiobarbituric acid. produces red color which can be measured using spectrophotometer TBA Tests MEASUREMENT OF RANCIDITY measure of the concentration of peroxides and hydroperoxides formed in the initial stages of lipid oxidation. Peroxide Value
  35. can be determined by titration this is an indication of hydrolytic rancidity Free Fatty Acids (FFA) MEASUREMENT OF RANCIDITY when hydroperoxidase break down, they produce volatile aldehydes leaving behind a non-volatile reaction product that can be measured by reaction with anisidine. Anisidine Value
  36. effective scavenger of peroxyl radicals Vitamin E PREVENTING RANCIDITY compounds that delay rancidity and flavor deterioration associated with oxidation. either from natural or synthesized products useful only for oxidative rancidity radical scavengers Antioxidants
  37. propyl gallate, butylated hydroxyanisole (BHA), butylated hyroxytoluene (BHT), and tertiary butyl hydroquinone (TBHQ). Phenolic Antioxidant PREVENTING RANCIDITY donates hydrogen returns hydrogen atom removed from initial process to form unreactive ascorbic radical. Vitamin C *Antioxidants do not stop the development of oxidative rancidity but can delay it.
  38. any form of altering the gaseous composition inside a food package Modified Atmosphere Packaging PREVENTING RANCIDITY substance that helps antioxidants but in themselves are not antioxidants Chelating Agents lowering storage temperature can delay rancidity development Storage Temperature Control
  40. ANIMAL; FAT PRODUCTS fat or cream that is separated from other milk constituents by agitation or churning. 18% water dispersed in 80% fat with small amounts of proteins as emulsifiers Butter fatty tissues of hog are chopped into small pieces and heated with or without water. Wet rendering is more common In the Philippines, Lard is a by-product of chicharron making. Utilized mostly as flavoring ingredients or flavor carriers. Lard
  41. ANIMAL; FAT PRODUCTS beef tallow is dry rendered form fatty tissues of beef Tallow of interest due to omega fatty acids Fish Oils
  42. PLANT FAT PRODUCTS oil obtained by pressing the ripened olives graded according to acidity Olive Oil usually winterized Winterization- a process which subjects the oil to a low temperature where higher melting point glycerides are crystallized then filtered off. Cottonseed Oil remove from oil containing seed fruits or nuts by various processes, by solvent extraction and by combination of these. Vegetable Oil
  43. PLANT FAT PRODUCTS major edible oil in the U.S.A. Soybean Oil oil obtained from the germ of the corn endosperm linoleic (55%) and oleic (29%) polyunsaturated fat. used as frying oil and salad oil Corn Oil obtained from genetically modified rapeseed. modification reduced erucic acid from 20-40% to less than 2% used for frying, salad dressing, and shortening Canola Oil
  44. PLANT FAT PRODUCTS shortening is made by hydrogenation of refined oil Vegetable Shortening substitute for more expensive butter prepared from a mixture of vegetable oil that is hydrogenated pasteurized then churned Margarine extracted from dried coconut meat called copra composed mostly of saturated medium chain fatty acids. About 50% lauric acid and 20% myristic Coconut Oil
  45. PLANT FAT PRODUCTS 50% lauric acid Destroys lipid membranes in a variety of microorganisms and viruses Human breast milk protects infants from illnesses. Benefits of Coconut Oil urged to avoid due to its saturated fatty acid content which was linked in the production of low density lipoprotein (LDL) or bad cholesterol. Negatives of Coconut Oil
  46. PLANT FAT PRODUCTS produced without the use of chemicals derived directly from coconut milk oil is extracted by natural fermentation and separated by centrifuge and filtration Virgin Coconut Oil palm kernel oil- seed oil, has fatty acid composition similar to coconut palm oil- rich in vitamin E, is extracted from the fruit and constitutes equal amounts of saturated and unsaturated fatty acids. Indonesia and Malaysia are the largest palm oil producers. Palm Oil and Palm Kernel Oil
  48. FUNCTIONS OF FATS AND OILS snack food and fast food industries are the major industrial users of frying oils. Snack Food Industry Oil blanching is an industrial process and is better known as first fry. This is also a drying process Blanching Medium A variation of frying which is done at very low (below 100%) temperatures is also known as oil poaching. Low Temperature Frying
  49. FUNCTIONS OF FATS AND OILS one of the most important functions of fat is to tenderize baked products that otherwise would be a tough mass firmly held by gluten. Shortening Oil can either be the dispersing medium or the dispersed phase. Emulsion Structure Fat affect smoothness of crystalline candies and frozen desserts by retarding crystallization Fat affect gelatinization process and contributes to juiciness in meat and foam structure of whipped cream. Texture Effect
  50. FUNCTIONS OF FATS AND OILS Fats and oils are used to prevent food from sticking to the pan. Spray or Greasing Fat is an efficient flavor carrier Flavor Effect Butter and yellow margarines are used for a more appetizing color/appearance. Color Effect Fat is a raw material for emulsifiers and is also a source of fatty acids for food supplements Fat as Sources of Ingredient/Supplement
  52. FATS SUBSTITUTES mixture of compounds called esters made by combining sucrose esters and fatty acids. EX: Olestra Olestra is currently used as frying medium for savory snacks and shortening Sucrose fatty acid polyesters (SPE's) similar to SPE's but their molecular size is smaller. they are partially or fully absorbed providing up to 9 cal/gram to diet used as emulsifiers and stabilizers Sucrose fatty acid esters (SFE's) Fat-Based Substitutes
  53. FATS SUBSTITUTES derived from a variety of protein sources such as eggs, milk, whey, soy, and wheat gluten. these proteins undergo microparticulation Protein-Based Fat Replacers Carbohydrate-Based Fat Replacers carbohydrates including gum, starches, pectins, and cellulose have been used as thickening agents to add bulk, moisture and textural stability to variety of foods.
  55. STORAGE OF FATS AND OILS Avoid exposure to oxygen, light, and heat. Refrigeration is a good option. Always cover oil container. Used oil should be strained to remove food particles that have been broken off during frying General Rules to Maximize the Shelf Life of Fats and Oils Oil is subject to 2 kinds of deterioration: hydrolytic rancidity and oxidative rancidity. Avoid water and oxygen to prevent these reactions from happening.
  56. STORAGE OF FATS AND OILS Do not overheat oil. Watch out for the smoke point. When oil starts to smoke, lower the heat. Never leave heating oil unattended. Do not allow children and pets to go near fryers while in use. Cool heated oil before transferring to any container. Do not transfer hot oil to plastic containers Clean spilled oil immediately Have fire extinguisher in the kitchen. Never use water to put out fire. Use baking soda. Safety Precautions:
  57. STORAGE OF FATS AND OILS Do not throw oil in the drain. Dispose it as solid waste in a tightly sealed container Use absorbent material such as soil or sand if there are spills Large quantities of used oil are best taken to gasoline station that has proper disposal procedure. Disposal of Used Oils
  59. Abedejos, Jhonacel Gail Bravo, Ma. Jacinta Bucong, Andrelle Jan Butcon, Czaira De Los Santos, Andrea Martinez, Ronna Alieza Mae Najera, Elyssa Tan, John Carl Taray, Gizelle Kate Ybiosa, Yuljix GROUP 2