Ppt0000008 - Physical characteristics Melting point Smoke,...

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Melting point Smoke, flash, & fire points Cloud point Solid fat content Physical characteristics Chemical characteristics Free fatty acids; Peroxide Value TBARS; Oxidative stability Fatty acid composition & trans -fat analysis
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Crude unrefined soybean oil 95-97% triglyceride 2.5% phospholipids 0.5% free fatty acids 0.005-0.02% Tocopherols 0.005-0.02% Phytosterols Composition Are removed by refining
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Refining of vegetable oils Crude Soybean Oil Degumming Alkaline treatment Deodorizer Bleaching Fully refined (100% triglyceride) Phospholipids removed as gum Free fatty acids removed as soap Distillate (0.1-0.4% of crude oil) Contains 6% tocopherols and 5.5% phytosterols Soy oil as an example
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The oil shall be clear at 70°-85° F The oil shall be clear at 70°-85° F Free fatty acid ≤ 0.05% w/w Free fatty acid ≤ 0.05% w/w Flash point shall not be below 250° F Flash point shall not be below 250° F Moisture and volatile matter ≤ 0.10% w/w Moisture and volatile matter ≤ 0.10% w/w Peroxide value Meq/Kg shall not exceed 2.0 Peroxide value Meq/Kg shall not exceed 2.0 National Oilseed Processors Association, 2009
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Use previously discussed crude fat extraction methods –Soxhlet typical Ensure that the samples are visually clear of sediment. Avoid heat, light and air during sample storage (may cause lipid oxidation)
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Melting point - temperature at which we get a change from solid to liquid . Fats are blends of triglycerides so there is no sharp melting point. Examples: Palm oil (fully hydrogenated): 58-60°C Shortening (partially hydrogenated): 46°C Beef tallow: 44°C Cocoa butter: 35°C Peanut oil: 3°C Soy bean oil: -16°C
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Capillary Melting Point : Fat is put into capillary tube, sealed, and then heated slowly in a water bath until completely clear. Wiley Melting Point : Fat is formed into a standard sized disk (1/8” x 3/8”) and then chilled to solidify. Disk placed in alcohol-water bath and slowly heated until the disk becomes a sphere.
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What does it tell us about the lipid? High melting point - higher content of saturated fatty acid, better oxidative stability Beef tallow: 44°C High melting point - higher content of unsaturated fatty acid, low oxidative stability Soy bean oil: -16°C
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Heat
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Ppt0000008 - Physical characteristics Melting point Smoke,...

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