Rice Bran

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Rice Bran

By | October 2012
Page 1 of 8
An Assignment on Rice Bran Oil Technology

Oil: Oils are esters of glycerol and fatty acid. In other words, oils are tri-glycerol ester of fatty acid. Hence ester of glycerol is known as glycerides and fatty acids both are saturated and unsaturated. Oils are liquid at ordinary temperature. Example: Rice bran oil, Coconut oil, Soybean oil, palm oil. Etc. Fats: Fats are same as oil, i.e. Fats are esters of glycerol and fatty acid, except that fat is solid at ordinary temperature. The melting point above 20°C. Example: Butter, Tallow, Lard etc. Waxes: Waxes are esters of long chain fatty acid. Usually contain 24-28 carbon atoms with long chain primary alcohol containing 16-36 carbon atoms or with alcohol of the steroid group. Waxes are non crystalline. Example: Bees wax, Carnauba wax, opal wax. Etc. Properties of oil: 1. At room temperature oils liquid. 2. Oils contains large proportion of unsaturated fatty acid. 3. Oils are insoluble in water but readily soluble in Hexane, ether, benzene, Carbon tetra chloride, etc. 4. Oils are easily hydrogenated like alkenes. 5. Oils react with Iodine, chlorine in aqueous alcoholic solution to form iodo-chloro derivatives. Terms related Definitions: Iodine value: Iodine value may be defined as the number of gm of Iodine that will add across the Carboncarbon double bond in hundred (100) gm of the fats or oils. Or simply the amount of iodine (in gm) absorbed by 100gm of fat. Significance: Iodine value is a measure of the extent of un saturation in fats or oils. The greater the number of double bond more iodine is required to break this bonds.ie. Iodine value is more. For example Oleic acid has one (C=C) double bond and it iodine value is 85whereas Linoleic acid contain two (C=C) double bond has iodine value is 181. Iodine value of Rica bran oil is 99-108. If Iodine value is below 90 then it is called non drying oil, If iodine value is above 90 and below 140 then it is called semi drying oil and if iodine value is above 140 then...