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.
Rice Bran Essay Example
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 it is called drying oil. According to data Rice bran oil is a semi drying oil. Acid Value: In chemistry, acid value (or “neutralization number” or “acid number” or “acidity”) is the mass of potassium hydroxide (KOH) in milligrams that is required to neutralize one gram of Oil or fat. The acid number is a measure of the amount of carboxylic acid groups n a Oil or fat, such as a fatty acid, or in a mixture of compounds. In a typical procedure, a known amount of sample dissolved in organic solvent is titrated with a solution of potassium hydroxide with known concentration and with phenolphthalein as a color indicator. The acid number is used to quantify the amount of acid present, for example in a sample of biodiesel. It is the quantity of base, expressed in milligrams of potassium hydroxide, that is required to neutralize the acidic constituents in 1 g of sample. Acid value indicates the proportion of free fatty acid in the oil or fat.
The normal Acid value for most samples lies within 0. 5. The acid number is used to quantify the amount of acid present, for example in a sample of biodiesel. It is the quantity of base, expressed in milligrams of potassium hydroxide that is required to neutralize the acidic constituents in 1 g of sample. Classification of oil: Depending on sources, Oils are classified as – a) Animal fats and oil: These are obtained from animal sources. Example: Cod-liver oil, butter. b) Vegetable fats and oil: These are obtained from vegetable sources. Example: Rice bran oil, Coconut oil, Soybean oil, palm oil. etc.
Depending upon the nature of carbon chain and iodine value vegetable oils are classified asa) Non drying oil: These oils contain least proportion of unsaturated acid containing two or three double bond. Non drying oil don’t absorb oxygen from air and don’t dry up to form a hard skin. Range of Iodine value is below 90-95. Example: Olive oil (85), Castor oil (85), Coconut oil (8. 2-9. 6), Palm oil (52). b) Semi drying oil: These oils contain intermediate proportion of unsaturated acid containing one or two double bond. Semi drying oil absorbs oxygen from air slowly and thickens after keeping exposed to air for some time, But don’t dry up.
Various edible oils are Rice bran oil, Soybean oil, palm oil. Etc. are employed for salad, dressings other table uses and for cooking purposes. b) Inedible oil: this oil is used for soap manufacturing. The drying oil industries, including paints and varnishes. Example: Tallow, Coconut oil, Palm oil etc. Oils are classified on the presence of nature: a) Petroleum oil: A naturally occurring oil that consists chiefly of hydrocarbons with some other elements such as sulfur, oxygen and nitrogen. In its unrefined form petroleum is known as crude oil.
Sometimes also called rock oil. These oils are obtained from crude petroleum by distillation. The number of carbon atom ranging from C1 to C40. The main functions are Refinery gas(Methane), Gasoline(C5 to C8) BP: 40 to180oC, Kerosene( C11 to C12) BP: 160 to250oC, Diesel oil (C13 to C25) BP: 220 to350oC, [BP= Boiling point] b) Essential oil: Essential oils are volatile oils with pleasant odour and are obtained from various plants excudes and flowers by stem distillation. It must contain isoprene unit.
Linalool contain alcoholic group Citral contain aldehyde group Eucalyptus contain ester group Example: Citrus oil, flower oil (e. g. Rose, jasmine) and cloves. etc Uses of Essential oil: Making perfumes, toilet soaps, tooth pastes, and manufacturing inks, varnishes, greases etc. c) Fatty oil: Fatty oils are obtained from vegetable and animal sources. Chemically they belong the fats and fatty oils are the glycerides of fatty acids have low melting point. Example: Rice bran oil, Coconut oil, Soybean oil, palm oil, etc.
Differentiate between Oils Fats and waxes Fat Oil Waxes Tri glycerol ester of fatty acid Tri glycerol ester of fatty acid Ester of mono hydric alcohol with higher fatty acid Solid at Room temp Liquid at Room temp Crystalline Solid at Room temp Saturated fatty acid Un saturated fatty acid Saturated or Un saturated fatty acid Non insulator Non insulator Insulator Contain a small amount of alcohol Contain a small amount of alcohol Contain a large amount of alcohol Rice bran oil: Rice bran oil is extracted from the bran layers of rice. Rice bran oil inherently contains a high level of gamma oryzanol, a natural mixture of ferulic acid esters.
Oryzan is processed by a non-conventional vegetable oil refining technique to provide several unique properties. It retains much of the oryzanol that is naturally present in the crude oil. Due to its strong antioxidant properties, oryzanol retards oil degradation at elevated temperatures. This results in oil with an extended fry-life and fried foods with improved storage stability. While Oryzan rice bran oil can be used alone, it can also be blended with other oils to improve their frying performance. Information of Rice bran oil: Rice bran oil contains the highest amount of all natural vitamin E in liquid form.
It is also rich in phytic and ferulic acids, which promote microfoliation (a gentle form of exfoliation) while helping balance melanin production. It also contains proanthrocyanidins, which protect collagen and elastin to ensure suppleness of the skin. Rice bran oil is particularly high in fatty acids. It is excellent for mature, delicate or sensitive skin. Rice Bran Oil is recommended for skin care and massage products. It’s shelf life is six months to one year. An emollient oil similar to other nonvolatile plant oils. Rich in vitamin E. It has a smaller molecule than wheat germ oil making it much easier to penetrate the skin.