Some details about vegetable oils

Vegetable oils

                     Vegetable oils are liquid at ordinary temperature. They usually contain fatty acid called oleic acid and glycerine. Fatty oils are stored in seeds of many plants. Several fatty oils are edible and used for cooking purposes. Vegetable oils are commonly used for perfuming soaps and beverage products.

1. Sources of oils

               The sources of oils are generally seeds. Groundnut, castor, sesame, mustard, coconut, safflower and soyabean are some of examples for oil yielding seeds. Whereas jasmine oil is extracted from flowers; eucalyptus oil is extracted from leaves; orange oil is obtained from peels of fruits; cyperus oil is obtained from tubers and sandal wood oil is distilled from the roots and the heartwood of sandal wood tree.

2. Oil extraction

               Various methods are employed to extract oil from plant sources. The country treadmill, steam distillation, crushing under pressure and extraction by cold pressure are methods employed in oil extraction. sesame oil is extracted by cold pressure. Castor oil is obtained by solvent extraction method. Coconut oil is obtained by hydraulic pressure method.

3. Safflower oil

               It is obtained from the seeds of safflower plant. Its binomial is Carthamus tinctorius. This plant is cultivated on large scale. It is widely grown in Africa, China and USA. It is a herb growing to a height of one to four feet. The fruit contains a single seed. It contains 24 to 37 percent of oil and 15 to 22 percent of proteins. 

                    Extraction is done by pressure. The fruits are gathered and dried for a few weeks. Pericarp is removed and the seeds are isolated. Oil is extracted from the seeds by crushing and pressure. It is then filtered and refined. 

                   It is mainly used in the preparation of plants, varnish and soap. In India this oil is used as food and for cooking. It does not increase the cholesterol and therefore it is recommended for heart patients. The white paints prepared from this oil do not turn yellow on long exposure.

3. Nutritive value of oils

                Vegetable oils usually contain more amount of fats and proteins. For example sunflower seeds contain 40 to 50 percent of fats and 7 to 13 percent of proteins. It also contains vitamins A, D and E. Soyabean oil contains 30 to 45 percent of proteins and 19 to 22 percent of fats. It also contains vitamin A and D apart from small amount of esters. Sunflower seeds make a nutritious food for cattle, poultry and cage birds.