EXTRACTION OF OIL FROM LOCAL SEEDS

Abstract

Groundnut oil is also known as peanut oil or Arachis oil, is a mild-tasting vegetable oil expressed from groundnut kernels. Groundnut oil is generally used in cooking, including frying, basting, and the manufacture of margarine and shortenings. Groundnut oil is light yellow transparent edible oil with clear color and lecture, pleasant fragrance and good taste is relatively easy to digest. Groundnuts or peanuts are a popular source of food throughout the world. And the groundnut oil, however, can be used for cooking, they can be used as a shortening or as a base for confectioneries and they can be used to make peanut butter. Groundnut kernel contains 45 to 55% of oil. The Groundnut oil obtained from the kernel is yellow to greenish-yellow in color. The meal is a very important component of feeds for poultry and cattle. Groundnut oil is an organic material oil that derived from peanuts, noted to have the aroma and taste of its parent legume. Peanuts or Groundnut oils can be extracted in various ways. Always method used depends on the oil. India is the second-largest producer of peanuts after China. Groundnut or Peanut is the largest oilseed in India in terms of production. It accounted for about 35.99 percent of the oilseeds production of the country during 2007-08. Generally, 2.5 kg of groundnut to produce 1 liter of the groundnut oil. The cost of procurement and processing of the groundnut or peanut is around Rs. 90/kg. Hence, simple math says that Rs. 225/liter is the raw material cost. In India groundnut or peanut is grown over an area of 6.9 million hectares with a total production of 5.3 million tones. Groundnut cultivation is mainly confined to south Indian states, viz, Gujarat, Andra Pradesh, Karnataka, Tamil Nadu, and Maharashtra. The other important states grown Groundnut are Madhya Pradesh, Rajasthan, Uttar Pradesh, and Punjab .From harvested groundnuts to pure edible peanut oil or groundnut oil production is a complex process. The main procedure is groundnuts preprocessing, pre-pressing, solvent extraction, crude peanut oil refining. The Groundnuts must be pre-processed before sending to the expelling department, the kernels need to be cleaned, shelled, cracked and cooked by special seed processing machinery. Then the prepared peanut kernels will be transported to the prepressing workshop in where these raw materials could be first expelled by screw oil press machines. However, the screwing process of pressing is a high residual oil rate. In this time, the chemical method solvent extraction will be a good method to fully extract peanut oils. The solvent extraction method can create the residual oil rate of the groundnut meal below 1%. Therefore, for edible use, the pressed crude groundnut oil needs to be refined by filte r presses or oil refining plant.