REVIEW OF RICE BRAN WAX EXTRACTION AND REFINING PROCESS

Sonal Kapur* and Deepak Wasule

ABSTRACT

Rice bran wax (RBW) is a valuable by-product obtained during the refining of rice bran oil which contains approximately 2-5% wax before refining, which makes it one of the oils with the highest wax content. Crude bran wax contains a significant amount of oil (up to 60%), and small amounts of impurities, water, gums, resinous matter, free fatty acid, and phospholipids. The presence of these impurities affects the color and performance of the product. Refining crude wax is necessary for its use in the industry. The wax extraction is accomplished by mechanical and chemical processes during the dewaxing of oil. It can be separated from oil by tank settling, winterization, batch chromatography, etc. Refining crude rice bran wax typically involves defatting, bleaching, filtration, and deodorization to ensure the high purity and quality of the resultant wax. Defatting can remove about 90% of the oil from the crude wax in the first extraction and up to 98% in subsequent extractions. Refining of crude rice bran wax is crucial in removing impurities such as free fatty acids, resinous matter, residual oil, and smell, only after which it can be used in food, cosmetics, and pharmaceutical industries. The crude wax can be used as such in products like shoe polishes where odor and color are of no great importance.

Keywords: Rice bran wax, uses, extraction, refining.