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Dingsheng Machine provides chemical solvent extraction technology process for rice bran oil

Date:Dec 23rd, 2022
Dingsheng Machine provide a full set of advanced rice bran oil processing equipment and  rice bran oil manufacturing processes, which include raw material preparation technology, chemical solvents extraction technology, crude oil refining technology.

Rice bran is by-product obtained during rice milling operation. This is golden reddish cuticle obtained after removal of the husk and during polishing of the rice. Rice bran is the very thin layer of brown rice and most nutritious part. It is bestowed with high amounts of vitamins and minerals. Rice bran oil is also used in cosmetics because of its moisturising properties. Rich in vitamin E, it flows smoothly and penetrates well and does not stick on to the skin. It is greatly valued as an excellent carrier oil. Rice bran oil is manufactured from the inner husk and germ of brown rice. It has a mild nutty and neutral taste and stable when exposed to high temperature.

The crude rice bran oil is extracted either by mechanical method with oil presser or by chemical method with solvent extraction. Rice bran oil is extracted by chemical solvent process or pressed directly from rice bran. There are several techniques used to extract RBO, but solvent extraction using hexane is the most widely used conventional method for commercial extraction. For a minimal amount of oil extraction expelling pressing method can be used while large scale manufacturing uses solvent making technique. Hot extraction process gets more oil yield and pure edible oil than the cold processing.

The three main steps involved in rice bran oil extraction include: Raw material preparation – Rice bran oil extraction- Crude oil refining

Raw Material Preparation Process  
Rice bran is initially screened, graded and sorted which are then heated at a temperature higher than 100 C by steam to prevent lipase hydrolysis reaction in rice bran before the extraction process.

Rice Bran Oil Extraction Process  
The crude rice bran oil is extracted either by mechanical method with oil presser or by chemical method with solvent extraction. The rice bran is completely stabilized where oil is removed producing two products a high-quality crude rice bran oil and defatted rice bran.

Cold Pressed Extraction Process  
The cold pressed RBO is produced by compressing the rice bran through a mechanical screw press under mild heating (<50 °C), and the resulting oil is then filtered through filter paper, to produce the refined functional oil. Defatted rice bran and filter cake are the main by-products from this process.

Chemical Solvent Extraction Process  
RBO produced from solvent (normally hexane) extraction is preferred as a cooking oil, after further refinement, while the oil produced by cold pressed extraction is considered to be a superior functional oil as a dietary supplement and medicinal purposes. After solvent extraction, further refining of the rice bran oil involves degumming, neutralization, bleaching, dewaxing, and deodorizing to produce quality cooking oil, resulting in large amount of waste products left from the processes. Degumming involves the removal of phospholipids and lipoproteins through hydration by water with citric or phosphoric acid. Free fatty acids (FFAs) are removed by caustic soda (NaOH) in the neutralization process. Rice acid oil

(RAO) is the major waste product from these two steps. Then, the bleaching step is applied to remove the pigments (including chlorophylls and carotenoids) of the RBO by adsorption on activated carbon or bleaching earth. A dewaxing and winterization steps follow by maintaining the oil at a low and very low temperature respectively to cause the solidified waxes and other high melting point substances as well as high melting point wax are separated as waste products.

Rice Bran Oil Refining Process  
The crude rice bran oil obtained is further processed to remove the free fatty acids and offers an oil with less processing suitable for agricultural purposes. Edible oil which is bleached leaves mild flavour and smell and it must be removed by steam distillation before final packaging.

Steam Distillation Process  
This is the final step in the process of extracting edible oil where residual free fatty acids and any undesirable flavours are removed from the oil. The fully processed oil is ready for packaging into retail bottles, food service pails or large storage container.

Dingsheng Machine is committed to optimizing technology processes, reuse processing by-products while increasing annual output, help rice bran oil mill achieve higher processing capacity and improve their products quality and profit. When you plan to build a rice bran oil processing plant, please contact us today to get the quote.

For more information please contact:
Justin (Sales Manager)
Email:company@dingmachinery.com
Whatsapp: +86-137 0392 6330




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