Refining high-free fatty acid wheat germ oil

Wheat germ oil was refined using conventional degumming, neutralization, bleaching and continuous tray deodorization, and the effects of processing conditions on oil quality wore determined. The crude wheat germ oil contained 1,428 ppm phosphorus, 15.7% free fatty acid (FFA), and 2,682 ppm total tocopherol, and had a peroxide value (PV) of 20 meq/kg. Degumming did not appreciably reduce the phosphorus content, whereas neutralization was Effective in removing phospholipid. Total tocopherol content did not significantly change during degumming, neutralization, and bleaching. A factorial experimental design of three deodorization temperatures and three residence times (oil flow rates) was used to determine quality changes during deodorization. High temperatures and long residence times in deodorization produced oils with less FFA, TV, and red color. Deodorization at temperatures up to 250 degreesC for up to 9 min did not significantly reduce tocopherol content, but, at 290 degreesC for 30-min residence time, the tocopherol content was significantly reduced. Good-quality wheat germ oil was produced after modifying standard oil refining procedures.