Quantitative changes in some unsaponifiable components of soya bean oil due to refining

Abstract

The effects were studied of the processes of degumming, neutralisation, bleaching and deodorisation on the content and composition of the various fractions of unsaponifiables in soya bean oil. The effect of each of the various technological steps on the decrement of the investigated unsaponifiables in the processed oils was different. When compared with the crude oil, the refined soya bean oil contained less tocopherols (by 31 to 47'4, sterols (by 25 to 32%) and squalene (by 15 to 37%). No significant differences were observed in the compositions of the sterol and tocopherol fractions of the crude and refined soya bean oils.

Effect of chemical refining steps on the minor and major components of cottonseed oil

“…This could be explained that during industrial processing of oils and fats, phytosterols undergo dehydration, resulting in the formation of sterenes. Sterenes are formed during bleaching due to acid catalyzed, dehydration on the surface of the acid-activated bleaching earth or due to dehydration promoted by heat during the deodorization process (Grob et al, 1992;Ferraei et al, 1996).During neutralization, the phytosterols are transferred by liquid-liquid partitioning to soapstock (Gutfinger and Letan, 1974;Serani and Piacenti, 1992;Sciancalepore, 1981;Karaali, 1985;Karabulut et al, 2005), however bleaching affects phytosterols through the nonpolar dehydration i.e. sterenes were formed due to acid-catalyzed dehydration on the surface of the acid -activated bleaching earth as well as dehydration promoted by heat during deodorization step (Ferraei et al, 1989;Grob et al, 1992;EL-Shami et al, 1994, Ferraei et al, 1996.…”

“…Dehydration also occurs which results in the formation of stearadienes (Leone, et al, 1984;Ferraei, et al, 1989;Zunin, et al, 1989;Grob, et al, 1992;Ferraei, et al, 1997). During neutralization, in chemical refining, large parts of the phytosterols (9-21 %) are transferred by liquid-liquid partitioning to the soapstock (Gutfinger and Letan, 1974;Sciancalepore, 1981;Karaali, 1985). In addition, bleaching and especially high temperature steam refining or deodorization removes a portion of the sterols (Karabulut, et al, 2005; Ubhayaekera and Dutte 2009).…”

“…In addition, bleaching and especially high temperature steam refining or deodorization removes a portion of the sterols (Karabulut, et al, 2005; Ubhayaekera and Dutte 2009). Actually, the deodorized distillate is a good source of tocopherols and phytosterols (Gutfinger andLetan, 1974, Homberg andBielefeld, 1982;Verleyen, et al, 2001). …”

Effects of refining process on sunflower oil minor components: a review

“…A significant decline in the total sterol content in vegetable oil has been reported during the chemical neutralization step (Gutfinger and Letan, 1974), which is attributed to a liquid-liquid partitioning of phytosterols into the soapstock (Serani and Piacenti, 1992 (Alpaslan et al, 2001;Ergönül and Köseoǧlu, 2014;Karaali, 1985;Kreps et al, 2014;Nergiz and Çelikkale, 2011;Talal et al, 2013;Tasan and Demirci, 2005;Verleyen, Forcades et al, 2002).…”

Extraction and Enzymatic Modification of Functional Lipids from Soybean Oil Deodorizer Distillate

“…Phytosterols are progressively lost during refining while continuously altering the ratio of free and esterified sterols (Kochhar, 1983). During chemical neutralization, the free sterol content is significantly reduced especially upon addition of weak caustic solution due to the loss in the soapstock (Gutfinger & Letan, 1974). Bleaching effects on phytosterols are generally minor and mainly limited to the formation of some nonpolar dehydration products (Ferrari, 1996) and partial hydrolysis of sterol esters (Homberg & Bielefeld, 1982).…”