Fractionation Of Tea Seed Oil And Interesteriifcation With Its’Stearin Fraction

In this paper, the time of zero freezing test of the tea oil was improved by dryfractionation. The fractionation factors of refined tea oil and raw tea oil were investigated andthe effect of tea oil quality on fractionation was also discussed. And margarine stock can beprepared using chemical interesterification product of the fraction stearin and palm stearin.Tea oil riched in many physiological contents, which were widely used in edible oil,cosmetic, and medicine. When tea oil was placed in lower tempreture, flocculentcrystallization would be appeared. While traditional fractionation process of tea oil wascontrolled by crystallization rate or addition of help crystallization agent such as diatomite ortalcum powder. But these traditional methods need long time, and the fractionation effect wasnot well. This problem can be resolved by dry fractinonation of refined tea oil, which canimprove the freezing resistance using the addition of homemade crystallization seed. Theoptimum time of zero freezing test of refining tea oil was406h under the conditions of-0.33℃,19h, and0.31%(relative to weight of reefing tea oil) addition load of homemadecrystallization seed. The optimum time of zero freezing test of crude tea oil was601h underthe conditions of-1.6℃,19h, and0.14%(relative to weight of crude tea oil) addition load ofhomemade crystallization seed.Stearin fractions of refining tea oil were interesterification with palm stearin underdifferent ratio by sodium methoxide to prepare margarine and shortening stock oil. The ratiosof tea oil strarin and palm stearin were70:30,65:35,60:40,55:45and50:50(w/w). Sn-2FAcomposition of product was investigated, which showed that the change of sn-2FAcomposition was accorded with random interesterification. After interesterification, meltingpoint of product dropped12.3-13.5℃. These results combined SFC showed thatinteresterification oil was more suitable for margarine using. Under the ratio of60:40, theinteresterification factors were investigated. The result of single factor experiments showedthe optimum conditions were as follows: dosage of sodium methoxide0.5%, reactiontemperature80℃, and reaction time30min. Based on the single factor experiments, responsesurface method was used to optimize interesterification reaction. The quadratic regressionmodel was established, and in this model the expected value was well fitted with the actualvalue. The optimum reaction conditions were as follows:(1) dosage of sodium methoxide 0.5%, reaction temperature96℃, and reaction time22min; under these conditions, thepalmitic acid content of sn-2of interesterified oil was36.49%, and it completed the randominteresterification.(2) dosage of sodium methoxide0.65%, reaction temperature73℃, andreaction time31min; under these conditions, the palmitic acid content of sn-2ofinteresterified oil was37.24%，and it completed the random interesterification。...