Using Two-step Enzymic Method Catalyzes Camphor Seed Kernel Oil To Compose Structured Lipid And Purification The Products

Obesity has become a global problem with high-fat,high-calorie foods over intaken.Therefore,finding a fat substitute which not only can ensure the oil's functionality,but also is quickly consumed,has become a hot topic.To achieve this purpose,reconstruct the functional structure of the natural oil is an effective means.Structured lipids is a kind of lipid that has a specific molecular structure and physiological functions or special nutritional properties after reconstruct the composition and location of the fatty acid on natural lipid.In this article,the camphor tree seed kernel oil was used as raw material,which was riched in medium chain fatty acids,using the two-step enzymateic method to put a long chain fatty acids--Oleic acid into the camphor tree seed kernel oil's molecular structure,a special Structured lipids with the medium chain fatty acid on the Sn-2 of its glycerin skeleton was prepared.Single factor and orthogonal experiments were employed to optimize the experiment.The products obtained by two-step enzymeic method was purified by two-step molecular distillation and column chromatography,the fatty acid composition and distribution of the product was analysed by GC,and the composition of the triglyceride was analysed by HPLC,the Physical and chemical properties of the product was determined by GB methods.The main research results were as follows:(1)Single factor experiment were employed to optimize the effect of the substrate molar ratio,enzyme load,reaction temperature and reaction time on alcoholysis reaction.On this basis,orthogonal experiment was designed to optimize synthesis process of alcoholysis reaction.And the optimum alcoholysis process conditions was as follows:the molar ratio of camphor tree seed kernel oil to nhydrous ethanol 1:4,the amount of lipase 8%(w/w of substrates),the reaction was carried out at 40? for 24h,the average content of MAGs was 38.82%.The product of alcoholysis reaction was purified by two-step molecular distillation,and the best condition was as follows:the feed materiel quantity was 3.5mL/min,distillation temperature was 130?,Condensing surface temperature was 55 ?,pressure was below 1 Pa.(2)Single factor experiment was used to study the substrate molar ratio,enzyme load,add water,reaction temperature and reaction time on esterification reaction.On this basis,orthogonal experiment was designed to optimize synthesis process of esterification reaction.And the optimum esterification process conditions was:the molar ratio of MAGs to Oleic acid 1:4,the amount of lipase 10%(w/w of substrates),the reaction was carried out at 45 ? for 16h,the average content of structured lipids was 60.48%.The product of esterification reaction was purified by column chromatography.(3)Physicochemical properties of the transesterification product were as follows:peroxide value was 0.0635 meq/Kg,iodine value was 10.15 gI2/100g,acid value was 0.8917 mgKOH/g,saponification value was 257.53mg KOH/Kg,and Melting point was 17±1?.(4)The configuration of the structured lipids:OLaO and OCO(C?La?O represent capric acid,lauric acid and oleic acid)was analysed by HPLC-ELSD.