(1) HMFS enriched with sn-2 PA content was firstly produced catalyzed by Lipozyme RM IM, using the extraction of FFAs of mixed oils (olive oil, coconut oil and microalgae oil) and tripalmitin (PPP) as the substrates for the transesterification reaction。 The mixture of rich in monounsaturated fatty acids of olive oil, coconut oil enriched with short carbon chain and DHA-riched algae oil was prepared into acyl donor according to the corresponding proportion to enzymatic synthesis of HMFS。 The results indicated that the content of PA at the sn-2 position increased to 70。11±2。71%。 The optimal conditions were obtained as followed: substrate molar ratio (FFAs: PPP) of 9: 1, temperature: 70 oC, lipase load: 10%, reaction time: 3 h。
(2) HMFS was produced from mixed oils and PPP by enzymatic transesterification, in a microwave reactor。 The results indicated that under the optimal condition (i。e。, lipase load: 10%, molar ratio of FFAs to PPP: 7:1, water activity: 0。75), the total content of the PA in the triacylglycerols (TAGs) decreased from 36。31±0。59% to 33。31±0。50%。 Compared with a batch reactor, the optimum reaction temperature decreased from 70 oC to 50 oC, the reaction time was significantly shortened from 3 h to 1 h, and the content of PA at the sn-2 position increased from 70。11±2。71% to 81。31±2。82%, the lipase could be reused at least 34 times without losing catalytic activity。
(3) The purification and characterization of HMFS enriched PA at sn-2 position from were analysed。 After freezing crystallization, the variety of melting and crystallization of HMFS were enlarged with differential scanning calorimeter (DSC) respectively, which showed that HMFS is easier to be absorbed by human body, and the transesterification improved the character of oil。
(4) The method of ferulic acid modified the triglycerides in a batch reactor was built。 The results indicated that under the optimal condition (i。e。, catalyst amounts: 10%, molar ratio of ferulic acid/glycerol: 25, temperature: 80 oC, reaction time: 10 h), the converison of ferulic acid achieve 89。69±0。60%。
(5) The method of ferulic acid modified the triglycerides was built, in a microwave reactor。 The results indicated that under the optimal condition (i。e。, substrate ratio: 25:1, catalyst amounts: 8%, temperature: 65 oC, microwave: 100 W of power, reaction time: 5 h), the converison of ferulic acid achieve the optimal effect (89。58±0。74%)。 Compared with a batch reactor, the optimum reaction temperature decreased from 80 oC to 65 oC, the reaction time was significantly shortened by 1/2。
In conclusion, from mixed oils to produce high value-added HMFS enriched sn-2 PA by enzymatic interesterification may be beneficial to digestion and absorption for infant。 In addition, TAGs was modified by ferulic acid, which strengthened its antioxidant properties, which has distinct advantages and potential applications。
Keywords: Microwave strengthening; Human milk fat substitutes; Transesterification; Ferulic acid。
目 录
第一章 绪论 1
1。1微波强化酶催化反应 1
1。1。1微波概述 1
1。1。2微波在酶促反应中的应用 1
1。1。3微波强化合成的应用前景 2
1。2苯丙酸的概述 3
1。2。1苯丙酸的结构和种类 3
1。2。2阿魏酸的应用 3
1。3母乳脂肪替代品 4
1。3。1母乳脂肪替代品的结构和功能 4
1。3。2原材料的选择 微波强化酶催化苯丙酸修饰蚕蛹油合成新型母乳脂肪替代品(2):http://www.youerw.com/shengwu/lunwen_116814.html