目的 建立大孔树脂吸附梨果实中棒曲霉素的动力学模型.方法 以XDA-600型大孔树脂作为吸附剂吸附梨果汁中棒曲霉素,分析了吸附等温线、吸附热力学和动力学特征.结果 当温度为25 ℃时,XDA-600型大孔树脂对梨果汁中棒曲霉素具有良好的吸附效果.吸附热力学模型显示:大孔树脂对梨果汁中棒曲霉素的吸附符合Freundlich等温线模型(r2＞0.90),XDA-600型大孔树脂对梨果汁中棒曲霉素的吸附更符合准二级速率方程.结论 XDA-600型大孔树脂适合梨果汁中棒曲霉素的吸附.

The transesterification of fatty acid in maize germ oil deodorizer distillate with methanol catalyzed by immobilized lipase Novozym 435 and tert- butyl alcohol as solvent in the reaction system was studied. The optimal condition was fixed by single factor test. The results showed that the addition of lipase was 80 mg / g,reaction temperature 55 ℃,reaction time 20 h,the ratio of substances 1. 5∶ 1,the addition of tert- butyl alcohol 6%,then the esterification rate reached 96. 84%. The lipase was treated with acetone after each reaction and can be recycled 7 times without significant loss of activity.

采用水酶法可以提取玉米胚芽油.通过对玉米胚芽进行热处理抑制玉米胚芽中天然酶的活性,改变其结构进而提取高品质玉米胚芽油.利用酶对地产玉米进行处理,通过酶反应将玉米胚芽中的油脂释放,利用离心技术分离玉米胚芽油.采用此法获得的玉米胚芽油品质优良,其中游离脂肪酸含量为1.5％;总氧化物值8.1;微黄色,磷脂含量0.022％;生育酚含量1 350 mg/kg;氧化稳定性14.6 h.

Corn germ oil is a kind of high quality edible vegetable oil.With the increasing demand,the by-products after oil extraction are gradually increasing.In general,there are corn germ-residue,corn germ meal,defatted corn germ cake,oil foots and deodorization distillate.These by-products have broad prospects for comprehensive utilization in food industry,feed industry,pharmaceutical industry and chemical industry.

The technological conditions of aqueous enzymatic extraction of soluble dietary fiber from corn germ oil meal were discussed in this paper.By means of single-factor experiment and response surface methodology,the impacting factors that dietary fiber extraction ratio depended on amount of cellulose,timeand solid-liquid ratio,have been particularly studied.On the other hand,the technological parameters of extraction were optimized in detail.The results of experiments showed that,under the optimum conditions that the cellulose added of 13 Iu/g,solid-liquid ratio of 13∶ 1 and time of 3 hour,the extraction ratio of soluble dietary fiber was 6.65%,which was 49.01 percent of the total volume.

The article carried out a series of experiments about methyl esterification of fatty acid in deodorizer distillate,which was catalyzed by the strongly-acidic cationic exchange resin.The resins were selected,pretreated and dried.NKC-9 resin was chosen as the catalyst.The single factor is undertaken in order to get the optimal combination parameters.The process is optimized for the esterification of maize germ oil deodorizer distillate with methanol under following conditions:methanol:MGODD is 2∶ 1,catalyzed by NKC-9 resin at 60℃ for 5h.The results showed that strongly-acidic cationic exchange resin had perfect effect on catalyzing methyl esterification of fatty acid in deodorizer distillate;esterification rate was up to 97.8%.