【作者】 张敬尧；

【导师】 张东杰；

【作者基本信息】 黑龙江八一农垦大学 ， 食品科学， 2009， 硕士

【摘要】 大豆油含亚油酸50%～60%,油酸22% ~ 30%,棕榈酸7% ~ 10%,亚麻酸5% ~ 9%,硬脂酸2% ~ 5%,花生酸1% ~ 3%,脂肪酸构成较好,正是由于富含丰富的多不饱和脂肪酸,成品大豆油在流通过程中,由于储藏、运输、销售等环节控制不严,经常受到光、热、氧以及油脂中的水份和酶的影响,发生氧化酸败。因此,抑制油脂氧化、保持油脂新鲜程度并延长货架期最有效的方法是在食用油中添加抗氧化剂。本课题旨在寻找一种高效、天然、复合抗氧化剂以代替人工合成抗氧化剂应用于大豆油脂的抗氧化并以微胶囊包埋的形式添加到大豆油中以增强抗氧化剂的稳定性,提高油脂的食用品质和营养品质。实验以目前倍受人们青睐的三种天然食品抗氧化剂茶多酚、迷迭香及番茄红素为基础,将其两两复配并添加柠檬酸作为增效剂,通过考察贮藏期间油脂的过氧化值(POV)及硫代巴比妥酸值(TBA)的变化趋势,得出复合抗氧化剂茶多酚+迷迭香+柠檬酸具有显著的抗氧化性能,为优选的复合天然抗氧化剂,并通过正交试验得出其最佳配比为茶多酚:迷迭香:柠檬酸=4:7:5。且油脂氧化过程中其POV值与TBA值之间呈不完全正相关关系。采用喷雾干燥方法对优选的复合天然抗氧化剂进行微胶囊包埋以增强其稳定性和缓释性能。以麦芽糊精和辛烯基琥珀酸淀粉酯作为复合壁材制得的乳化液稳定性较好,微胶囊效率和产率较高。通过四元二次正交旋转实验,得出微胶囊抗氧化剂制备的最佳工艺参数为:固形物含量为24.69%,麦芽糊精与辛烯基琥珀酸淀粉钠的比例1:4.54,乳化剂添加量为7.18%,芯壁材体积比为1:6.85,在此条件下得到的微胶囊效率为80.976%。制得的微胶囊产品含水率为0.01%,密度为0.265 g/mL,溶解度为48%,平均粒径为30～100μm之间。用扫描电镜观察微胶囊产品的表面结构,可以看到微胶囊表面光滑无裂痕,基本呈球状,个别有小孔,有助于芯材物质的缓释。经过scall烘箱法加速氧化实验证明:微胶囊抗氧化剂在大豆油中的抗氧化效果要优于未被包埋的单体抗氧化剂,具有显著的抗氧化性能。将制得的微胶囊产品用于大豆油中进行缓慢释放,研究其释放规律。得到了抗氧化物质的累积释放曲线,并采用零级动力学模型、一级动力学模型、Higuchi、Peppas这几种模型分别对微胶囊体外释放进行模型拟合,结果表明:零级释放模型的R值为0.9828,方程拟合的绝对偏差和相对偏差较小,比较接近微胶囊的释放行为,释放机理是胶囊内囊心溶解扩散以及微胶囊骨架溶蚀协同作用的结果。更多还原

【Abstract】 Soybean oil contains 55% ~ 69% linoleic acid, 22% ~ 30% oleic acid, 7% ~ 10% palmitic acid, 2% ~ 5% stearic acid, and 1% ~ 3% arachidic acid. Soybean oil has a better fatty acid composition. It is rich in unsaturated fatty acid , soybean oil often has oxidative rancidity by the effect of light, heat, oxygen, water and enzyme in circulation process during storage, transportion and marketing. Therefore, the most effective way to inhibit oxidation and keep freshness and extend shelf life of edible oil is to adding anti-oxidants. The research aimed to seek an efficient, natural and compound antioxidant to replace synthetic antioxidants used in soybean oil. The compound antioxidant was added in the form of microcapsulation in order to enhance the stability of anti-oxidants and improve quality and nutrition.The research was based on three natural antioxidants , tea polyphenol, rosemary and lycopene. And adding the citric acid as a synergist to obtain an optimized compound by investigating the tends of POV value and TBA value during storage. The results showed that the optimized compound was TP +rosemary +citric acid which had significant antioxidant properties, and the best proportion of TP:rosemary:citric acid was 4:7:5 by orthogonal experiment. The POV value and TBA value didn’t have a positive correlation in the process of fat oxidation.The optimized compound antioxidants were microcapsulation by Spray Drying in order to enhance the stability and releasing ability. We can get a better emulsification stability and high MEE and MEY with maltodextrin and SSOS as compound wall materials. The optimized parameters that prepared microcapsulation were as follows: 24.69 % of solid content, maltodextrin and SSOS is the ratio of 1 to 4.54, 7.18 % of emulsifier content and core and wall material is the ratio of 1 to 6.85. The maximun microcapsulation efficiency is 80.41% at the above conditions.The water content of microcapsulation was 0.01%, and the density was 0.265g·mL-1 , and the solubility was 48% , and the average diameter of capsule particle was between 30 to 100μm .The surface structure was observed by SEM. We can see that the surface was smooth, no one cracked and basically spherical, but individuals had ascopore which will help slowly-releasing. The accelerated oxidation tests confirmed that the microcapsulation have significant antioxidant properties, and much better than that of compound .Get the microcapsulation products slowly releasing in the soybean oil to study the laws of slowly releasing and obtain its releasing curve. The microcapsulation releasing model was fitted by first class, zero class, Higuchi and Peppas releasing model. The results indicated that zero class was much closer to the releasing behavior of microcapsulation, and had the less absolute deviation and relative deviation of fitting equation, and the maximal correlation coefficient was 0.9828. The releasing mechanism was solution and diffusion of the microcapsulation heart as well as corrosion of capsule skeleton.更多还原