生物酶保鲜纸的研究与开发

发布时间：2018-03-28 02:14

  本文选题：生物酶保鲜纸　切入点：固定化葡萄糖氧化酶　出处：《浙江理工大学》2017年硕士论文

【摘要】：杨梅是我国的特色水果,果实成熟时期高温多雨,且无外果皮包裹,人们常说,杨梅“头日采收,二日色变,三日味变”,由此可见其变质速度之快。杨梅的贮藏与运输问题是限制杨梅产业发展的瓶颈,因此,研究杨梅的保鲜技术,延长杨梅的保鲜时间具有十分重要的意义。本文利用葡萄糖氧化酶(GOD)制备具有除氧作用的生物酶保鲜纸对杨梅进行保鲜,首先对GOD的固定化,优选载体及优化工艺条件后,制备固定化GOD;然后将固定化GOD与糊化阴离子淀粉混合制备成杨梅保鲜涂料,再将制备的涂料涂布在食品包装纸表面,自然风干得到生物酶保鲜纸;最后研究了生物酶保鲜纸的物理性能、除氧性能以及在杨梅保鲜上的应用。首先,得出固定化GOD的最佳载体是比表面积为300m~2/g的气相法SiO_2;最佳工艺条件为:反应温度30℃,pH值5.1,加酶量0.5mg,戊二醛浓度0.10%,交联时间3h,该条件下固定化效果最好,固定化GOD的酶活力回收率达到75%;GOD经固定化后,分散稳定性得到明显提高,贮藏稳定性相对于游离的GOD也有较明显的提高,在贮藏60d后,固定化GOD活性仍保持原酶活力的90%以上,而游离GOD活性降低至原酶活性的70%;经FT-IR分析可知,固定化GOD的红外光谱中,在1637cm~(-1)、1110cm~(-1)、1540cm~(-1)处出现特征峰,其中1637cm~(-1)处出现的C=N伸缩振动峰主要是因为形成Schiff碱所导致,说明GOD被固定在气相法SiO_2载体上,且酶蛋白的二级结构没有发生改变。然后,研究了生物酶保鲜纸的制备技术,得到生物酶保鲜纸涂料配方:固定化GOD用量为6g、蒸馏水74g以及15%阴离子淀粉32g混合配制成涂料,得到涂料的固含量为9.6%。随着杨梅保鲜涂布量的增加,保鲜纸除氧效果逐渐增强,当涂布量为8g/m~2,固定化GOD的含量为4.4g/m~2时,常温(25℃)条件下,250min内氧气含量降低了56%,除氧效果显著。最后,用涂布量为8g/m~2生物酶保鲜纸对杨梅进行保鲜研究,通过空白对照实验表明,利用生物酶保鲜纸对杨梅进行保鲜,其贮藏环境中的氧气含量和乙烯产生量明显减少;通过对杨梅生理变化的研究表明,使用生物酶保鲜纸对杨梅进行保鲜,杨梅贮藏到第4d才开始腐烂变质,贮藏6d后,其好果率是未使用生物酶保鲜纸的2倍以上,有效的延长了杨梅的保鲜期。
[Abstract]:Bayberry is a characteristic fruit of our country. It is hot and rainy in ripening period, and there is no outer pericarp wrapped in it. People often say that bayberry is "harvested in the first day and changed in color in two days." It can be seen that the speed of deterioration is so fast. The storage and transportation of bayberry is the bottleneck restricting the development of bayberry industry. Therefore, research on the preservation technology of bayberry, It is of great significance to prolong the preservation time of Myrica rubra. In this paper, the biological enzyme paper with deoxygenation effect was prepared by using glucose oxidase oxidase to keep myrica rubra fresh. Firstly, the immobilization of GOD, the selection of carrier and the optimization of technological conditions were carried out. Then the immobilized GOD and gelatinized anion starch were mixed to prepare the preservative coating of Myrica rubra, and then the coating was coated on the surface of the food packaging paper, and the bio-enzyme preservation paper was obtained by natural air drying. Finally, the physical properties, deoxygenation and application in the preservation of Myrica rubra were studied. The best carrier for immobilized GOD was the gas phase method SiOs _ 2 with specific surface area of 300m~2/g. The optimum conditions were as follows: reaction temperature 30 鈩，

本文编号：1674298