【作者】 刘鹏飞；

【导师】 董海洲；

【作者基本信息】 山东农业大学 ， 农产品加工及贮藏工程， 2011， 硕士

【摘要】 随着人们对食品品质和保藏期要求的不断提高,以及人们环保意识的增强,以天然生物材料制成的可食膜在食品包装领域正成为研究的热点。而传统的溶液流延法制备可食性包装膜,由于生产效率低,已不能满足工业化生产的需求。本文采用熔融共混挤出技术制备热塑性淀粉,再经挤出流延法制备淀粉基可食性包装材料。主要试验结果如下:1.适宜的成膜基材和胶粘剂为氧化酯化淀粉、普鲁兰多糖。2.添加甘油后有效的改善了热塑性淀粉的流动性。随着甘油添加量的增加,淀粉膜的抗拉强度和水溶解时间逐渐减小,而断裂伸长率、氧气透过量、透光率和水蒸气透过量逐渐增大。当甘油用量<31%时,膜较脆,拉伸性能差;当甘油用量>31%时,膜较软,且抗张强度也较低。综合膜的各项性能得出,甘油的适宜添加量为31%。3.添加普鲁兰多糖后有效的改善了淀粉膜的拉伸性能。随着普鲁兰多糖添加量的增加,淀粉膜的水溶解时间和氧气透过率逐渐降低。当普鲁兰多糖添加量在5%～9%时,淀粉膜具有相对较低的透湿性,且淀粉膜的白度较高,黄色值较低。光学显微分析膜表面,当普鲁兰多糖添加量为9%时,普鲁兰多糖与淀粉能较好的融合。综合膜的各项性能得出,普鲁兰多糖的添加量不宜超过9%。4.添加硬脂酸后有效的改善了热塑性淀粉的流动性和膜的耐水性。随着硬脂酸添加量的增加,淀粉膜的抗拉强度和水溶解时间逐渐增大,而断裂伸长率和水蒸气透过量逐渐降低;当硬脂酸添加量超过1.6%后,膜材的脆性逐渐增大,白度降低,黄色值增加。综合膜的各项性能得出,硬脂酸的添加量不宜超过1.6%。5.膜的应用性实验结果表明:本实验制备的淀粉膜具有较好的包装性能、降解性能及氧气阻隔性能,可用于对氧气敏感的多种食品的内包装。更多还原

【Abstract】 With preservation of food quality and continuous improvement of the requirements, as well as increased awareness of environmental protection, natural biological materials made of edible films in food packaging become a hot research field. The traditional solution cast film prepared edible packaging could not satisfy the needs of industrial production, due to the lower production efficiency. In this article, the thermoplastic starch was prepared by the method of melt mixture extrusion, and then prepared by extrusion casting edible starch-based packaging materials. The main results were as follows:1. The suitable film substrate was the oxidative esterification of starch and the suitable adhesive was the pullulan.2. The mobility of the thermoplastic starch was improved effectively by adding glycerol. With the addition of glycerol increased, the water dissolution time and tensile strength gradually decreased, while the elongation/ oxygen transmission rate/ transmittance/ water vapor permeability gradually increased. When the glycerol content<31%, the film was brittle and its tensile properties was poor; when the glycerol content>31%, the film was softer and its tensile strength was lower. The conclusion was: for the best properties of the starch film, the suitable addition amount of glycerol was 31%.3. The tensile strength of the starch film was improved effectively by adding pullulan. With the addition of pullulan increased, the water dissolution time and oxygen permeability gradually decreased. Lower water vapor permeability, higher whiteness value and lower yellowness value were obtained with the addition of pollution in the range of 5%～9%. The optical microscopy analysis of the film surface suggested that the pullulan and the starch can be fused better by the addition of pullulan with 9%.The conclusion was: for the best properties of the starch film, the addition of pullulan was better with no more than 9%.4. The mobility of the thermoplastic starch and the water resistance of the films were improved effectively by adding stearic acid. With the addition of stearic acid increased, the water dissolution time and tensile strength gradually increased, while the elongation and water vapor permeability gradually decreased. When the stearic acid content>1.6%, the fragility of the starch film gradually increased, the L color values decreased and the b color values increased. The conclusion was: for the best properties of the starch film, the addition of stearic acid was better with no more than 1.6%.5. The application of films results showed that: the starch film got better packaging properties, degradation properties and oxygen barrier properties. It could be used in oxygen-sensitive food packaging.更多还原