【作者】 刘洪洪；

【导师】 石彦国； 张毅方；

【作者基本信息】 哈尔滨商业大学 ， 农产品加工与贮藏工程， 2010， 硕士

【摘要】 大豆分离蛋白被广泛应用于食品工业,但在贮运过程中其功能特性可能会发生变化。本研究采用不同包装形式(100%氮气铝箔包装、80%氮气：20%二氧化碳铝箔包装、60%氮气：40%二氧化碳铝箔包装、真空铝箔包装、实际工厂包装：白板纸塑/HDPE和PE包装)将大豆分离蛋白(SPI)包装后分别在高温高湿环境(RH 80%、30℃),常温常湿环境(RH 65%、25℃),低温条件(4℃),冷冻条件(-20℃～-18℃)和自然环境条件下储藏5个月。研究储藏环境、时间、包装条件对SPI功能特性(包括溶解性、乳化性及乳化稳定性、吸油性、吸水性和胶凝性)的影响。只有在高温高湿环境下储藏至第四个月的PE包装中SPI的7S/11S比值与对照样相比显著下降(p<0.05),并且SPI亚基有不同程度的缺失,以PE包装中SPI亚基缺失明显；其余储藏条件下SPI的7S/11S比值变化不显著。但是通过SDS-PAGE实验发现SPI在所有储藏条件下都发生了亚基的解离和大分子物质的聚集。通过研究SPI巯基和二硫键变化情况,发现在储藏过程中,SPI巯基含量下降、二硫键含量上升；并且充气包装和真空包装中SPI的巯基含量下降幅度小,二硫键含量上升幅度小；PE包装中SPI的巯基含量下降快,二硫键含量上升快。温度越低SPI巯基含量下降幅度越小,二硫键含量上升越快(但是冷冻环境下SPI二硫键上升速度小于低温环境)。在高温高湿环境、常温常湿环境、自然环境下短期储藏时,充气包装中的氮气能够使SPI的溶解性、乳化性及乳化稳定性和胶凝性迅速增加,延缓SPI吸水性下降；随储藏时间的延长,氮气比例越低,温湿度越低,SPI功能特性相对保持较好。通过对各包装中SPI功能特性的比较得出包装材质对温湿度的阻隔性：铝箔包装>工厂包装>PE。低温和冷冻环境能够使SPI的溶解性、乳化性及乳化稳定性和胶凝性增加,延缓SPI吸水性下降,其中以PE包装中SPI的溶解性、乳化性和胶凝性上升幅度最大,但随储藏时间延长SPI的功能特性仍下降,其中以60%N2：40%CO2充气铝箔包装能够使SPI保持相对较好的功能特性。氮气能够使SPI的吸油性显著上升,上升后不随储藏时间(5个月),环境温湿度、充气比例的变化而变化。除高温高湿环境下,PE包装中SPI的吸油性在储藏3个月后显著下降外,其余四种储藏环境下SPI的吸油性与包装材质、储藏时间(5个月)、环境温湿度无明显关联。通过相关性分析得出,只有在高温高湿环境下,PE包装中SPI的7S/11S比值与吸油性呈极显著的正相关,与溶解性、乳化性及乳化稳定性、吸水性、凝胶性相关性不显著；在五种环境下储藏时,PE包装中SPI巯基含量的变化均与乳化稳定性、吸水性均呈极显著的正相关；二硫键含量的变化均与乳化稳定性、吸水性均呈极显著的负相关。60%N2：40%C02充气铝箔包装中SPI巯基含量的变化均与吸水性呈显著的正相关,与吸油性呈显著的负相关；二硫键含量的变化均与吸水性呈显著的负相关,与吸油性呈显著的正相关。更多还原

【Abstract】 The SPI was applied in food industry widely, but the functionalities of it may change during storage. The effect of store temperature, time, RH and package material on SPI functionalities such as solution, emulsification, oil absorption, water absorption and gelation property were studied, when SPI was packaged in 100% N2 and Al,80%N2:20%CO2 and Al, 60%N2:40% CO2 and Al, vacuum and Al, white paper/plastic/HDPE, and PE and then stored for 5 months in the conditions of RH 80%、30℃, RH 65%、25℃,4℃,-20℃～-18℃and naturally.It was shown that the 7S/11S of SPI only packaged in PE and stored in high temperature and RH for 4 months decreased significantly(p<0.05), while the subunit of SPI would lost in different levels and obviously in PE. It was observed by SDS-PAGE that in all storage, the subunit of SPI disaggregated and molecules aggregated.Focus on the sulfhydryln group and disulfide bond, it was found that the content of sulfydryl decreases while disulfide bond increased. They both changed slightly in inflatable and vacuum packaging but sharp in PE packaging. The lower was the temperature, the slighter decreased the content of-SH and sharper increased the-S-S-. The content of-S-S-increased slower in the freezing condition than in the cool temperature.The N2 in the inflatable packaging could enhance the solubility, emulsibility and gelation property of SPI rapidly and delay the decreasing of water absorption in the condition of high, ambient temperature and RH and natural with short storage. In the storage, the lower was the N2 percent and the temperature and RH, the more stable was the functionalities. Comparing the functionalities of SPI with different packaging material, it was shown that the sequence of the barrier property of material to T and RH was Al packaging>factory packaging>PE packaging.The solubility, emulsibility and gelation property of SPI improved in the cool and frozen condition. The decreasing of water absorption was delayed. The functionalities of SPI with PE packaging enhanced obviously. But with the time going, they decreased, except for the SPI in 60%N2:40%CO2 and Al packaging.It has been showed that N2 could improve the oil absorption of SPI significantly and then keep it stable even as the time, ambient temperature and RH, content etc.. The oil absorption of SPI with PE packaging and 3 months storage of high temperature and RH decreased significantly, and other four storage conditions, packaging material and ambient condition had little relationship with it.Analysis by relatedness, it was shown that the 7S/11S of SPI with PE packaging storage only in high T and RH was significantly positive correlation with oil absorption, but not with solution, emulsification, water property and gelation property. In the five storage pattern, the content of-SH with PE was significantly positive correlation with emulsion stability and water absorption, but the content of-S-S-was significantly negative correlation with them. The-SH of SPI in 60%N2:40%CO2 inflatable Al packaging was significantly positive correlation with water absorption and negative correlation with oil absorption, the-S-S-was negative correlation with water absorption but positive with oil absorption.更多还原