银杏柠檬酸淀粉酯的制备及加工特性研究

Preparation and processing characteristics of ginkgo citrate starch ester

银杏种仁的主要营养成分是淀粉。以银杏淀粉为原料,柠檬酸为酯化剂制备银杏柠檬酸淀粉酯,考察柠檬酸添加量、pH、反应温度、反应时间对柠檬酸淀粉酯取代度(DS)的影响,通过正交试验确定了银杏柠檬酸淀粉酯的最佳制备工艺,并分析比较了银杏淀粉和银杏柠檬酸淀粉酯的透明度、膨胀率、溶解度、持水率等加工特性。结果表明:柠檬酸添加量和pH对DS的影响显著(p<0.05),反应温度对DS的影响不显著(p>0.05)。银杏柠檬酸淀粉酯的最佳制备工艺为:柠檬酸添加量8mL,pH2.0,反应温度132℃,反应时间6.0h。在此条件下制备得到的银杏柠檬酸淀粉酯平均取代度DS为0.355。银杏柠檬酸淀粉酯的透光率、溶解度、持水率和膨胀率分别比银杏淀粉提高了51.35%、35.66%、120.37%、16.10%。这些加工特性的提高,适应了食品工业的要求,提高了淀粉的加工性能。

The main nutritive component of ginkgo seed is starch. The ginkgo citrate starch ester was prepared from ginkgo starch as raw material and citric acid as esterification agent. The effects of citric acid addition, pH, reaction temperature and reaction time on the degree of substitution of citrate starch ester(DS) were investigated. The optimum preparation process of ginkgo citrate starch ester was determined by orthogonal test. And the processing characteristics of ginkgo starch and ginkgo citrate starch ester were analyzed and compared, such as transparency, expansion rate, solubility, water retention and so on. The results showed that citric acid addition and pH had a significant effect on DS(p<0.05), while reaction temperature had no significant effect on DS(p>0.05). The optimum preparation process of ginkgo citrate starch ester was that citric acid addition amount 8 mL, pH 2.0, reaction temperature 132 ℃, reaction time 6.0 h. The average degree of substitution DS of ginkgo citrate starch ester prepared under these conditions was 0.355. The transparency, solubility, water retention and expansion rate of ginkgo citrate starch ester were 51.35%, 35.66%, 120.37% and 16.10% higher than that of ginkgo starch, respectively. The improvement of these processing characteristics meets the requirements of the food industry and improves the processing performance of starch.