胡萝卜紫薯发酵蔬菜汁营养成分变化及抗氧化性研究
时间:2019-07-30 12:38 来源:毕业论文 作者:毕业论文 点击:次
摘 要: 以胡萝卜、紫薯为原料经乳酸菌发酵制备胡萝卜紫薯发酵蔬菜汁,研究发酵过程中pH 值、总酸、还原糖、总氨基酸等参数的变化,同时对胡萝卜紫薯发酵蔬菜汁的抗氧化性也进行了研究。结果表明:在发酵过程中随着时间的延长,总酸量、总氨基酸量、活菌数呈上升趋势,pH 值呈下降趋势,花青素含量基本保持不变,Vc含量增加了64 %,β- 胡萝卜素的含量有所下降,为初始含量的69.7 %;胡萝卜紫薯发酵蔬菜汁对超氧阴离子有一定的清除能力,能把 Fe 3+ 还原成 Fe 2+,说明胡萝卜紫薯发酵蔬菜汁有一定的抗氧化性。37638 毕业论文关键词:发酵蔬菜汁; 营养成分变化;抗氧化性 Research on the changes of nutrients and antioxidant activity of the fermented vegetable juice by carrot and purple potato Abstract:Fermented vegetable juice was prepared by fermentation of lactic acid bacteria using carrot and purple potato as raw material. The changes of some parameters, such as the pH value, total acid, reducing sugar, total amino acids, were studied during the fermentation process, and antioxidant activity of fermented vegetable juice by carrot and purple potato were also studied. The results showed that with the extension of fermentation time, total acid, total amino acids, live bacteria increased, pH value decreased, the content of anthocyanin remained basically unchanged, the content of Vc increased 64%, and the content of beta carotene decreased to 69.7%. Fermented vegetable juice by purple sweet potato carrot has certain ability of scavenging superoxide anion and reducing Fe 3 + to Fe 2 +, which indicated that fermented vegetable juice by purple sweet potato carrot had the antioxidant activity. Key Words: Fermented vegetable juice ; The changes of nutrients; Antioxidant activity 目 录 摘 要 4 Abstract 5 引言 5 1 材料与方法 6 1.1材料与试剂 6 1.2仪器与设备 6 1.3实验方法 7 1.3.1胡萝卜紫薯发酵蔬菜汁的制备 7 1.3.2还原糖含量的测定 7 1.3.3 β-胡萝卜素的测定 7 1.3.4 总酸的测定 8 1.3.5 pH值的测定 8 1.3.6 活菌数的测定 8 1.3.7花青素含量的测定 9 1.3.8 Vc含量的测定 9 1.3.9 总氨基酸含量的测定 9 1.3.10 抗氧化性的测定 10 2 结果与分析 10 2.1发酵过程中总酸的变化 10 2.2发酵过程中pH的变化 11 2.3发酵过程中总菌数的变化 12 2.4发酵过程中花青素含量的变化 12 2.5发酵过程中Vc含量的变化 13 2.6发酵过程中总氨基酸含量的变化 13 2.7发酵过程中还原糖含量的变化 14 2.8发酵过程中β-胡萝卜素含量的变化 15 2.9抗氧化性研究 15 2.9.1 对超氧阴离子的清除能力 16 2.9.2 对Fe3+还原能力 16 3 结论 17 参考文献 17 致谢 19 胡萝卜紫薯发酵蔬菜汁营养成分变化及抗氧化性研究 引言 随着人民生活水平的不断提高,我国的饮料市场正发生着深刻的变化,对饮料的需求正从过去的美、解渴转向天然、营养、保健的方向值[1]。发酵蔬菜汁是以蔬菜为主要原料,经预处理榨汁,利用乳酸菌发酵而制得的富含乳酸菌的饮品。乳酸发酵是一种冷加工方式,不会降低蔬菜原料的营养价值。相反,乳酸菌利用原料的可溶性物质代谢产生多种氨基酸、文生素和酶;产生有机酸有利于蔬菜汁矿物质钙、磷等的吸收利用,提高了蔬菜汁的营养价值[2]。 (责任编辑:qin) |