Changes in phenolics,soluble solids,vitamin C,and antioxidant capacity of various cultivars of hardy kiwifruits during cold storage

Food Science and Biotechnology - Hardy kiwifruits (Actinidia arguta) contain various bioactive compounds such as vitamin C and phenolics and can withstand cold temperatures. Changes in soluble...     

响应面设计法优化软枣猕猴桃茎中总生物碱的提取工艺

以软枣猕猴桃茎为原料,采用乙醇超声波提取法提取软枣猕猴桃茎中总生物碱并测定其含量。以乙醇体积分数、超声波时间、料液比3个单因素为自变量,以软枣猕猴桃总生物碱提取量为响应值,进行响应面实验。用酸性染料比色法测定软枣猕猴桃中总生物碱的含量,优化出软枣猕猴桃茎中总生物碱的最佳提取工艺。结果表明:软枣猕猴桃茎总生物碱的最佳提取工艺为:乙醇体积分数72%、超声时间30min、液料比为43倍。在此条件下,用紫外分光光度法测得软枣猕猴桃茎中总生物碱的提取量为0.542mg/g。      

低糖野生软枣猕猴桃果脯工艺优化的研究

对低糖野生软枣猕猴桃果脯的生产工艺条件进行优化。结果表明,低糖软枣猕猴桃果脯最优工艺条件为:采用8成熟新鲜的或速冻的软枣猕猴桃为原料,沸水烫漂60 s,刺孔,0.04%硫酸铜和0.01%硫酸锌溶液护色、0.05%氯化钙溶液硬化,在50%蔗糖溶液、0.07MPa条件下真空渗糖,在0.09MPa条件下真空干燥。在此优化条件下制备的果脯组织形态较饱满,软硬适中,酸甜适口,具有浓郁的软枣猕猴桃风味。     

狗枣猕猴桃叶黄酮提取工艺的研究

以乙醇作为提取剂,采用振荡提取法从狗枣猕猴桃叶中提取黄酮类化合物,研究了乙醇浓度、样品粒度、料液比、浸提温度、浸提时间及浸提次数对提取效果的影响。结果表明,料液比对黄酮提取效果影响最大,其次为提取时间和提取温度,而样品粒度和乙醇浓度影响较小。狗枣猕猴桃叶黄酮的最佳提取工艺条件为:乙醇浓度75%,粒度80目,料液比1∶15,浸提温度80℃,浸提时间2h,浸提次数3次,在此条件下黄酮提取率可达7.250%。     

软枣猕猴桃多糖的免疫活性

利用DEAE-纤维素阴离子交换层析、SephadexG-100凝胶柱层析对微波辅助提取的软枣猕猴桃多糖进行分离纯化,对主要洗脱组分0.1 mol/L盐洗组分的免疫活性进行研究。以正常大鼠为试验对象,设2、10、20mg/(kg.d)3个多糖水平处理,饲养28 d后观察软枣猕猴桃多糖对大鼠免疫器官指数、巨噬细胞吞噬指数及脾淋巴细胞转化指数的影响。试验结果表明,多糖低剂量组[2 mg/(kg.d)]对免疫的促进效果不明显;多糖中剂量组[10 mg/(kg.d)]免疫增强效果明显,与空白对照组差异显著;高剂量组[20 mg/(kg.d)]与中剂量组相比,除免疫器官指数外,其他免疫促进活性无显著差异。     

Effects of simulated digestion in vitro on cell wall polysaccharides from kiwifruit (Actinidia spp.)

Cell wall polysaccharides are resistant to digestion and absorption in the human small intestine and are considered to be delivered to the colon in a chemically unaltered state. In this paper, pulp from green and gold kiwifruit was subjected to in vitro upper-intestinal tract digestion and the chemical and physical changes to cell wall polysaccharides (dietary fibre) were investigated. Yields of insoluble fibre decreased slightly with simulated digestion while soluble fibre yields increased. Constituent sugar and glycosyl linkage analysis of the soluble and insoluble fibre fractions revealed that the chemical composition and structure of the non-starch polysaccharides remained largely unchanged. However, the degree of methylesterification of galacturonic acid residues present in the pectin-rich soluble fibre fractions of both fruit decreased with treatment; size-exclusion chromatography detected changes in the molecular weight profiles of these fractions. These changes may affect the physicochemical properties and fermentability of kiwifruit dietary fibre in the large intestine.     

中华猕猴桃果多糖的分离纯化与抗肿瘤试验研究

从中华猕猴桃果中提取粗多糖FP，FP经阴离子交换层析得到多糖FP1和FP2。采用S180移植瘤模型，考察FP、FP1和FP2的抗肿瘤作用。结果表明，多糖FP2具有显著的抗肿瘤活性，在150mg／kg的给药剂量下，对S180肿瘤细胞的抑制率达到54．2％。凝胶过滤层析表明，FP2为单一的组分。纸层析表明，FP2含有D-葡萄糖、D-甘露糖和D-半乳糖。     

1-MCP结合开孔包装对软枣猕猴桃果实软化的研究

目的 采后1-甲基环丙烯（1-MCP）处理缓解软枣猕猴桃开孔包装贮藏失水引起的果实软化问题。方法 以“龙城二号”软枣猕猴桃为材料,0.5μL/L的1-甲基环丙烯（1-MCP）熏蒸结合开孔包装进行贮藏,探究贮藏期间1-MCP结合开孔包装对软枣猕猴桃果实软化的影响。结果 1-MCP处理结合开孔包装与对照相比更有利于保持果实外观,明显抑制了果实中维生素C和总酚的降解;此外,1-MCP处理还延缓了果实硬度的下降,可能是由于抑制了细胞壁降解酶多聚半乳糖醛酸酶（PG）和纤维素酶（CX）的活性,从而推迟了原果胶和纤维素含量的降低,因此延缓了可溶性果胶含量的升高,与对照组相比,货架期延长了4d。结论 1-MCP结合开孔包装贮藏可以保持果实的感观品质,使细胞壁降解进程受到抑制,进而推迟了软枣猕猴桃开孔包装贮藏中轻度失水导致的软化进程,达到了改善果实软化的目的。     

野生软枣猕猴桃果醋饮料的研制

以野生软枣猕猴桃为主要原料,经酒精发酵、醋酸发酵后获得果醋,然后与其他配料混合调配成较高品质的果醋饮料,通过正交试验等进行优化,确定出最佳工艺条件和配方.