【作者】 唐翠娥；

【导师】 梁瑞红；

【作者基本信息】 南昌大学 ， 农产品加工与贮藏工程， 2007， 硕士

【摘要】 薜荔瘦果中籽和花被中富含果胶类物质,是较好的果胶资源,且因其具较高的药用价值和营养价值,目前在国内外市场中供不应求。而果胶为天然提取物,具有多种生理功能,近年来在多个行业应用广泛。本研究采用低温水提法从薜荔籽中提取果胶,对其浸提和分离工艺进行了实验,并分析研究了所得薜荔籽果胶的基本理化性质、流变性和抗氧化性。以果胶提取率为指标,通过单因素和回归设计试验优化出了低温水萃取法提取薜荔籽果胶（WEP）的最佳工艺条件,同时采用传统酸提法制备了薜荔籽果胶（AEP）。比较了乙醇沉淀-真空干燥法和直接喷雾干燥法分离水提薜荔籽果胶的工艺,对这两种分离方法制得的薜荔籽果胶质量进行了比较,结果显示,喷雾干燥法制得的果胶得率和纯度较低,且颜色较深。采用常规方法测定了水提法制得的薜荔籽果胶的基本成分、溶解度、糖组成、分子量以及结构等理化性质,并与酸提薜荔籽果胶进行了比较,结果显示WEP具有色浅、纯度高、灰分低,分子量大等优点,且WEP和AEP具有不同的糖组成和结构。流变学性质研究结果表明:WEP溶液的流动行为属于假塑性流体,其流变学特性受浓度、pH值、盐浓度、金属离子、热处理以及搅拌处理等因素影响较大。与AEP、商品果胶相比,相同浓度各个果胶溶液,WEP粘度最大;且仅WEP具有正触变性和较大的酸度和钙离子敏感性。通过四种不同体系（卵黄脂蛋白脂质过氧化、DPPH自由基、超氧阴离子、羟基自由基）研究了薜荔籽果胶的抗氧化性能。结果表明:WEP对DPPH·和卵黄脂蛋白脂质过氧化具有较明显的清除和抑制作用,而对O^2-·和OH·的清除能力较低。四大体系中,一定浓度WEP的抗氧化作用均高于一定浓度的AEP。更多还原

【Abstract】 The seeds and perianth of Ficus pumila L achene are good resources pectin,and they are of higher potential value in nutrient and medical,therefore their demands exceeds supply in the market both at home and abroad at present.As one kinds of natural extract,pectin has various physiology functions,and has been used in many trades in recent years.In this paper,the pectin from Ficus pumila L seeds was prepared by low-temperature water extract method,and its preparation technology and separation process had been experimentally.In addition,we had analysised the basic physicochemical properties,the rheological property and the oxidation resistance of the pectin obtained.Choosing the extraction content of pectin extracted by low-temperature water extract method（WEP）as an index,the best extracting process was selected with single factor method and orthogonal regression method.Meanwhile,pectin extracted by acid method（AEP）had also been prepared from Ficus pumila L seeds.Two separation methods that were ethanol precipitation-vacuum drying method and spray drying method of WEP were compared,and the qualities of the pectins prepared by this two separation processes were determined and compared.The results showed that the pectin obtained by spray drying had lower yield rate and purity, evenmore its color was rather deep.In the paper,such physical and chemical properties as basic component, solubility,sugar composition,molecular weight and structure of WEP were determined by conventional method,which were compared with AEP.The test results showed that WEP had shallower color,higher purity,lower content of ash and higher molecular weight than that of AEP.Moreover,we found that AEP and WEP had various saccharide composition and structure.The results of rheology test showed that the rheological behavior of WEP was pseudoplastic liquid and its rheological characteristic depended on such factors as concentration,pH values,metallic ions,heat treatment and agitation treatment. Comparison of the rheology WEP,AEP and two commerical pectins,WEP had a maximum viscosity with the same concentration,and only WEP showed positive-thixotropy and strong pH-sensitive and Ca²⁺-sensitivity.Finally,the antioxidant activity of pectins from Ficus pumila L seeds were studied by four different systems（the lipid of yolk,DPPH·,O₂^-·and·OH）.The result showed WEP had obvious effect of scavenging DPPH·and possessed distinct inhibitory effect on the lipid peroxidation of yolk.However,WEP had shown lower scavenging action to O^2-·and OH^-·.At certain concentration,the antioxidant activities of WEP were higher than those of AEP in the four different systems.更多还原