【作者】 曹风； 刘璇； 毕金峰； 张彪； 吴昕烨； 李潇；

【Author】 Cao Feng;Liu Xuan;Bi Jinfeng;Zhang Biao;Wu Xinye;Li Xiao;Institute of Food Science and Technology CAAS Key Laboratory of Agro-Products Processing,Ministry of Agriculture;

【机构】 中国农业科学院农产品加工研究所,农业农村部农产品加工重点实验室；

【摘要】 以来自全国7大主产区的10个品种20份苹果样品为研究对象,由每份苹果中细胞壁物质（alcoholinsoluble residue,AIR）提取三种类型果胶:水溶性果胶（water-soluble pectin,WSP）、螯合性果胶（CDTA-soluble pectin,CSP）、碳酸钠果胶（Na₂CO₃-soluble pectin,NSP）,研究分析果胶的半乳糖醛酸（galacturonic acid,GalA）含量、酯化度、重均分子量（weight-average molar mass,Mw）、中性糖含量以及结构官能团,并进行热图分析,观察比较20份苹果样品果胶含量及其结构间的差异性。结果表明,不同品种苹果三种类型果胶的含量及其结构都存在不同程度的差异性,果胶含量范围为14.40 mg GalA/g AIR～215.75 mg GalA/g AIR,差异性显著,最低的是甘肃金冠的CSP,最高的是澳洲青苹的NSP;果胶甲酯化度范围为30.91%～96.29%,CSP的甲酯化度偏高,且大多数为高酯化度果胶;WSP的乙酰化度均在3.5%以下,乙酰化度最高者为甘肃金冠品种,最低者为辽宁华月品种;Mw范围为1.05×10⁵Da～29.55×10⁵Da,品种间差异性显著;果胶的中性糖组成均以鼠李糖、阿拉伯糖、半乳糖、葡萄糖4种单糖居多,岩藻糖、木糖、甘露糖呈微量状态,CSP线性度较高,各果胶结构主要以同型聚半乳糖醛酸和鼠李聚半乳糖醛酸II型为主,并且果胶侧链较多。以上结果表明,不同品种苹果原料中三种类型果胶的含量及其结构存在一定的差异性,通过对果胶指标进行差异性分析,可以实现品种间的分类和识别,具有亲缘关系的品种在热图聚类分析中可聚为一类,这为苹果相关产品的加工以及苹果副产物的利用提供了理论数据基础,也为苹果育种与种植的结构调整提供了理论支持。更多还原

【Abstract】 Twenty apple samples of ten cultivars from seven main producing areas in China were studied.Three types of pectin were extracted from the alcohol-insoluble residue（AIR） of each apple,including water-soluble pectin（WSP）,CDTA-soluble pectin（CSP） and Na₂ CO₃-soluble pectin（NSP）.The galacturonic acid（GalA） content,esterification degree,weight-average molar mass（M_w）,neutral sugar content,and structural functional groups of pectin were analyzed.The heat map analysis were also performed.The content and structure differences among samples’ pectin were compared.The results showed that the content and structure of three types of pectin from various apple cultivars were different in varing degrees.The pectin contents showed significant differences,ranging from 14.40 mg GalA/g AIR to 215.75 mg GalA/g AIR.The lowest one was CSP from Gansu Golden Delicious and the highest one was NSP from Granny Smith.The degree of methoxylation（DM） of pectin ranged from 30.91% to 96.29%,in addition,CSP had higher DM and most of them were high DM pectin.The degree of acetylation（DAc） of WSP was below 3.5%,Gansu Golden Delicious had the highest DAc and Liaoning Huayue had the lowest.M_w rang ed from 1.05 × 10⁵ Da to 29.55 × 10⁵ Da,and there were significant differences among the cultivars.Rhamnose,arabinose,galactose and glucose were four main neutral sugars in pectin,and fucose,xylose and mannose were in trace amount.The linearity of CSP was relatively high,the pectin structure mainly consists of homogalacturonan and rhamnogalacturonan-II,with plenty of side chains.The above results indicated that there were certain differences among the content and structure of three types of pectin from various apple cultivars.Through the differences analysis of pectin,the classification and identification of apple cultivars could be achieved,and apple cultivars with affinity could be clustered together in heat map clustering analysis,which not only provides theoretical data for the processing of apple-related products and the utilization of apple by-products,but also provides theoretical support for the structural adjustment of apple breeding and planting.更多还原