基于品质指标的苹果浊汁品种与产地差异性分析

Discrimination of Cultivar and Geographical Origin of Cloudy Apple Juices Based on Quality Attributes

以来自7个不同主产区的21个主栽品种,共41份苹果鲜果为研究对象,对每个品种鲜榨浊汁的出汁率、浊度、果汁颜色、褐变度、透光率、可溶性固形物、可滴定酸、总酚、糖、有机酸、VC、矿物质、抗氧化性等品质指标进行测定。运用描述性分析、逐步线性判别分析进行数据处理。结果表明:不同品种或不同产地的苹果浊汁,品质差异较大。总体来看,a*值、原始浊度、褐变度、可滴定酸、葡萄糖、蔗糖、苹果酸等指标的变幅均较大,分别为94.07%、70.41%、42.86%、35.26%、42.02%、42.40%、37.69%。对于不同品种的苹果浊汁,由于褐变度、总酚、抗氧化性等色泽品质指标以及糖、酸等营养品质指标间具有较大差异,其分布呈现分散状态。其中新红星品种的褐变度、总酚含量、DPPH自由基清除率等品质指标普遍居高,色泽品质差异最显著。富士品种大部分样品的果糖、葡萄糖、蔗糖、苹果酸等指标含量较高,具有较好的营养品质。然而对于不同产地间的样品,其浊度、可滴定酸、可溶性固形物等加工品质指标具有较大差异,样品分布较为分散。河北省样品的出汁率、原始浊度、可滴定酸等指标普遍较低,加工品质较差。来自山东省不同品种苹果浊汁的样品以及来自不同产地富士苹果浊汁的样品间均具有较大差异,并且分别获得了77.8%和72.7%的判别准确率。以上结果表明,不同产地、不同品种苹果原料制得的苹果浊汁存在较大差异,通过对其品质指标进行差异性分析,可为上游育种与种植产业结构调整提供数据基础;通过判别模型的建立实现品种与产地的识别与预测,可以指导企业对苹果原料进行制汁专用化筛选。

A total of 41 fresh apple samples from 21 varieties were collected from 7 major producing regions for this study.The quality indicators of cloudy juices from these apples were measured,including juice yield,turbidity,color,browning degree,light transmittance,soluble solids,titratable acid,total phenols,sugar,organic acid,VC,minerals,and antioxidant activity.The obtained data were analyzed by general descriptive and stepwise linear discriminant analysis.The results showed that the quality of cloudy apple juices varied with cultivar and geographical origin.Overall,a*value,original turbidity,browning degree,titratable acid,glucose,sucrose and malic acid varied significantly among cultivars(by 94.07%,70.41%,42.86%,35.26%,42.02%,42.40%,and 37.69%,respectively).Due to their significant differences in color quality indicators such as browning,total phenols,antioxidant activity and nutrients such as sugar and acid,the apple juices from different cultivars were distributed dispersively.The browning degree,total phenols content,and 1,1-diphenyl-2-picrylhydrazyl(DPPH)scavenging capacity of the Starkrimson cultivar were generally higher,and the color quality was best.Most Fuji samples were rich in fructose,glucose,sucrose,malic acid and had good nutritional quality.In addition,the samples from different producing areas showed striking differences in turbidity,titratable acid,soluble solids content.The juice yield,original turbidity and titratable acid content of juice samples from Hebei province were generally lowerer and they were not suitable for juice processing.Similarly significant differences were observed among cloudy apple juices from different cultivars in Shandong province and among Fuji cloudy apple juices from different producing areas,and the discrimination accuracy for the cultivars and producing areas were 77.8%and 72.7%,respectively.The above results showed that there were significant differences among apple juices from different cultivars and different producing areas.Analysis of the differences in quality parameters can provide a basis for apple breeding and restructuring of planting industry.Identification and prediction of cultivars and geographical origins based on a discriminant model can provide guidance for apple juice enterprises to choose suitable cultivars for juice processing.