不同龙眼品种果实成熟时糖含量及其特征研究

Sugar Contents and Composition in the Mature Fruit of Different Longan Cultivars

通过测定37个龙眼品种果实成熟时假种皮中可溶性糖含量,比较不同龙眼品种的糖组分特点与差异。使用高效液相色谱法对糖组分含量进行测定,采用相关性分析和聚类分析法对数据进行分析,将37个龙眼品种进行分类。结果显示,37个龙眼品种果实假种皮在成熟时期TSS含量在16.84%~27.34%之间,假种皮中可溶性糖主要为蔗糖、葡萄糖和果糖,其中蔗糖含量明显高于含量相当的葡萄糖和果糖。相关性分析表明,龙眼果实可溶性固形物（TSS）含量与甜度和总糖含量呈极显著正相关,甜度和总糖含量亦呈极显著正相关。根据不同品种龙眼果实假种皮中蔗糖/己糖的比例可将37个龙眼品种分为蔗糖积累型、中间类型和己糖积累型。

The sugar composition in the mature fruit of 37 longan cultivars were analyzed by using the method of high liquid chromatography. The data were subject to correlation analysis and clustering analysis, and the different longan cultivars were categorized. The TSS content was between 16.84%-27.34%, the soluble sugars were mainly composed of sucrose, glucose and fructose. Among them, the sucrose content was the highest among the three soluble sugars. Correlation analysis showed that the TSS content was very significantly positively correlated with sweetness and with total sugar content similar to the relationship between sweetness and total sugar content in longan fruit. Based on the sucrose/hexose ratio, the tested cultivars could be divided into three different types of sugar composition： sucrose-prevalent type, intermediate type, and hexose-prevalent type.