负载量调控对杏李‘味帝’果实糖酸组分及风味的影响

Crop load influences the components of sugar,acid and flavor in Prunus domestica×armeniaca ‘Weidi’

为研究不同负载量对其果实糖酸组分及果实风味的影响。采用人工疏果方式调控杏李新品种‘味帝’单株的果实负载量,设置4个不同负载水平的处理及一个对照,采用高效液相色谱法(HPLC)测定不同负载量下果实糖酸组分及其含量,并通过人工感官评价法对果实的风味进行评价。结果表明:1)降低负载量可以显著提高果实纵径、果实横径和单果质量并能显著降低果实硬度;2)同时可以显著提高总糖、蔗糖、葡萄糖、果糖和山梨醇等不同类型糖的含量,其中总糖含量提升达40.94%。相关性分析表明4种类型的糖的含量变化呈极显著相关;3)降低负载量对几种酸的影响呈多元化趋势,其中苹果酸含量显著升高,琥珀酸含量变化不明显,柠檬酸、草酸和奎宁酸含量显著降低,T3水平下总酸含量最高,提高了26.70%;4)随着负载量的减小,T1负载水平的甜度值/总酸与对照相比无显著差异;T2负载水平时,甜度值/总酸显著提升,达到最大,继续减小负载量至T3水平甜度值/总酸变化不明显。T2、T3处理后的果实甜酸风味与对照相比发生显著变化,分别为甜、酸甜,CK与T1的风味均为酸。回归分析表明:减小负载量后,葡萄糖是对总糖含量影响最大的因素,果糖是对甜度影响最大的因素,苹果酸是对甜度值/总酸和总酸影响最大的因素。综合分析认为,在一定范围内,降低负载量可显著提升‘味帝’果实的外观品质,促进4种糖和部分种类酸的积累,从而改善果实甜酸风味。

The effect of different load on fruit quality,soluble sugar and organic acid was studied in order to provide a theoretical basis for efficient cultivation technique with ＇Weidi＇. Four different fruit loads,which were CK （2.74 ± 0.16 fruits cm2 of trunk cross-sectional area）,T1 （2.01±0.15 fruits/cm2）,T2 （1.39 ± 0. 15 fruits/cm2）,T3 （0.71± 0.06 fruits/cm2） ,were implemented by thinning manually. High performance chromatography （HPLC） was used to detect different kinds of soluble sugar in mature fruits,and the flavor was evaluated according to the sensory perception based on organoleptic characteristics. The results indicated, 1 ）With fruit load reducing, average transverse diameter,vertical diameter and fruit weight increased significantly, while the fruit hardness decreased; 2） the contents of sucrose, glucose,fructose and sorbitol increased with decreasing fruit load,while the total sugar increased by 40.94%, and a strong correlation existed between the four kinds of soluble sugar; 3） Among six kinds of organic acid, malic acid content increased significantly,succinic acid content changed slightly, while the contents of citric acid,oxalic acid and quinic acid decreased significantly. The total acid increased by 26.70% at T3 level; （4） With fruit load decreasing,S/a increased and reached its peak at T2 treatment and then decreased. The fruit flavor of T2 and T3 treatment were significantly different from the control. They were sweet and sour-sweet, respectively. The flavor of CK and T1 treatment were both sour. The result of regression analysis between fruit flavor and soluble sugar or organic acid showed that glucose,fructose and malic acid were the most important factor that influenced total sugar, sweetness value, the total acid and S/a, respectively. According the study,crop loads reducing promoted the apperance quality and accumulation of four kinds of sugars and sevaral acids in ＇Weidi＇ ,thus improving the sweet and sour flavor.