不同成熟度红毛丹果实果肉品质特性及抗氧化活性比较

Comparison of the Fruit Pulp Quality Characteristics and Antioxidant Capacity of Rambutan Fruits with Different Maturity Levels

摘要:

以海南“保研-7号”红毛丹果实为实验原料，在其成熟度分别为三、五、七和十成熟（或称为成熟度30%、50%、70%和100%）时采摘；测定了上述红毛丹果实果肉品质及抗氧化活性指标，包括可溶性固形物（TSS）、可滴定酸（TA）、还原糖、还原型抗坏血酸（AsA）及总抗氧化能力、羟自由基（·OH）清除能力、抗坏血酸过氧化物酶（APX）、过氧化氢酶（CAT）、过氧化物酶（POD）、多酚氧化酶（PPO）等酶活性，以评估成熟度对红毛丹果实果肉品质及抗氧化能力的影响。结果表明：七成熟时，TSS含量17.01%、AsA含量278.13 μg/g均最大、总抗氧化能力151.04 U/g、·OH清除能力79.16%、APX 1.31×104 nmol/(min·g)活性以及CAT 99.86 U/g活性最强，而TA含量最小0.53%、还原糖含量最低57.44 mg/g；而五成熟时，POD活性最大12.22 U/g而PPO活性最小7.33 U/g。综上，不同成熟度的红毛丹果实果肉品质及抗氧化能力存在显著差异；七成熟为海南“保研-7号”红毛丹果实的适宜采收期。本研究结果能为红毛丹采后商品化处理技术体系的完善及贮运保鲜中的品质保持提供理论和技术依据。

Abstract:

Hainan "Baoyan-7" rambutan fruit were used as the experimental raw materials, which were collected at different maturity stages (30 %, 50 %, 70 % and 100 % maturity levels). The fruit pulp quality and antioxidant capacity indices of the above-mentioned rambutan fruits including soluble solid substance (TSS), titratable acid (TA), reducing sugar, reduced ascorbic acid (AsA), total antioxidant capacity, hydroxyl radical (·OH) scavenging ability, and the activities of ascorbic acid peroxidase (APX), catalase (CAT), peroxidase (POD) and polyphenol oxidase (PPO) were determined, in order to evaluate the effects of maturity level on the quality and antioxidant capacity of rambutan fruit. The results showed that at the 70 % maturity level, the TSS content (17.01%), AsA content (278.13 μg/g), total antioxidant capacity (151.04 U/g), ·OH scavenging capacity (79.16%), APX activity [1.31×104 (nmol/min.g)] and CAT activity (99.86 U/g) were all the highest, with the TA content (0.53%) and reducing sugar content (57.44 mg/g) being the lowest; At the 50% maturity level, the POD activity reached the highest (12.22 U/g) and the PPO activity reached the lowest (7.33 U/g). In summary, there are significant differences in the pulp quality and antioxidant capacity of rambutan fruits with different maturity levels. The Hainan "Baoyan-7" rambutan fruit at the 70% maturity level was suitable for harvesting. The results of this research provide theoretical and technical bases for the improvement of post-harvest commercial processing of rambutan fruit and the quality maintenance during storage and transportation.