60Co-γ辐照对冷藏蓝莓果实软化相关指标的影响

Effect of 60Co-γ irradiation on softening indices of blueberry fruit during cold storage

中文关键词:  60Co-γ辐照  冷藏  “蓝丰”蓝莓  果实软化  细胞壁多糖  水解酶

英文关键词:60Co-γ irradiation  cold storage  “Blue crop” blueberry  fruit softening  cell wall polysaccharide  hydrolytic enzymes

中文摘要:

      目的 探讨60Co-γ辐照对蓝莓果实软化相关指标的影响。方法 采用0.5、2.5、3.0 kGy辐照剂量处理蓝莓果实, 测定其在冷藏期间腐烂率、失重率、果实硬度、细胞壁物质、细胞壁多糖含量以及细胞壁水解酶活性的变化差异。结果 0.5 kGy辐照对蓝莓冷藏效果不显著, 3.0 kGy辐照加速了冷藏后期果实的变软, 而2.5 kGy辐照通过降低果胶甲酯酶(pectinesterase, PE)、多聚半乳糖醛酸酶(polygalacturonase, PG)、纤维素酶(cellulase, Cx)活性, 有效抑制了水溶性果胶(water soluble pectin, WSP)升高, 延缓了离子型果胶(EDTA-soluble pectin, ESP)、共价结合型果胶(covalent soluble pectin, SCSP)、连接松散半纤维素、连接紧密半纤维素的下降, 贮藏35 d时蓝莓果实的硬度最高(1.08 N), 腐烂率和失重率最低, 明显推迟了果实的软化进程。结论 2.5 kGy 60Co-γ辐照对冷藏蓝莓果实硬度品质有积极影响。

英文摘要:

      Objective To investigate the effect of 60Co-γ irradiation on the softening indices of blueberry fruit. Methods Blueberry fruits were treated by 0.5, 2.5 and 3.0 kGy radiation doses, and the changes of rotting rate, weight loss rate, fruit hardness, cell wall material, cell wall polysaccharide content and cell wall hydrolase activity were measured during cold storage. Results The 0.5 kGy irradiation had no significant effect on blueberry preservation, 3.0 kGy irradiation accelerated the softening process of blueberry fruits in the later stages of refrigeration, and 2.5 kGy irradiation effectively restrained the water soluble pectin (WSP), delayed the EDTA-soluble pectin (ESP), covalent soluble pectin (SCSP), connected loosely hemicellulose, compact connection hemicellulose by lowering the activities of pectinesterase (PE), polygalacturonase (PG), cellulase (Cx). The firmness of blueberry fruit was the highest (1.08 N), and the decay rate and weight loss rate were the lowest when stored at 35 d, which obviously delayed the fruit softening process. Conclusion The 2.5 kGy 60Co-γ irradiation had a positive effect on the firmness quality of blueberry fruit during cold storage.