Belge Burcu, Comabella Eva, Graell Jordi, Lara Isabel
Departament de Química, Universitat de Lleida, Lleida, Spain Unitat de Postcollita-XaRTA, Universitat de Lleida, Lleida, Spain.
Unitat de Postcollita-XaRTA, Universitat de Lleida, Lleida, Spain Departament de Tecnologia d'Aliments, Universitat de Lleida, Lleida, Spain.
Food Sci Technol Int. 2015 Sep;21(6):416-27. doi: 10.1177/1082013214541863. Epub 2014 Jul 1.
The biochemical processes underlying firmness loss of sweet cherry (Prunus avium L.) fruit are poorly understood. Studies on cell wall metabolism of sweet cherry have been generally undertaken during on-tree development or at harvest maturity, while published reports on postharvest changes are scarce and fragmentary. In this work, cell wall modifications after storage at 0 ℃ were studied in two cherry cultivars ('Celeste' and 'Somerset') displaying different postharvest potential. Firmness was largely determined by the yields of the Na2CO3- and KOH-soluble fractions, enriched in covalently-bound pectins and in matrix glycans, respectively, and correlated well with ascorbic acid contents. The yields of these two cell wall fractions were correlated inversely with pectinmethylesterase and endo-1,4-β-d-glucanase activities, indicating a relevant role of these two enzymes in postharvest firmness changes in sweet cherry. The amount of solubilised cell wall materials was closely associated to the contents of dehydroascorbic acid, suggesting the possible involvement of oxidative mechanisms in cell wall disassembly. These data may help understanding the evolution of fruit quality during the marketing period, and give hints for the design of suitable management strategies to preserve key attributes.
甜樱桃（Prunus avium L.）果实硬度损失背后的生化过程尚不清楚。对甜樱桃细胞壁代谢的研究通常是在树上发育期间或收获成熟时进行的，而关于采后变化的已发表报告则很少且不完整。在这项研究中，我们研究了两个具有不同采后潜力的樱桃品种（‘Celeste’和‘Somerset’）在0℃储存后的细胞壁修饰情况。果实硬度很大程度上取决于Na2CO3可溶性组分和KOH可溶性组分的含量，前者富含共价结合的果胶，后者富含基质聚糖，且与抗坏血酸含量密切相关。这两种细胞壁组分的含量与果胶甲酯酶和内切-1,4-β-D-葡聚糖酶的活性呈负相关，表明这两种酶在甜樱桃采后硬度变化中起重要作用。溶解的细胞壁物质的量与脱氢抗坏血酸的含量密切相关，这表明氧化机制可能参与了细胞壁的分解。这些数据有助于了解甜樱桃在销售期内果实品质的变化，并为设计合适的管理策略以保持关键品质属性提供参考。
