Application of different coating treatments to enhance storability and fruit quality of pomegranate (Punica granatum L., cv. Wonderful) during prolonged storage

Abstract This study was carried out on pomegranate fruits cv. “Wonderful” with the aim of maintaining fruit quality and water content, reducing weight loss, chilling injury and browning symptoms during cold storage at 5 °C and 90% RH for 60 d followed by simulated shelf life at 20 °C for 14 d. Coating treatments included gum arabic at 5% and 10%, paraffin at 10% and 20%, chitosan at 1% and 2%, and beeswax at 5% and 10%. All conducted coatings treatments significantly maintained fruit quality as compared to the control (uncoated ones). Chitosan at 2% significantly preserved fruit quality, firmness, visual appearance, husk colour, ascorbic acid and anthocyanin content, furthermore it reduced browning, peroxidase enzyme activity and decay incidence. Paraffin at 10% and beeswax at 10% were effective in maintaining fruit water content, in addition to the significant preservation of husk distention using paraffin at 20%, moreover, application of gum arabic at 5% maintained moderate rates of fruit respiration and total soluble solids content as compared to control.

摘要 本研究以‘奇迹’（Wonderful）品种石榴果实为试验材料，旨在维持其在5℃、相对湿度90%（RH）条件下冷藏60天，并随后在20℃模拟货架期14天过程中的果实品质与含水量，降低重量损失、冷害及褐变症状。本研究设置的涂膜处理包括：5%、10%浓度的阿拉伯胶（gum arabic），10%、20%浓度的石蜡（paraffin），1%、2%浓度的壳聚糖（chitosan），以及5%、10%浓度的蜂蜡（beeswax）。与对照组（未涂膜果实）相比，所有涂膜处理均可显著维持果实品质。其中2%浓度的壳聚糖可显著维持果实品质、硬度、外观、果壳色泽、抗坏血酸与花青素含量，同时可显著抑制褐变、过氧化物酶活性及腐烂发生率。10%浓度的石蜡与10%浓度的蜂蜡可有效维持果实含水量；20%浓度的石蜡可显著维持果壳饱满度；与对照组相比，5%浓度的阿拉伯胶可维持适中的果实呼吸速率与总可溶性固形物含量。