纳米碳酸钙改性聚乙烯膜对杨梅贮藏品质和生理的影响

Effects of Nano-CaCO_3-modified Low-density Polyethylene Films Packaging on the Quality and Physiology of Chinese Bayberry

杨梅是我国特色优质水果,但采后特别容易腐烂。为探索杨梅果实的保鲜技术,本论文研究了纳米碳酸钙改性聚乙烯膜(NCCLDPE)对2℃下杨梅果实贮藏品质和生理的影响。研究发现,NCCLDPE膜的氧气和二氧化碳的透过率分别为普通LDPE膜的72.39%和81.33%,从而有利于在包装袋内更快的形成低氧和高二氧化碳的环境。NCCLDPE包装比普通包装杨梅果实的腐烂率低23.74%,而硬度和可滴定酸含量方面则NCCLDPE包装比普通包装分别高5.69%和12.07%,NCCLDPE包装比普通包装杨梅果实的总酚和花色苷含量分别高7.63%和14.75%。NCCLDPE包装比普通包装更加有效抑制了果胶酯酶和多聚半乳糖醛酸酶的活性,其活性分别是普通包装杨梅果实的87.92%和92.67%,延缓了杨梅果实原果胶的降解和水溶性果胶的增加,维持了果实的品质和质地。这表明NCCLDPE包装更有利于杨梅果实品质的保持,并在杨梅果实保鲜上显示出潜在的商业应用价值。

Chinese bayberry fruit is a characteristic high-quality fruit in China, but it decays very quickly after harvest. In order to study preservation techniques for Chinese bayberry fruits, the effects of nano-CaCO3-modified low-density polyethylene （NCCLDPE） packaging on the quality and physiology of Chinese bayberry fi＇uit stored at 2 ℃ were investigated. The results showed that the O2 and CO2 transmission rates of the NCCLDPE film were 72.39% and 81.33% of those of low-density polyethylene （LDPE） film, respectively, thus favoring the faster formation of an environment with low O2 and high CO2 levels in the packaging bag. The decay rate of Chinese bayberry fruit in NCCLDPE packaging was 23.74% lower than that in LDPE bags, while the firmness, titratable acid, total phenolic content, and anthocyanin content of Chinese bayberry fruit in NCCLDPE packaging were 5.69%, 12.07%, 7.63%, and 14.75% higher than those in LDPE packaging, respectively. NCCLDPE packaging more effectively inhibited pectin esterase and polygalacturonase activities, which were 87.92% and 92.67% of those in LDPE packaging, respectively. Additionally, NCCLDPE packaging inhibited the degradation of protopectin and increased the water-soluble pectin content. These data suggest that the NCCLDPE packaging is more favorable for maintaining the postharvest quality of Chinese bayberry fruit and may have commercial value for the preservation of Chinese bayberry fruits.