不同保鲜方式对青柠檬护绿效果的研究

Study on the Effect of Different Preservation Methods on the Green Protection of Lemon

为研究壳聚糖涂膜结合1-甲基环丙烯(1-methylcyclopropene,1-MCP)对青柠檬在不同温度下的护绿效果,将处理后的青柠檬置于不同温度保鲜库中,未处理组(CK)为25℃贮藏,处理组分别为1-MCP不同温度贮藏、壳聚糖涂膜加1-MCP不同温度贮藏,所有处理组放入吸水纸且都用微孔保鲜袋处理。定期测定失重率、pH值、褐变度、a*值、VC含量、可溶性固形物(total soluble solids,TSS)含量等相关指标。结果表明,1-MCP和壳聚糖涂膜处理对青柠檬护绿保鲜有一定效果。4℃+1-MCP处理对青柠檬护绿保鲜效果最佳,贮藏到40 d时,失重率、褐变度、a*值、pH值最低,分别为0.013%、0.45、-0.35、2.75,VC含量为最高3.275 mg/mL,TSS含量高出CK组0.4%。因此,化学保鲜剂结合物理方法和低温保藏可有效延缓青柠檬变黄、褐变、VC及TSS含量下降,降低青柠檬失重率。

The effect of chitosan coating combined with the 1-methylcyclopropene(1-MCP)on the preservation of green lemons(treatment group)stored at different temperatures was evaluated.The untreated group was stored at 25℃.All treatment groups were treated on an absorbent paper placed in microporous plastic bags.Weight loss rate,pH,browning degree,a*value,VC content,soluble solids,and other related indices were measured regularly.1-MCP at 4℃provided the best preservation for green and fresh lemons.After 40 days of storage,the weight loss rate,browning degree,a*,and pH values were the lowest(0.013%,0.45,-0.35,and 2.75,respectively).The highest content of VC was 3.275 mg/mL.The soluble solid value was 0.4%higher than that of the CK group.Therefore,the combination of chemical preservative and physical methods can effectively delay yellowing,browning,and VC indices,decrease the soluble solids content of green lemons,and reduce the weight loss rate of green lemons.