不同包装对采后莲藕保鲜效果的比较

Effects of Different Packaging on Preservation of Postharvest Lotus Root

摘要:

以新鲜藕节为试验材料，分别采用PE敞口包装袋（PEO）、PE密封包装袋（PES）、气体调节包装袋（MA）、气体湿度调节包装袋（MA/MH）进行包装处理，在4±0.5 ℃和90% RH条件下贮藏，每隔4 d对莲藕的失重率、亮度、褐变度、硬度、呼吸强度、电导率、丙二醛、多酚氧化酶活性、过氧化物酶活性的变化进行测定。结果表明，在贮藏期间MA、MA/MH包装能有效降低失重率，维持莲藕硬度，抑制相对电导率上升，延缓呼吸强度峰值出现，PEO次之，PES最不理想。贮藏16 d时MA、MA/MH组的褐变度与PEO相比低了31.53%、45.91%。在贮藏过程中MA、MA/MH包装降低多酚氧化酶、过氧化物酶活性，延缓其峰值出现时间。贮藏期结束时，MA、MA/MH组丙二醛含量是PEO组的60.91%、45.87%。结果表明，MA、MA/MH包装能够增强莲藕抗逆性，保持其细胞膜结构完整，延长保鲜期，其中MA/MH最适合莲藕保鲜。

Abstract:

Fresh lotus roots were used as experimental materials, PE open bag (PEO), PE sealed bag (PES), modified atmosphere bag (MA) and modified atmosphere humidity control bag (MA/MH) were used for packaging treatment, and the packaged lotus roots were stored at 4±0.5 ℃ and 90% RH. The weight loss, brightness, browning degree, hardness, respiration intensity, relative conductivity, malondialdehyde content (MDA), para-phenol oxidase activity and peroxidase activity of lotus root were measured every 4 days. The results showed that MA and MA/MH packaging could effectively reduce the weight loss rate, maintain hardness, inhibit the rise of relative conductivity, delay the peak of respiratory intensity of lotus roots. The preservation effect of PEO was worser than MA and MA/MH, and PES had the worst effect. The browning degree values of MA and MA/MH treated group were 31.53% and 45.91%, respectively, lower than that of PEO treated group after storage for 16 days. During storage, the para-phenol oxidase activity and peroxidase activity of MA, MA/MH treated group were decreased, and the contents of MDA in MA and MA/MH treated group were 60.91% and 45.87% of that in PEO treated group. In conclusion, MA and MA/MH packaging can enhance the stress resistance, keep the cell membrane structure intact and extend the shelf life of lotus root. Among the four different packages, the MA/MH packaging is the most suitable for the preservation of lotus root.