振动胁迫对杏果实细胞壁物质代谢的影响

Impact of Vibration Stress on the Cell Wall Metabolism of Apricot Fruits

本试验以新疆赛买提杏为研究材料,网套包装与无网套包装的杏在4℃、90%~95%RH环境下置于自制变频可调幅振动台上,同时进行频率为5 Hz的水平和垂直方向振动处理,模拟低温下汽车运输过程。杏果分别振动12 h、24 h和48 h并在4℃、90%~95%RH条件下贮藏,以不振动果实作为对照。每隔7 d定期取样,分别测定硬度、原果胶、可溶性果胶、纤维素含量以及PG、Cx、β-葡萄糖苷酶的活性,研究振动胁迫对杏果细胞壁物质代谢的影响。试验结果表明,振动胁迫显著促使杏果PG、Cx和β-葡萄糖苷酶的活性升高,加速可溶性果胶和纤维素含量的上升,降低贮藏过程中杏果的硬度和原果胶含量,加速杏果的品质劣变和软化进程。与无网套包装相比,网套包装可抑制杏果以上生理过程的进行,提高硬度,说明在贮藏过程中网套包装比无网套包装更能显著减缓杏果细胞壁物质的代谢和降解。

Xinjiang ＂Saimaiti＂ apricot was the experimental material analyzed in this study. At a temperature of 4 ℃ and a relative humidity of 90%~95%, the apricot fruits with and without foam-net were placed on a homemade vibration table with a controllable amplitude and variable frequency. The vibration treatment was conducted horizontally and vertically at a simultaneous vibration frequency of 5 Hz to simulate vehicle vibration during transportation. The apricot fruits were vibrated for 12 h, 24 h, and 48 h, and stored at 4 ℃ and 90 %~95 % relative humidity. Fruits with no vibration were used as controls. Sampling was carried out every seven days, and fruit firmness, proto-pectin content, water-soluble pectin content, cellulose content, and polygalacturonase（PG）, cellulase（Cx）, and β-glucosidase activities were measured and the effect of vibration stress on the cell wall metabolism of the fruits was studied. The results showed that vibration stress could increase the water-soluble pectin content, cellulose content, as well as PG, Cx, and β-glucosidase activities of apricots. This also decreases the firmness and proto-pectin content of apricots, as well as accelerates the quality deterioration and softening process of apricots. Compared with no foam-net packaging, foam-net could inhibit the above physiological processes and increase the hardness of apricot fruits. This indicates that the cell wall metabolism and degradation of apricots with foam-net packaging were reduced more effectively than those without foam-net packaging during storage.