赤霉素和壳聚糖处理对冷藏毛竹笋保鲜效果的影响

Effects of Gibberellin and Chitosan Treatments on Preservation of Moso Bamboo Shoots in Cold Storage

选择新鲜毛竹(Phyllostachys edulis)笋为对象,分析30 d贮藏期内常温(RT)、低温(LT,4℃),低温+100 mg/L赤霉素浸泡(LT+GA)和低温+1.5%壳聚糖涂膜(LT+CH)4种处理方式对竹笋保鲜效果的影响。结果表明:30 d贮藏期内,竹笋的失重率、过氧化物酶(POD)和苯丙氨酸解氨酶(PAL)活性呈上升趋势,而呼吸速率和可溶性蛋白含量呈降低趋势。低温下3种处理显著抑制竹笋质量降低,30 d时LT、LT+GA和LT+CH下失重率分别为RT处理的34.3%、24.9%和15.2%。贮藏1~7 d内4种处理下竹笋呼吸速率较高且无显著差异,而贮藏30 d LT+GA和LT+CH处理呼吸速率比LT显著降低。与RT相比,低温下3种处理显著抑制POD和PAL活性增加,且LT+CH抑制作用更强,30 d时LT+CH下POD和PAL活性分别比LT低32.2%和35.5%。同时,代表竹笋品质的可溶性蛋白7 d时在LT、LT+GA和LT+CH下比RT处理分别高155%、160%和110%。与常温处理相比,低温及联合赤霉素浸泡和壳聚糖涂膜均能有效抑制竹笋呼吸,降低POD和PAL活性,增加竹笋品质和保鲜时间,4℃低温+1.5%壳聚糖处理效果更好。

In this study,fresh bamboo(Phyllostachys edulis) shoots were selected to compare the preservation effects of the treatments of room temperature(RT),low temperature(LT,4 ℃),low temperature +100 mg/L gibberellin soaking(LT+GA) and low temperature+1.5% chitosan coating(LT+CH) during the 30 d storage period.The results showed that the weight loss rate,peroxidase(POD) and phenylalanine ammonialyase(PAL) activities of the bamboo shoots increased,while the respiration rate and the soluble protein content decreased during the 30 d storage period. The treatments with low temperature significantly inhibited the weight loss of the bamboo shoots.The weight loss rates in LT,LT+GA and LT+CH were respectively 34.3%,24.9% and 15.2% of that in RT treatment after 30 days.The respiration rate was not significantly different among the 4 treatments during 1-7 d storage,however,that in LT+GA and LT+CH was lower than that in LT after 30 d.Compared with RT,the three treatments with low temperature significantly inhibited the increase of POD and PAL activities.The activities of POD and PAL in LT+CH were 32.2% and 35.5% lower respectively than those in LT after 30 d. Meanwhile,the soluble protein,representing the quality of bamboo shoots,was 155%,160%and 110% higher in LT,LT+GA and LT+CH respectively than that in RT after 7 d.Compared with room temperature storage,low temperature and its combination with gibberellin soaking and chitosan coating effectively inhibited the respiration,decreased POD and PAL activity,increased the quality and preservation time of bamboo shoots,while the treatment of 4℃ +1.5% chitosan coating showed preferable preservation effect than other treatments.