采前处理对双孢蘑菇采后贮藏品质的影响

Effect of Preharvest Treatment on Postharvest Storage Quality of Agaricus bisporus

探讨采前处理对采后双孢蘑菇(Agaricus bisporus)贮藏期间品质的影响。在采收前24 h,分别用0.1、1.0、10.0mg·mL^(-1)的香菇(Lentinula edodes)菌糠提取物(LR-UE)和水杨酸(salicylic acid,SA)溶液均匀喷施子实体表面,喷施量为250 mL·m^(-2),对照组喷施相同量的自来水;采收后分装,置于室温贮藏,贮藏0 d为采收后1 h内的子实体,以后每天取样,直至样品腐烂、褐变或产生异味为止,分别测定外观、白度、硬度、丙二醛(malondialdehyde,MDA)和总酚含量以及多酚氧化酶(polyphenol oxidase,PPO)和苯丙氨酸解氨酶(phenylalanine ammonia lyase,PAL)活性。结果表明:采前子实体表面喷施1.0 mg·mL^(-1)LR-UE和SA的双孢蘑菇在采后贮藏期间均能保持较好的外观、较高的白度和较好的硬度;与对照组相比,采前喷施LR-UE和SA均能有效降低MDA和总酚含量,抑制PPO和PAL活性,且总酚含量与PAL活性变化趋势一致。

In order to study the effects of preharvest treatment on the quality of Agaricus bisporus during postharvest storage,0.1,1.0 and 10.0 mg·mL^(-1)extract of Lentinula edodes spent residue(LR-UE)and salicylic acid(SA)solution were evenly sprayed on fruiting bodies at 250 mL·m^(-2)before harvest,respectively.The same amount of tap water was used as the control.After 24 h,fruiting bodies of different treatments were harvested,packaged and stored at room temperature.Fruiting bodies sampled within 1 h after picking were taken as 0 d storage group,and then fruiting bodies of different treatments were sampled every day to be determined for appearance,whiteness,hardness,malondialdehyde(MDA)concentration,total phenol content,and activities of polyphenol oxidase(PPO)and phenylalanine ammonia lyase(PAL)until the fruiting bodies rotted,turned brown or produced a peculiar odor.The results showed that fruiting bodies sprayed with 1.0 mg·mL^(-1)LR-UE or SA maintained a good appearance,whiteness and hardness during storage.Compared with the control group,spraying with LR-UE or SA before harvest effectively reduced MDA concentration and total phenol content,inhibited PPO and PAL activities,and the variation of total phenol content with time paralleled that of PAL activity.