脉冲强光处理对双孢蘑菇采后贮藏生理及品质的影响

Effects of intense pulsed light treatment on postharvest storage physiology and quality of Agaricus bisporus

为了延长新鲜双孢蘑菇采后的保质期,提高其保鲜品质和经济价值,以新鲜双孢蘑菇为原料,通过探究不同频率的脉冲强光处理(1、2、3Hz)后双孢蘑菇外观品质、水分含量、质构特性、微观结构、抗氧化酶活性等生理指标的变化,研究了脉冲强光处理对双孢蘑菇采后贮藏品质的影响。结果表明,脉冲强光处理能够延缓双孢蘑菇表面褐色斑点出现,使其L*值在贮藏至15 d时保持在90以上,BI、△E*维持在12以下;降低了双孢蘑菇采后的水分流失率,维持双孢蘑菇硬度在17 N以上、弹性在0.75以上;保护细胞膜的完整性,维持组织的致密性,使丙二醛(malondialdehyde,MDA)含量维持在44nmol/g以下,相对电导率维持在15%以下。此外,在贮藏第15天,与CK组相比,脉冲强光处理组多酚氧化酶(polyphenol oxidase,PPO)活性降低11%–18%,总糖含量提高18%–29%,总酚含量提高1%–9%,过氧化氢酶(catalase,CAT)提高21%–67%,显著提高了可溶性固形物含量和抗坏血酸过氧化物酶(ascorbic acid peroxidase,APX)活性(P<0.05)。本研究结果表明脉冲强光技术可以有效提高双孢蘑菇贮藏品质及营养价值,为脉冲强光技术在控制食用菌保鲜方面的应用提供了一定的理论依据。

This study aims at prolonging the postharvest shelf life of fresh Agaricus bisporus fruiting bodies and improving their freshness quality and economic value.The changes in physiological indexes such as appearance quality,moisture content,texture characteristics,microstructure,antioxidant enzyme activity of A.bisporus fruiting bodies were investigated after intense pulsed light treatment at different frequencies(1,2,3 Hz).The effect of intense pulsed light treatment on the storage quality of A.bisporus was also studied.The results showed that intense pulsed light treatment could delay the appearance of brown spots on the surface of A.bisporus fruiting bodies,keep the L*value above 90 and the BI and∆E*below 12 in 15th day of storage,reduce the moisture loss rate of post-harvest,maintain the hardness of A.bisporus fruiting bodies above 17 N and elasticity above 0.75,protect the integrity of cell membrane,maintain the denseness of tissues,maintain the malondialdehyde(MDA)content below 44 nmol/g,and maintain the relative conductivity below 15%.At the 15th day of storage,in comparison with the CK,the intense pulsed light treatment resulted in 11%–18%decrease in polyphenol oxidase(PPO)activity,18%–29%increase in total sugar content,1%–9%increase in total phenol content,and 21%–67%increase in catalase(CAT),significantly increasing the soluble solids(P<0.05).The results of this study showed that the intense pulsed light technology can effectively improve the storage quality and nutritional value of A.bisporus,prolonging the postharvest shelf life of the edible mushrooms.