低剂量60Coγ射线辐照处理影响贮藏期鲜香菇保鲜效果

Preservative Effects of Low-dose 60Coγ-ray Irradiation Treatment on the Freshness of Fresh Lentinus edodes in Storage

摘要:

此项目研究低剂量60Coγ射线辐照处理对鲜香菇保鲜效果的影响。新鲜香菇分别使用0、1、1.5、2 kGy剂量进行辐照处理之后，贮藏于4±1 ℃、湿度为80±5%的环境，并对其微生物含量、组织硬度、色泽和相关的内源酶活性，例如，超氧化物歧化酶（SOD）、谷胱甘肽还原酶（GR）、苯丙氨酸解氨酶（PAL）、纤维素酶、几丁质酶品质指标进行测定。结果表明：1 kGy的照射剂量显着延迟（4~8 d）果实体软化和褐变的发生。在贮藏过程中，1 KGy照射剂量可以控制抗氧化系统中酶活性的降低，减少纤维素和几丁质的积累，并抑制蘑菇的老化。因此，1 KGy的60Coγ射线辐照能较好的保持香菇的品质特性，达到保鲜的效果。照射剂量在1.5 kGy以上会加快鲜香菇品质劣变。

Abstract:

This study examined the freshness-preserving effect of low-dose 60Co γ-ray irradiation treatment on the freshness of fresh mushrooms. Fresh Lentinus edodes were irradiated with 0, 1, 1.5 or 2 kGy dose, respectively, before being stored at 4±1 ℃ and humidity of 80±5%. Then, the microbial content, tissue firmness, color, and activities of enzymes (superoxide dismutase (SOD), glutathione reductase (GR), phenylalanine ammonia lyase (PAL), cellulase, and chitinase) were measured. Obtained results showed that the exposure to irradiation at a dose of 1 kGy significantly delayed (4~8 days) fruit softening and browning. During storage, the irradiation dose of 1 KGy can control the reduction of enzyme activity in the antioxidant systems, reduce the accumulation of cellulose and chitin, and inhibition the aging of the mushroom. Therefore, the 60Co γ-ray irradiation dose of 1 KGy can help preserve the characteristic quality of fresh mushrooms, but an irradiation doses above 1.5 kGy could accelerate the quality deterioration of fresh mushrooms.