^(60)Co γ射线辐照对板栗常温贮藏特性的影响

Effect of ^(60)Co γ ray irradiation on storage traits of Chinese chestnut(Castanea mollissima Blume)

【目的】筛选出适合广西本地板栗常温贮藏辐照加工的最佳60Coγ射线剂量。【方法】以广西隆安县的处暑红板栗为材料,比较不同剂量60Coγ射线辐照板栗果实在室温(25～30℃)条件下的保鲜效果,并探讨辐照对板栗致腐微生物的抑制作用。【结果】板栗常温贮藏辐照加工的最佳剂量为0.5kGy,贮藏20d的好果率为92.10%,与未辐照处理相比,可延长货架期10d;板栗致腐微生物的分离及转皿培养结果表明,板栗常温贮藏中所采用的0.3～1.0kGy剂量均未达到对微生物的杀灭作用,高剂量的辐照处理(25.0kGy)可以完全杀灭所有分离获得的致腐微生物,但远远超过板栗的耐受剂量,不能用于板栗的辐照贮藏加工。【结论】板栗常温贮藏辐照加工的最佳60Coγ射线剂量为0.5kGy,但对致腐微生物的直接杀灭作用非常有限。

[Objective]The present experiment was conducted to screen the best irradiation dose for fresh-keeping and process of local Chinese chestnut under ambient temperatures.[Method]Chinese chestnut variety Chushuhong,collected from Long＇an County（Nanning,Guangxi）,was tested to compare the fresh-keeping effect of various 60Co γ irradiation doses on Chinese chestnut at ambient temperature（25-30℃）and its effect on inhibiting microorganism.[Result]Optimum irradiation dose for Chinese chestnut storage was recorded as 0.5 kGy under ambient temperatures,which resulted in good fruit rate of 92.10% after 20 days of storage.The shelf life of fruits was increased by 10 days over the control.The results from isolation and dish-transferring culture of microorganism in fruit showed that on one hand,irradiation dose of 0.3-1.0 kGy could not killed the microorganism,on the other hand high dose（25.0 kGy） was found to be totally detrimental for microorganism,however,it was higher than the tolerance range of Chinese chestnut,thus it can＇t be used for fresh-keeping and storage of Chinese chest.[Conclusion]Regarding Chinese chest irradiation storage at ambient temperature,the best dose was found to be 0.5 kGy,however,it played a limited role in disinfecting fruits with the microorganisms.