LED蓝白复合光对杏鲍菇采后褐变的影响

Effect of LED Blue-white Composite Light on Postharvest Browning of Pleurotus Eryngii

摘要:

摘要:为探究发光二极管（Light emitting diode, LED）光照处理对采后杏鲍菇货架品质的影响。该实验以黑暗处理为对照组1，超市货架照明为对照组2 [28 μmol/(m2.s)]，超市自然照明为对照组3 [4.3 μmol/(m2.s)]，在低温货架条件（12~15 ℃）下，采用不同光质和光密度的LED光对杏鲍菇进行处理，通过表型分析筛选出适宜其贮藏的光照条件为蓝光：绿光：红光＝8.4：2.3：1.3。以该光质配比为处理组，同时做上述三组对照，加做单独蓝光[8 μmol/(m2.s)]阳性对照组，研究LED蓝白复合光对杏鲍菇采后褐变进程的影响。结果表明：与对照组相比，LED蓝白复合光提高了杏鲍菇超氧化物歧化酶、过氧化氢酶等抗氧化酶的活性和DPPH自由基清除能力，降低了其超氧阴离子自由基的产生速率和过氧化氢含量，保护机体免受活性氧损伤，抑制了相对电导率和丙二醛含量的上升，降低了其多酚氧化酶活性，保持了较高的总酚含量，由此延缓杏鲍菇的褐变进程；在第2~8 d时，LED蓝白复合光处理组褐变度较对照组1、2、3分别降低了2.24~5.00、1.59~3.23、0.90~1.77倍。在此基础上，采用主成分分析和相关性分析进行综合评价，结果得出，LED蓝白复合光（蓝光：绿光：红光＝8.4：2.3：1.3）处理可有效延缓杏鲍菇的采后褐变进程，保持其较好的品质。综上，LED蓝白复合光可有效保持杏鲍菇的外观品质，延缓其衰老，为LED光照应用在食用菌保鲜方面提供了理论及技术支持。

Abstract:

Abstract: To investigate the effect of light emitting diode (LED) irradiation on the shelf quality of Pleurotus eryngii after harvest. The Pleurotus eryngii was treated with LED irradiation with different light qualities and densities at the temperature of 12~15 ℃. The treatment without LED irradiation, the light condition of supermarket shelves [28 μmol/(m2.s)] and the supermarket lighting [4.3 μmol/(m2.s)] were used as the control 1, 2 and 3, respectively. Through analyzing the phenotype of Pleurotus eryngii, the light conditions of LED blue-white composite light (blue light: green light: red light=8.4:2.3:1.3) was suitable for storing Pleurotus eryngii. Then, the effect of LED blue-white composite light on the postharvest browning process of Pleurotus eryngii was studied by exploring the light quality ratio selected above as the treatment group. The control groups were set as the same mentioned above, and the blue light [8 μmol/(m2.s)] positive control group was added. The results show that compared with the control group, LED blue-white composite light increased the activity of antioxidant enzymes such as superoxide dismutase and catalase and DPPH free radical scavenging ability of Pleurotus eryngii What’s more, the treatment reduced the production rate of superoxide anion radicals and hydrogen peroxide content, thus, protected the Pleurotus eryngii cell from reactive oxygen species damage and inhibited the increase of relative conductivity and malondialdehyde content. Additionally, the composite LED irradiation reduced the activity of polyphenol oxidase, and maintained a high total phenol content, and consequently, delayed the browning process of Pleurotus eryngii. During days of 2~8, the browning degree of the blue-white composite LED treated group was lower by 2.24~5.00、1.59~3.23、0.90~1.77 times than those of the control 1, 2 and 3, respectively. On this basis, it was found that the blue-white composite LED irradiation (blue: green: red light = 8.4: 2.3: 1.3) was able to alleviate the browning process and maintain the quality of Pleurotus eryngii, through using the method of principal component analysis and correlation analysis. Therefore, this research could provide theoretical and technical support for the application of LED irradiation on the preservation of edible fungi.