Benoît M A, D'Aprano G, Lacroix M
Canadian Irradiation Centre, INRS-Institut Armand-Frappier, 531 boulevard Des Prairies, Laval, Quebec H7V 1B7, Canada.
J Agric Food Chem. 2000 Dec;48(12):6312-6. doi: 10.1021/jf000543s.
Ionizing treatments were applied at 0.5 kGy, 1.5 kGy, and 2.5 kGy to edible mature mushrooms (Agaricus bisporus, albidus) in order to assess the effect of the gamma-irradiation on some biochemical parameters. Irradiation at doses of 1.5 kGy and 2.5 kGy reduced significantly (p < or = 0.05) the rate of respiration of the mushrooms, compared to that of samples irradiated at 0.5 kGy and nonirradiated control samples (C). Ionizing treatments increased significantly (p < or = 0.05) the phenylalanine ammonia-lyase (PAL) activity and total phenols concentration between days 1 and 4. From days 3-4, to the end of the storage period (day 12), both PAL activity and total phenols in the irradiated samples (I) collapsed to lower values. In contrast, the activity of polyphenol oxidase (PPO) increased until days 7, 9, and 12 for samples treated at 0.5, 1, and 2 kGy, respectively. Color measurements showed a loss of whiteness (L value) during storage. After day 4, however, the effectiveness of gamma-irradiation became apparent, and highest L values were obtained for I only.
为了评估伽马射线辐照对一些生化参数的影响，对可食用的成熟蘑菇（双孢蘑菇、白色变种）施加了0.5千戈瑞、1.5千戈瑞和2.5千戈瑞的电离处理。与0.5千戈瑞辐照的样品和未辐照的对照样品（C）相比，1.5千戈瑞和2.5千戈瑞剂量的辐照显著降低了（p≤0.05）蘑菇的呼吸速率。在第1天到第4天之间，电离处理显著增加了（p≤0.05）苯丙氨酸解氨酶（PAL）的活性和总酚浓度。从第3 - 4天到储存期结束（第12天），辐照样品（I）中的PAL活性和总酚含量均降至较低值。相比之下，分别经0.5千戈瑞、1千戈瑞和2千戈瑞处理的样品，其多酚氧化酶（PPO）的活性分别在第7天、第9天和第12天之前一直增加。颜色测量显示，在储存期间白色度（L值）有所损失。然而，在第4天之后，伽马射线辐照的效果变得明显，仅辐照样品（I）获得了最高的L值。
