Quality characteristics of white button mushrooms (Agaricus bisporus) affected by gamma irradiation and volatile oils during storage

Agaricus bisporus mushrooms contain various bioactive substances, the current study aimed to evaluate the effects of gamma-irradiation (1.5, and 2.0 kGy) and essential oils (EOs) fumigation treatments including; geranium (60, and 80 mu L L-1) as well as lemongrass (40, and 60 mu L L-1) on quality characteristics (color, weight loss, firmness), and microbial properties, as well as total and reducing sugars of mushrooms at 4 degrees C during storage for 12 days. It was found that 40 mu L L-1 lemongrass (L1) showed the highest L* after 12 days of storage so, it gave the greatest impact on reducing browning of mushrooms. Geranium oil (G1) recorded the least increase in weight-loss (3.01 %) after 12 days of storage. Otherwise, the firmness was also significantly inceased in the EOs (60 mu L L-1 of geranium and 40 mu L L-1 of lemongrass) samples compared to the controls and gamma-rays. The EOs achieved slight increases in TSS% compared with other treatments. Also, total sugar content in all treatments showed an overall reduction with storage time. Gamma-irradiation (1.5, and 2.0 kGy) was more efficient in inhibiting the development of mesophilic and psychrophilic count. While, lemongrass treatment (L2) has the lowest count of fungi at the end of storage (0.5 log10 CFU g(-1)). The current findings suggest that and EOs (geranium & lemongrass) and gamma-irradiation are a promise process for maintaining the quality of A. bisporus through refrigeration preservation.