Potential of low dose irradiation to maintain storage quality and ensure safety of garlic sprouts

Abstract

Ten days old garlic sprouts were gamma irradiated in the dose range of 0.25–1.25 kGy followed by storage under refrigerated conditions (3 ± 1 °C, RH 85 %) for 15 days. Samples were evaluated at 4 days interval for storage quality parameters and microbial load. Results of the study revealed that gamma irradiation treatment of 1.25 kGy proved significantly (p ≤ 0.05) effective in maintaining the external appearance, texture and appeal of irradiated sprouts throughout the storage. Besides maintaining visual quality, irradiation at 1.25 kGy enhanced the content of total phenols of garlic sprouts and delayed the oxidation of total phenols, total ascorbic acid and chlorophyll degradation during storage. After 15 days of storage, chlorophyll degradation was 54.4 % in control sprouts and 12.7 % in 1.25 kGy treated sprouts; indicating a 4-fold retention of chlorophyll content in sprouts irradiated at 1.25 kGy. Sensory evaluation revealed that control and 0.25 kGy irradiated sprouts were unacceptable only after 12 days of storage, while as sprouts irradiated at 1.25 kGy were in acceptable condition even after 15 days of storage. Microbial analysis indicated that dose of 1.25 kGy inhibited the mold as well as bacterial growth up to 8 days of storage and resulted in around 2 log reduction in yeast and mold count as well as bacterial count after 15 days of storage, therefore ensures both consumer concerns and microbial safety.