Effects of gamma irradiation, osmotic and freezing processes on chemical, microbial, and pest characteristics of dried Iranian barberry fruit during storage

Abstract

Seedless barberry is a medicinal shrub and has been cultivated in Iran for more than two centuries. It is perishable with short shelf-life. Irradiation has shown to improve microbial safety and expands durability of raw fruits. Undoubtedly, current food processes undesirably affect bioactive compounds such as anthocyanins. Fresh barberry fruit was harvested in Birjand city by methods including “cutting branches” and “collecting fallen fruit under shrubs”, which locally are known as “puffy barberry” and “jewel barberry”, respectively. Some of the fresh barberries were treated by osmotic solution and then they have been dried. Untreated dried fruit was processed by freezing. Osmotic and frozen treatments were packed in polyamide film. Some of the dried jewel/puffy barberries packed in polyamide film were irradiated at doses of 0, 3, 5, and 10 kGy. All samples were stored at 4 and 25 °C for 6 months. Effects of barberry types (puffy/jewel), processes, storage time and temperature on chemical, microbial, and pest characteristics of dried barberry fruit were evaluated. Puffy barberry gamma irradiated with 5 kGy after 6 months of storage at 4 °C showed acceptable properties. Irradiation and storage at 4 °C were reported as optimal processing and storage conditions for barberry fruit.