Evaluating the Contamination of Some Iranian most Consumed Spices and Reduction of Microbial Load by UV Radiation

Spices may be contaminated during various stages of harvesting, drying, or transporting. Different methods are used to reduce the microbial level of spices, which has problems such as flavor changes. The purpose of this study was to introduce optimized conditions for UVradiation on the reduction of microbial load of some high-consumption spices. Six types of spices, including turmeric, ginger, red pepper, black pepper, cinnamon, and sumac, were sampled from the Tehran market. Tests were carried out based on reference standards. Infected spices were then exposed to ultraviolet cabinets at 254 nm in thicknesses of 1, 5, 10 mm and 15, 10, and 5 minutes. A microbial test was performed on irradiated samples. According to the results, It was revealed that the time factor on the total count of aerobic mesophilic bacteria of turmeric, red pepper, black pepper, cinnamon, and also on the coliform count of turmeric and red pepper, as well as on the mould count of turmeric, red pepper, and black pepper had a quite significant effect (P<0.01). It was observed that the thickness effect was quite significant on the total count of aerobic mesophilic bacteria, total coliform, and count of mould. It significantly impacted the total count (p<0.01). The results of this study show that irradiation with UV radiation in the optimized condition can reduce the microbial content of spices to an acceptable level.