Seasonal Variation of the Microbial Quality of Local Vegetables in Giresun, the Northern Province of Turkey

Abstract

Consumption of vegetables, having a significant place in nutrition of humankind, is increasing day by day as their health-improving effects have been better understood nowadays. The main threat to food safety is pathogenic bacteria that cause several foodborne outbreaks. The microbial quality of vegetables are affected by certain criteria such as organic production, season production, regional production. The objective of this study is to examine the presence of Bacillus cereus and Salmonella spp. in the vegetables sold in markets grown locally in different seasons. The 89 samples, including parsley, lettuce, spinach, turnip, carrot, chard, Brussels sprouts and radish produced in the province of Giresun were analyzed in the study. The presence of Bacillus cereus and Salmonella spp. was determined according to the International Organization for Standardization procedure. Salmonella spp. was not determined in any of the analysed samples. On the other hand, B. cereus was detected in 84 samples with microbial load ranging between 1.0×102 and 4.9×104 CFU/g. Among the samples, the highest B. cereus contamination was observed in lettuce with a 3.1×103 CFU/g. The results showed that B. cereus counts varied by seasons, and the highest count was obtained from the samples grown in spring seasons. Determination of the sources of contamination for the vegetables in pre-harvesting and post-harvesting periods, provides information about the condition of production. The results will help raise the awareness of the farmers about the contamination risks from production to marketing for the prevention of microbial contamination