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. For such vegetables, certain criteria such as organic production, season production, regional production etc. are taken into consideration. The objective of this study is to research about existence of Bacillus cereus and Salmonella spp. in the locally-grown vegetables offered in local bazaars. Parsley, lettuce, spinach, turnip, carrot, chard, Brussels sprouts and radish produced in the province of Giresun were used in the study. Bacillus cereus and Salmonella spp. analyses were carried out in line with International Organization for Standardization quality standards. Among 89 vegetable samples analyses, Salmonella spp. and B. cereus were not detected in all and 5 of the samples respectively (<10) and 84 samples yielded B. cereus content varying between 1.0×102 and 4.9×104 kob/g. On average terms, lettuce yielded the highest B. cereus content of 3.1×103 kob/g. Although B. cereus content varied by seasons, the vegetable samples taken in spring were observed to have such content to a higher extent. It is significant to determine the main sources of contamination for the vegetables in pre-harvesting and post-harvesting periods, provide healthier production conditions for prevention of microbial contamination and raise the awareness of farmers regarding the contamination risks during the process from production through marketing.