Enhancing Soybean Sprout Food Safety through Seed Disinfection Treatments.

Soybean sprouts, a traditional vegetable in Asia, are gaining popularity in the U.S. Sprouting conditions could favor propagation of various microorganisms including plant pathogenic fungi. Sprout consumption has been associated with numerous outbreaks of foodborne illness and, in most cases, the pathogens are known to be seed-borne. However, there is little information about seedborne pathogen incidence on soybean seeds for sprout industry in Virginia. Therefore, studies are needed to identify fungi species in Virginia growth environment and to establish risk management strategies to prevent foodborne diseases and sprout quality lost. The objective of this study is to identify seed-borne pathogens and evaluate different decontamination technologies for seeds before sprouting. Seeds from MFS-561, a commercial sprout cultivar, in commercial production fields will be used to identify pathogens and treated with disinfection methods. The internal transcribed spacer (ITS) DNA region of fungi growing on MFS-561 sprouts will be isolated and sequenced as a reference for species identification. Six disinfection treatments including acetic acid (5% for 10 minutes), lactic acid (5% 10 minutes), sodium hypochlorite (2% for 10 minutes), hot water (60°C for 10 minutes), dry heat (50°C for 1 hour) and calcium hypochlorite (20000 ppm for 15 minutes) will be tested on seeds, and their effectiveness on reducing sprout pathogens and impact on sprout characteristics will be evaluated. The result of this study will list soybean sprout pathogens specific in Virginia soybean growing environments, suggest seed disinfection treatments, and eventually enhance soybean sprout food safety in Virginia.