• Journal of Applied Biological Chemistry
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• v.59 no.1
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• pp.63-68
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• 2016

This study was performed to assess the microbiological quality of Brassica campestris var. narinosa microgreen from harvesting and processing steps. The samples were analyzed for total viable cell counts (TVC), coliforms, Enterobacteriaceae, Escherichia coli, Salmonella spp., Listeria monocytogenes, Vibrio parahaemolyticus, Bacillus cereus, and Staphylococcus aureus. The total viable counts of microgreen (whole leaves) and environment samples from harvesting steps were higher than 6.8 log CFU/g and the contamination level of coliforms in the samples were 3.2 log CFU/g and 3.5 log CFU/g of microgreen and soil, respectively. In case of microgreen samples collected from processing steps, the contamination level of TVC and coliforms were higher in raw materials than samples obtained from later stages of processing, i.e. washing, drain, and final products. The contamination levels of B. cereus in raw materials and environments decreased approximately 1.4 log CFU/g in final products. S. aureus was detected in soil samples but Salmonella spp., Listeria monocytogenes, Vibrio parahaemolyticus and pathogenic E. coli was not detected. In order to identify the sources of contamination for microgreen, the genetic similarity of B. cereus isolates obtained from harvesting and processing steps were compared using the repetitive-sequence-based polymerase chain reaction method. B. cereus isolates obtained from harvesting environments and microgreen were clustered with a similarity greater than 95%. In case of B. cereus isolates obtained from microgreen and environmental samples at processing steps showed low genetic similarity.

• Journal of the FoodService Safety
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• v.2 no.2
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• pp.84-90
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• 2021

This study was performed to assess the microbiological quality and safety of microgreen sampled from harvesting farms and food processing plant in Korea. The samples were analyzed for total viable counts, coliforms, Enterobacteriaceae, Escherichia coli, Salmonella spp., Listeria monocytogenes, Vibrio parahaemolyticus, Bacillus cereus, and Staphylococcus aureus. Total viable counts were highly contaminated in samples collected from farms (7.7~8.2 log CFU/g) and the final products (5.8~7.8 log CFU/g), respectively. B. cereus was detected less than 100 CFU/g, which was satisfied with Korean standards (<1,000 CFU/g) of fresh-cut produce. A predictive model was developed for the changes of total viable counts in microgreens during storage at 5~35℃. The predictive models were developed using the Baranyi model for the primary model and the square root model for the secondary model. The results obtained in this study can be useful to develop the safety management options along the food chain, including fresh-cut produce storage and distribution.