Assessment of microbiological quality and safety in frozen ready-to-eat foods in Korea.

The consumption of frozen ready-to-eat (RTE) foods is rapidly increasing in Korea, yet microbial contamination remains a major safety concern. This study evaluated 18 types of frozen RTE foods from retail stores for general microbiological quality and foodborne pathogens, with additional analysis of 20 products from four ingredient categories. Omelet lunchboxes showed the highest contamination, with total aerobic bacteria (7.48 ± 0.55 log CFU/g), coliforms (7.26 ± 0.80 log CFU/g), and yeast/molds (4.03 ± 0.78 log CFU/g). Ingredient-based testing revealed rice cake used in tteokbokki carried the highest microbial loads, including E. coli (4.14 ± 0.03 log CFU/g). Furthermore, 16S rRNA sequencing confirmed that B. cereus was detected in products, including omelets, bibimbap, and lunchboxes, as well as in specific ingredients, such as rice, eggs, fish cakes, japchae, and beef, sourced from highly contaminated products. These findings underscore the urgent need for continuous monitoring, stricter safety standards, and improved handling practices to minimize microbial risks associated with frozen RTE foods.