Evaluation of standard enrichment broths for recovery of healthy and chlorine-injured Escherichia coli O157:H7 cells in
- PDF / 408,299 Bytes
- 7 Pages / 595.276 x 790.866 pts Page_size
- 8 Downloads / 165 Views
Evaluation of standard enrichment broths for recovery of healthy and chlorine-injured Escherichia coli O157:H7 cells in kimchi Hae-Sook Lee1 • Hee-Eun Choi1 • Ung-Kyu Choi1 • Hyun-Gyun Yuk1
Received: 8 April 2020 / Revised: 2 June 2020 / Accepted: 23 June 2020 Ó The Korean Society of Food Science and Technology 2020
Abstract This study aimed to evaluate three standard enrichment broth preparations for the recovery of healthy and chlorine-injured E. coli O157:H7 cells in kimchi. The growth of healthy and chlorine-injured cells in kimchi was observed in three different broths for 24 h. Results showed that the three broths were equally effective for the growth of healthy cells, although the broth described by the International Organization for Standardization (ISO) showed better performance in terms of maximum growth rate when compared to the other two broths described by the Korea Food Code (KFC) and the Food and Drug Administration (FDA). In the case of chlorine-injured cells, similar growth patterns were observed in KFC and ISO broths, whereas inhibition or no growth was found in FDA broth. Thus, this study suggests that KFC and ISO broths were more suitable than FDA broth for the enrichment of E. coli O157:H7 cells in kimchi. Keywords Escherichia coli O157:H7 Kimchi Injured cell Enrichment broth Recovery
Introduction Kimchi is a traditional Korean food fermented by lactic acid bacteria and is one of popular side dish in a Korean meal because of its taste and health benefits (Park et al., 2014). The total amount of kimchi production has reached
& Hyun-Gyun Yuk [email protected] 1
Department of Food Science and Technology, Korea National University of Transportation, 61 Daehak-ro, Jeungpyeong-gun, Chungbuk 27909, Korea
about 450,000 tons in 2017 and its exports have constantly increased from 24,742 tons in 2015 to 28,188 tons in 2019 (KATI, 2020), showing that Korean kimchi has been exported to 68 countries including Japan, United States, Hong Kong and Australia (KATI, 2020). The most popular type of kimchi is ‘Baechu-kimchi’ which is generally made with cabbage (Brassica rapa L. subsp. pekinensis) as the main raw material. For the production of commercial kimchi, cabbage is first cut and brined, followed by quick rinsing with water and draining. The drained cabbage is mixed with seasonings, including chili powder, onions, scallions, garlic, and jeotgal. After fermentation with the help of a starter culture or endogenous lactic acid bacteria, commercial kimchi is packaged and placed in the market for sale (Patra et al., 2016). Since cabbage and other ingredients, such as onions and scallions, are cultivated on soil, a possibility of contamination with soil-borne pathogenic bacteria might exist (Lee et al., 2018). In addition, there is no heating step involved during kimchi processing and thus the contaminated pathogens could survive and multiply during transportation and storage as well, which could lead to a foodborne outbreak. In 2012, there was an outbreak by consumption of kimchi contaminated with Esc
Data Loading...
