|LI, MIAOYUNG - Henan Agricultural University|
|ZHU, YAODI - Henan Agricultural University|
|WEI, QINGYING - Henan Agricultural University|
Submitted to: International Journal of Food Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/26/2019
Publication Date: 6/27/2019
Citation: Li, M., Huang, L., Zhu, Y., Wei, Q. 2019. Growth of clostridium perfringens in roasted chicken and braised beef during cooling-one step dynamic analysis and modeling. International Journal of Food Microbiology. https://doi.org/10.1016/j.foodcont.2019.106739.
Interpretive Summary: Clostridium perfringens is a spore-forming foodborne pathogen commonly found in cooked meat and poultry products. The rapid growth of this pathogen in cooked meats can cause acute abdominal pain and diarrhea. Rapid cooling after cooking is critical to prevent the growth of this pathogen. This research was conducted to study the growth kinetics of this pathogen in commercial products (roasted chicken and braised beef) using one-step dynamic kinetic analysis method and to develop accurate mathematical models to predict its growth under various cooling conditions. The models developed in this study can be used by regulatory agencies and food manufacturers to assess the safety of meat and poultry products.
Technical Abstract: Roasted chicken (RC) and braised beef (BB) are two important commercial products widely available in China. Prepared with a mixture of different spices and other ingredients, these two products may be contaminated with Clostridium perfringens spores that can germinate, outgrow, and multiply to a dangerously high level during cooling after cooking if the cooling process is not sufficiently fast, causing outbreaks of food poisoning due to production of C. perfringens enterotoxin. This study was conducted to investigate the growth of C. perfringens from spores in these two products under various cooling conditions and to develop predictive models. Inoculated samples were exposed to different cooling profiles to observe the bacterial growth. Analyzed with the one-step dynamic kinetic analysis method, various kinetic parameters were determined. The estimated Tmin, Topt, and Tmax were 8.8, 46.4, and 51.5°C in RC, and 10.3, 43.5, and 53.4°C in BB, all agreeing well with the cardinal temperatures of this microorganism in meats. The optimum specific growth rate was 6.06 ln CFU/g per h in RC, and 5.64 ln CFU/g per h in BB. The validation of the kinetic parameters and growth models showed that the RMSE of prediction was relatively low (0.2-0.3 log CFU/g). The majority (94%) of the residual errors of prediction was within ±0.5 log CFU/g, and 76% within ±0.3 log CFU/g of the experimental observations. While accurate, the predictions are mostly fail-safe. The estimated kinetic parameters and predictive models developed in this study can be used to predict the growth of C. perfringens in RC and BB during cooling after cooking to prevent the outbreaks caused by the growth of this pathogen.