Development and validation of a predictive model for the effect of temperature, pH and water activity on the growth kinetics of Bacillus coagulans in non-refrigerated ready-to-eat food products

Ourania Misiou; Christina Zourou; Konstantinos Koutsoumanis

doi:10.1016/j.foodres.2021.110705

Development and validation of a predictive model for the effect of temperature, pH and water activity on the growth kinetics of Bacillus coagulans in non-refrigerated ready-to-eat food products

Food Res Int. 2021 Nov:149:110705. doi: 10.1016/j.foodres.2021.110705. Epub 2021 Sep 16.

Authors

Ourania Misiou¹, Christina Zourou¹, Konstantinos Koutsoumanis²

Affiliations

¹ Laboratory of Food Microbiology and Hygiene, Department of Food Science & Technology, Faculty of Agriculture, Aristotle University, 54124 Thessaloniki, Greece.
² Laboratory of Food Microbiology and Hygiene, Department of Food Science & Technology, Faculty of Agriculture, Aristotle University, 54124 Thessaloniki, Greece. Electronic address: kkoutsou@agro.auth.gr.

PMID: 34600697
DOI: 10.1016/j.foodres.2021.110705

Abstract

A cardinal model (CM) for the effects of temperature (range: 32-59 °C), pH (range: 5.0-8.5) and water activity (a_w) (range: 0.980-0.995) on Bacillus coagulans DSM 1 growth rate was developed in brain heart infusion broth (BHI), using the Bioscreen C method and further validated in selected food products. The estimated values for the cardinal parameters T_min, T_opt, T_max, pH_min, pH_opt, pH_max, [Formula: see text] and [Formula: see text] were 23.77 ± 0.19 °C, 52.89 ± 0.01 °C, 59.37 ± 0.07 °C, 4.70 ± 0.02, 6.43 ± 0.02, 8.56 ± 0.01, 0.969 ± 0.0007 and 0.998 ± 0.0011, respectively. The growth behaviour of B. coagulans was studied in five commercial non-refrigerated ready-to-eat food products under static conditions at 53 °C in order to estimate the optimum specific growth rate for each tested food product. The developed models were validated in the five selected food products under four different dynamic temperature profiles by comparing predicted and observed growth behaviour of B. coagulans. The validation results indicated a good performance of the model for all tested products with the overall Bias factor (B_f) and Accuracy factor (A_f) estimated at 1.00 and 1.12, respectively. The developed model can be considered an effective tool in predicting B. coagulans growth and spoilage risks of non-refrigerated ready-to-eat food products during distribution and storage.

Keywords: Bacillus coagulans; Cardinal model; Climate change; Food spoilage; Growth kinetics; Temperature; Water activity; pH.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Bacillus coagulans*
Food Microbiology
Hydrogen-Ion Concentration
Kinetics
Temperature
Water

Substances

Water