Effect of infant meal home preparation temperature on surviving of Bacillus cereus sensu lato: A case of Bechar city, Algeria

Abstract

This work aimed to enumerate the Bacillus cereus sensu lato from infant’s flour sampled at Béchar city and evaluate its resistance to different heating conditions during meal preparation patterns at home. Our findings revealed a prevalence of 74% with 2.4 to 3.9 CFU/g in the analyzed samples. Regarding the heat resistance at 90 °C to 98 °C, our results showed heat resistance variability which depends on the isolate, for example, D90 °C and zT °C values varied from 3.24 to 5.52 min and 11.56 to 89.74 °C respectively. Then, the decimal reduction (n) was calculated at all preparation temperatures (50, 60, 70, 80, 90 and 100 °C). Low “n” was observed with the preparation at T≤50 °C as recommended by the fabricant. However, at the other temperatures, high “n” was observed at 100°C with median and 95th values of 2.22 and 12.36 respectively. Therefore, bacterial concentrations (99th) were estimated at 0.124 log CFU/g for 100 °C. These concentrations could be increased with bacterial growth during meal storage and then achieve critical concentrations. Thus, the results of this work highlight the interest to establish a risk assessment for babies and to improve the production, preparation, and storage conditions of the infant’s flour.

Keywords

• inactivation modeling
• bacillus cereus
• infant powders
• risk assessment