Occurrence and diversity of thermophilic sporeformers in French dairy powders

This study reports the prevalence of sporeforming bacteria and contamination levels a variety powdered dairy products from cows', ewes', goats' mares’ milk produced in France. The concentration mesophilic spores, thermophilic spores highly heat-resistant was assessed 61 powders. Thermophilic spore variable between powders, likely due to different manufacturing processes used for transforming into stages processing, particularly heat treatment close 55 °C had strong impact on selection contaminating For some products, counts were as high 5.89 log TSC g−1. Of 313 isolates selected, 93.3% belonged species Geobacillus stearothermophilus (43.5%), Bacillus licheniformis (30.0%) Anoxybacillus flavithermus (19.8%). These results confirm presence three majority reported worldwide.