Extensive Growth and Growth Boundary Model for Non-Proteolytic <i>Clostridium Botulinum</i> – New Term for Smoke Components and Validation with Map Foods

Abstract

The growth inhibiting effect of smoke components (phenol) and lactic acid bacteria on non-proteolytic Clostridium botulinum were studied. An available cardinal parameter growth and growth boundary model for non-proteolytic C. botulinum (Koukou et al., 2021; https://doi.org/10.1016/j.ijfoodmicro.2021.109162) was expanded with a term for phenol to include the combined inhibiting effect of nine environmental factors. The expanded model was then evaluated using 810 time-to-toxin (TTT) formation data extracted from the scientific literature for seafood, poultry, vegetables and meat products in different atmospheres including air, vacuum or modified atmosphere packaging (MAP) with added CO2. Cold-smoking inhibited growth of non-proteolytic C. botulinum whereas hot-smoking and lactic acid bacteria had no significant inhibiting effect on growth rates (P > 0.2). The expanded model predicted TTT formation without bias (Bf-TTT value = 1.00) and with a reasonable accuracy (Af-TTT value = 1.77). This study substantially increased the range of applicability of the available growth and growth boundary model for non-proteolytic C. botulinum as the expanded model allowed prediction of environmental conditions to prevent growth in seafood (including smoked fish), poultry and vegetable products. It is expected that the expanded model will contribute to product development including development of new sodium reduced foods.