What is the preferred water activity level for molds?

The preferred water activity level for molds is typically around 0.90. This level of water activity indicates the availability of water for microbial growth. Molds require a certain amount of moisture to thrive, and a water activity level of 0.90 meets this requirement, allowing them to grow and reproduce effectively.

While lower water activity levels, such as 0.70, 0.85, and even 0.95, are significant in understanding microbial growth and food preservation, they do not provide the optimal environment for molds specifically. At 0.70, many molds cannot grow, and while some may start to thrive at 0.85, the 0.90 level is the threshold that supports robust mold proliferation. A water activity level of 0.95 would still support mold growth, but it exceeds the minimum requirement for optimal growth, thus making 0.90 the key value for understanding mold activity and its implications in environmental health contexts.