Final answer:
Microbiology is of lesser concern when the water activity (aw) is low enough to prevent microbial growth. Bacteria require an aw of 0.97 to 0.99, while fungi grow between an aw of 0.8 to 0.75, and methods like drying are used to reduce aw and associated risks.
Step-by-step explanation:
Microbiology is of great concern when it involves the study of organisms that pose a risk to health, whether through diseases in humans or spoilage in food. The level of concern in microbiology, particularly in the prevention of microbial growth, is often associated with the water activity (aw) of an environment, which is a measure of the available moisture for microbial growth. Bacteria generally require a high water activity, specifically an aw of 0.97 to 0.99. In contrast, fungi can grow in drier conditions, typically between an aw of 0.8 to 0.75. Consequently, microbiology might not be of great concern when the water activity is low enough to inhibit the growth of microorganisms. Techniques such as drying, freeze-drying, and adding substances to increase osmotic pressure are utilized to lower the aw and prevent microbial growth, reducing concern in environments such as food preservation or in scenarios where a sterile field is maintained.