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Understanding Water Activity in Food

Understanding Water Activity in Food

Moist foods – like fresh fruit or raw meat – often have high water activity and spoil quickly. But some foods that seem moist – like jam or pepperoni – don’t spoil as quickly. Why is this? All living things need water to survive. Enzymes and chemical reactions also require water. If water activity is less than 0.6, almost all microbes, including bacteria, molds, and yeasts, stop growing. This means that food can be preserved against spoilage by lowering its water activity – whether by evaporating water away or binding it up. Virtual Labs – Understanding Water Activity familiarizes the user with food science lab equipment and standard techniques for measuring water activity. The interactive animation guides the user through both theory and practice, preparing them for experiences in a real... Show More


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