The concept of water activity is important to food preservation. When water activity is less than 0.6, almost all microbes, including bacteria, molds, and yeasts, stop growing. Vegetables are usually dried even further, to water activity of 0.3 or 0.2, for quality and storage. Virtual Labs – Controlling Water Activity in Food explores a traditional method of preserving corn by drying. In this virtual laboratory, learners test water activity levels of dried corn and explore how they change under three different storage environments. The interactive animation guides users through the theory and practice of sampling a food product, using a water activity meter, and setting up replicates, to build familiarity with concepts and procedures used in real food science labs. Before beginning this lab, it may be useful to complete Virtual Labs – Understanding Water Activity.
Chemistry
ASSESSMENT MODULE
Ninth grade, Tenth grade, Eleventh grade, Twelfth grade, Undergraduate