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Safe Food Preparation

Author(s): Nancy Moreno, PhD, and Paula Cutler, BS.
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Yeast are living organisms that belong to the Kingdom Fungi. Species of the yeast genus Saccharomyces are used in baking and brewing. These yeasts metabolize sugars and produce carbon dioxide as a waste product. In fresh bread dough, the accumulated carbon dioxide makes the bread rise and become spongy. When yeast break down sugar in an environment without oxygen, ethyl alcohol also is produced as a waste product.

This activity begins by asking students to predict what might happen when yeast are “fed” table sugar (sucrose, C12H22O11). Sucrose consists of two smaller sugar molecules (monosaccharides): glucose and fructose.

Funded by the following grant(s)

National Institute of Environmental Health Sciences, NIH

National Institute of Environmental Health Sciences, NIH

My Health My World: National Dissemination
Grant Number: 5R25ES009259
The Environment as a Context for Opportunities in Schools
Grant Number: 5R25ES010698, R25ES06932