Fermentation is the original biotechnology. At the Wet Lab’s most recent workshop, families at the La Jolla Library learned how yeast convert sugars into carbon dioxide gas and ethanol with fun, hands-on experiments. We started by making “yeast balls” where the yeast cells are embedded in an alginate matrix. The yeast were then exposed to solutions with or without glucose, and the progress of the chemical reaction was monitored with a pH indicator. We also used the Wet Lab’s portable microscopes to observe our yeast and the micro-organisms that make kombucha.