Definition

• The yeast family includes many different species, but the food production industry uses a variety called Saccharomyces cerevisiae. Yeast spores are single-celled, round fungi. When provided with moisture, warmth and a food source, such as sugar, yeast spores rapidly reproduce by dividing and forming new cells.

Manufacture

• The food industry grows yeast in large water-filled vats. The yeast receives sugar as a food source and a steady supply of oxygen. To collect the yeast, a pump removes all water from the tank, and the yeast dries. The dried yeast can then be packaged and used.

Using Dry Yeast

• To use active dry yeast, add a pinch of sugar to warm water and sprinkle the yeast over the water. Let the yeast stand for 10 minutes until frothy and bubbly. Do not use yeast after the expiration date, as most of the yeast will have died.