/ 14 g yeast
Yeast is a rich source of B vitamins (particularly B1, B2, B3, and B5) and selenium; it also contains essential amino acids and mineral compounds. Fresh and dried yeast contribute minimal calories per gram but provide significant micronutrient density.
About
Yeast comprises single-celled microorganisms of the kingdom Fungi, most commonly Saccharomyces cerevisiae, used in fermentation and leavening applications. These living organisms metabolize sugars through anaerobic respiration, producing carbon dioxide and ethanol as byproducts. Yeast exists in multiple forms: fresh (compressed cake), active dry, and instant varieties, each with varying moisture content and particle size. Fresh yeast appears as a pale tan, moist cake with a distinctive earthy aroma; active dry yeast is granulated and dormant until hydrated; instant yeast (also termed bread machine yeast) has smaller particles and activates more rapidly. The fermentation capability and flavor contribution vary by strain and processing method.
Culinary Uses
Yeast serves as the primary biological leavening agent in bread baking, where it ferments dough sugars to produce the carbon dioxide that creates crumb structure and volume. In breweries and distilleries, it ferments sugars in wort or mash to produce beer, wine, and spirits. Beyond fermentation, yeast enriches doughs with complex flavor compounds and improves digestibility through gluten breakdown. Yeast is also used as a nutritional supplement (nutritional yeast) in savory applications for umami depth and B-vitamin fortification. Proper hydration temperatures, fermentation timing, and storage conditions are critical for optimal performance.