There are so many varieties of yeast on the market today and they are not all created equal. Use this quick guide to differentiate between the various forms of yeast and determine which will is best to use in your recipes.
Active Dry Yeast
This yeast requires dissolving in warm liquid prior to adding to a recipe and should not be substituted for Rapid Rise yeast as it does not dissolve as readily and is deactivated at lower temperatures. Active Dry yeast should not be exposed to liquids hotter than 110 degrees Fahrenheit. This yeast is usually sold in small, 1/4-ounce envelopes or 4-ounce jars.
Baker’s yeast is the general term given to all forms of Saccharomyces cerevisiae used to make bread products. Baker’s yeast is available in several forms such as liquid, fresh (or cake), active dry, and instant.
This is the type of yeast used to make beer. Several genera of yeast are used to brew beer, each lending its own flavor and texture characteristics. A deactivated form of brewer’s yeast is also available as a nutritional supplement as it is a good source of minerals and B vitamins. Read labels carefully when purchasing Brewer’s yeast as a nutritional supplement. Only deactivated forms are safe for consumption in such quantities.
Bread Machine Yeast
This yeast is the same as instant yeast. Instant yeast is important for use in bread machines as it does not require re-hydration or dissolving in liquid prior to being added to a recipe. Because this form of yeast is so highly active, it only requires one rise, which also makes it optimal for use in a bread machine. Labeling instant yeast as “bread machine yeast” makes it easier for consumers to choose the correct yeast to use in their bread machines. Using active dry yeast in place of instant in a bread machine may yield inferior results. Bread Machine yeast is often sold in small, 4-ounce jars.
Fresh yeast is sold in compressed or cake form. This type of yeast is extremely perishable, must be kept refrigerated, and should be used within a couple weeks of purchase. To use fresh yeast, it must be dissolved into a liquid prior to adding to a recipe. Fresh yeast should be proofed, or tested for potency, before each use. To proof yeast, dissolve in warm water and add a pinch of sugar. If the yeast does not begin to foam within 5-10 minutes, it is no longer active and should not be used.
Instant yeast is the most active form of yeast commercially available. This yeast does not require dissolving into a liquid before adding to a recipe and often only requires one rise. This form of yeast is very shelf-stable and can be stored in a dry, airtight container at room temperature until the expiration date. Instant yeast is often sold in small 1/4-ounce envelopes or 4-ounce jars.
Liquid yeast was the most popular form used prior to the invention of compressed or cake yeast in the early 19th century. Liquid yeast is basically a slurry of live yeast organisms, flour (or other carbohydrate), and water, similar to a sourdough or bread starter. As long as fresh carbohydrate is added on a regular basis, the organisms will continue to live and replicate.
This is a deactivated form of yeast, which is used as a nutritional supplement. The deactivation of yeast is important because consuming large quantities of live yeast organisms can lead to proliferation throughout the body. Deactivated yeast is a good source of minerals and B vitamins. Nutritional yeast has a nutty or cheese-like flavor and is often used as a topping or seasoning for foods.
Rapid Rise Yeast
This yeast is the same as bread machine or instant yeast and is usually sold in small, 1/4-ounce (or 2 1/4 tsp) envelopes or small, 4-ounce jars. Rapid Rise yeast requires no proofing or dissolving in liquid prior to adding to a recipe. Simply add the dry yeast with the dry ingredients and proceed as usual. Rapid Rise yeast will stay viable in liquids up to 130 degrees Fahrenheit.
This is a concentrated nutritional yeast product often in the form of a paste. Yeast extracts are favored for their pungent, umami flavor. Yeast extracts have a wide variety of uses and have developed a cult following around the world. Popular brands of yeast extract include Marmite and Vegemite.