Saccharomyces cerevisiae: The Scientific Answer
Scientifically, another name for brewer's yeast is Saccharomyces cerevisiae. This single-celled fungus has a rich history, having been used by humans for thousands of years in the production of bread, wine, and beer. The term Saccharomyces means "sugar-mold" or "sugar-fungus," while cerevisiae is derived from the Latin word for "of beer". It is often distinguished from other yeasts by its method of fermentation. As a "top-fermenting" yeast, it rises to the surface during the process, distinguishing it from bottom-fermenting lager yeasts.
Ale Yeast: A Common Brewmaster's Term
In the brewing world, brewer's yeast is also frequently called ale yeast. This name distinguishes it from other types of yeast used in beer production, most notably lager yeast. Ale yeast performs best at warmer temperatures, typically between 15°C and 20°C, and contributes to beers with a richer, fruitier, or spicier aroma and taste. These flavor characteristics are a result of the esters and phenols produced during fermentation. Brewers carefully select specific strains of ale yeast to achieve the desired flavor profile for their particular brew, whether it is a Belgian ale, a traditional British ale, or a modern IPA.
Less Common Names and Variations
While Saccharomyces cerevisiae and ale yeast are the most prevalent alternative names, other terms are sometimes used. These include medicinal yeast, Faex medicinalis, and Saccharomyces carlsbergensis or uvarum, though the latter are now considered synonyms or related species to S. cerevisiae. Furthermore, some brands of nutritional yeast are derived from S. cerevisiae, though their preparation and taste differ significantly from true brewer's yeast. The specific context—whether it's for brewing, supplementation, or scientific study—often dictates the most appropriate name. For instance, dried, inactive brewer's yeast used as a food additive is quite different from the live, active yeast used by a homebrewer.
Brewer's Yeast vs. Nutritional Yeast
It is important to differentiate between brewer's yeast and nutritional yeast, as they are often confused. While both are typically derived from Saccharomyces cerevisiae, they are processed and grown differently, leading to different nutritional profiles and tastes.
Comparison Table: Brewer's Yeast vs. Nutritional Yeast
| Feature | Brewer's Yeast | Nutritional Yeast |
|---|---|---|
| Source | By-product of the beer brewing process, often from malted barley. | Grown specifically for food purposes, typically on sugarcane or molasses. |
| Processing | Inactivated, dried, and often debittered to remove the natural bitterness from hops. | Inactivated and dried; has a savory, cheesy flavor. |
| Flavor | Characteristically bitter and malty. | Cheesy, nutty, or savory. |
| Chromium | Excellent source of the trace mineral chromium, known as Glucose Tolerance Factor (GTF). | Typically not a significant source of chromium unless fortified. |
| Vitamin B12 | Does not contain B12 naturally and is often not fortified with it. | Often fortified with vitamin B12, making it a valuable supplement for vegans. |
| Best For | Lowering blood sugar, boosting energy, and supplementing B-vitamins. | Flavoring vegan dishes, sauces, and toppings due to its cheesy taste. |
The Health Benefits and Uses of Brewer's Yeast
Brewer's yeast is more than just a brewing agent; it's a nutritional powerhouse valued for its health benefits.
Supplementation for Digestive and General Health
As a supplement, brewer's yeast is known for its high content of B-complex vitamins, protein, chromium, and selenium. It is used to support:
- Energy Metabolism: The B vitamins are crucial for converting food into usable energy.
- Blood Sugar Regulation: The chromium in brewer's yeast, particularly the GTF form, may help regulate blood sugar levels by improving insulin function.
- Digestive Health: Some forms of active brewer's yeast can act as a probiotic, supporting a healthy gut microbiome and potentially alleviating symptoms of Irritable Bowel Syndrome (IBS).
- Skin, Hair, and Nails: The high biotin content is often touted for its benefits to skin, hair, and nail health.
Use in Animal Feed
In addition to human supplements, inactive brewer's yeast is a valuable ingredient in animal feed. It serves as a protein and B-vitamin supplement for livestock like pigs, poultry, and fish. Its probiotic effects are also studied for gut health improvements in animals, and it is sometimes used as a palatable flavoring.
Considerations and Side Effects
Despite its benefits, brewer's yeast is not suitable for everyone. Certain individuals should exercise caution or avoid it entirely. People with compromised immune systems, Crohn's disease, or those taking specific medications like MAOIs for depression should consult a healthcare provider before use. Potential side effects for sensitive individuals can include headaches, gas, or stomach discomfort.
Conclusion: More Than Just a Brewing Ingredient
While its primary association is with the brewing industry, another name for brewers yeast is its scientific classification, Saccharomyces cerevisiae, or the brewing term, ale yeast. This potent microorganism is a rich source of B-vitamins, protein, and minerals like chromium and selenium, making it a valued nutritional supplement for both humans and animals. Its processing and uses differ significantly from nutritional yeast, though they share the same base species. Understanding these distinctions and applications highlights why this humble fungus is a superfood with far-reaching applications beyond beer.
Outbound link: Learn more about the biology and applications of Saccharomyces cerevisiae at the Saccharomyces Genome Database.
