Busting Myths on Dry Yeast

By Keith Lemcke
February 07, 2024

Even just 25 years ago, commercial brewers were reluctant to consider the use of dry brewing yeast. If you were in conversation with a brewer at a technical conference and the topic turned to using dry yeast, many brewers would share their concerns that dry yeast had issues related to performance and purity.  In today’s brewing market, brewers now embrace the advantages of dry yeast in all their products. So, what changed? While dry yeast quality and variety has improved over the years, the greatest change has involved the dispelling of myths surrounding these important fermentation products.

The homebrewing myth hangover

Homebrewers have used dry yeast ever since it was first introduced. Before brewing-specific strains were created, it was common to use baking yeast for creating homemade beer, wine, cider, grog, hooch, and more! People fermented with whatever dry yeast was available at their local supermarket. Eventually, homebrew kits came onto the market with many including a sachet of unbranded “mystery yeast” that lacked any details on the contents, especially something as important as an expiration date.

By the time homebrewing took hold in the USA in the late 70s and early 80s, followed by the rise of commercial craft brewing, books on the craft of small brewing were setting the tone for how beer was made. Sometimes the information provided in the books lacked a real scientific foundation, yet some of the information they introduced lives in brewing lore to this day. A good example is what was said about dry yeast in the 1995 book “Dave Miller's Homebrewing Guide”, one of the biggest-selling homebrew books of its time. After a short, somewhat antiquated, overview of how dry yeast used to be made, Miller offered this observation:  “The viability of cells and the degree of contamination vary widely. Even among the better brands, there are great differences from one lot to the next.”

Not all dry yeasts are equal

While the first homebrew beer kits contained "mystery yeast" of questionable quality, commercial brewers (and some savvy homebrewers) were using high-quality dry brewing yeast to brew high-quality beers. Yet statements like these in popular homebrewing books have led to a persistent mythology that dry yeast is still somehow inferior to its liquid counterparts. One such myth is that dry yeast lacked the ability to be repitched and reused for subsequent batches of beer. In fact, dry yeast doesn’t differ from yeast that originated as a liquid culture. When repitching a slurry that originates from a dry culture, the same handling techniques and precautions should be used as if repitching from a culture of liquid origins.

Over the three decades since Mr. Miller’s book was introduced, dry yeast has established itself as a trusted tool for breweries large and small, with performance that meets or exceeds that of its liquid counterparts. Throughout the manufacturing process, every key factor of purity and performance undergoes testing to assure the finished products offer the highest level of consistency in brewing application Combine this with the remarkable shelf-stability, and ease of measurement and use that only active dry yeast can provide, dry yeast has advantages that make it the obvious choice of today’s brewer. With some of the world’s best beers being produced with dry yeast, it’s time to consider the early homebrew myths…busted.