Pitch to Profit
Yeast isn’t just an ingredient, it’s a living, flavor-producing powerhouse of an organism. What other ingredients are still thrivin’ and dividin’ when it comes time to brew another beer? And because of this, brewers are afforded a massive opportunity to be their own propagators. Keep that culture healthy and viable; it will reward you in return. You need it, and it needs you, so why not make it a major focus in your operations? Every brewer should understand the nuances of their yeast cultures’ flavor, smell, appearance, and behavior in fermentation. This makes you proactive rather than reactive, having a strong grasp on consistency and quality.
Today, breweries need to find savings in all aspects of their business. One of the biggest ways to save money when it comes to yeast is from maximizing each culture’s potential. Step one? Set a yeast budget. Know your targets, track your spending, and make data-driven decisions. This is absolutely critical because you cannot make informed, data-driven decisions and achieve the greatest success if you do not have a starting place. What’s too expensive? What cellar practices aren’t worth the effort? We can use this information to identify what products to use, how often these products need to be repitched, and what methods may need to be employed for success. So, what does this look like for nanobreweries?
Nanobreweries may be quick to point out that the lack of frequent brew days or cellar space negates their ability to get much use out of a yeast culture. Combine that with a desire to frequently use different yeast strains and the fact that taprooms and brewpubs often achieve higher margins on pints served over the bar, you may ask how any of this applies. I implore you to reflect on your current standard operating procedures and look for opportunities to increase quality. For nanobreweries, frequent strain changes or limited cellar space might make yeast management seem impractical. But with smart planning, even small breweries can improve quality and cut costs. Over time, these savings add up, whether it’s $50 saved today or thousands over years. So, continue on as we discuss strategies for scheduling, harvesting, and repitching while quantifying cost and methods to save on yeast.
Scheduling and Planning
I can’t emphasize enough that a little foresight goes a long way. Plan and strategize the use of cultures being brought into the brewhouse. A tentative schedule of future batches and styles is an easy-to-implement strategy that can lead to immediate cost savings. Ask yourself which upcoming beers can be fermented with this culture. And how often or frequently will these batches occur? This will help you identify an opportunity for scheduling fermentations so you can capitalize on harvests by minimizing storage time. Using a more flavor-neutral strain makes scheduling easy, but it can be more difficult with seasonal or “one-off” brands. But you can still get creative and schedule a second or even third sequential batch that can utilize any strain. If you’re using a hefeweizen strain, think of other styles that can utilize this strain (dunkelweizen or weizenbock, for instance), and because two banana-flavored beers may not be the best sales strategy, adjust fermentation parameters to make a “cleaner,” reduced-ester version. Think overpitching, spunding valves and pressure, or lowering the fermentation temperature.
When planning new cultures, always document the batch, its original gravity, and the yeast culture generation (if re-pitching). A key strategy for reducing your cost is to use early generations in lower-gravity batches and pitching harvested yeast into higher-gravity beers requiring a larger pitch of yeast. You are your own propagator! High-gravity fermentations present a compounding financial challenge that many brewers overlook. When pitching into wort above 17–18 °Plato (1.070–1.074 specific gravity), breweries face both the immediate cost of doubling their yeast quantity and the hidden expense of losing repitching potential. The extreme conditions of high osmotic pressure and alcohol stress typically degrade yeast health to the point where reuse becomes inadvisable. A more strategic approach begins with mid-gravity wort in the 12–15 °Plato (1.048–1.061 SG) range. These gentler fermentations allow yeast to build biomass and vitality, creating opportunities for extended use. For example, a brewery could pitch fresh yeast into a 15 °Plato (1.061 SG) IPA, harvest healthy cells, and then deploy them in a subsequent 20 °Plato (1.083 SG) imperial stout. This progression not only stretches the initial yeast investment across multiple batches but also ensures the culture is at peak health when facing its most challenging fermentation.
Ensuring Healthy Fermentations
Once you’ve established your yeast strategy, the focus shifts to maintaining optimal fermentation conditions. Malt naturally provides most of the essential nutrients yeast needs — like carbohydrates for energy, vitamins for metabolic function, and amino acids for cellular functioning. These components are rarely deficient in standard all-malt worts, but brewers should remain vigilant in recipes with higher adjunct percentages, low original gravities, or poorly modified malts, as these can create nutritional gaps. Two elements demand particular attention: Oxygen and minerals.
Proper aeration at pitching is critical with liquid cultures because without adequate oxygen, liquid yeast struggles to synthesize sterols and fatty acids for building cell membranes during the growth phase (0–48 hours). This can result in sluggish fermentations and poor attenuation. Adequate oxygenation at pitching is less of a concern if using a dried culture due to sufficient sterol and unsaturated fatty acid reserves to support cell division.
Minerals like zinc and magnesium play equally vital roles as enzyme cofactors, influencing everything from flavor development to cell replication. Zinc deserves special consideration because it readily binds to trub during wort production and fermentation, often leaving insufficient amounts available for yeast metabolism. Over successive generations, this deficiency can progressively weaken cell health and reduce fermentation performance. The financial incentive is clear: Healthy yeast means more reliable fermentations and greater generational longevity, all resulting in high-quality beer. Each additional batch you can brew from a single yeast purchase directly lowers your per-batch cost, transforming what might seem like a minor process detail into a meaningful opportunity for savings. By prioritizing these fundamentals, you’re not just nurturing your yeast, you’re protecting your bottom line.
Monitoring Yeast Health
Do I need to run tests to ensure my parameters are in spec for fermentations? In a perfect world, that would be great, but as a nanobrewery this is not always possible nor absolutely necessary. There are a few key parameters that are cheap and easy to monitor and will give you enough information to make informed decisions about your yeast culture.
Let’s start with recording simple gravity and pH readings, as entry-level equipment is both inexpensive and capable of producing accurate results. The key lies in tracking trends, not just numbers. Daily gravity and pH readings during active fermentation tell a more valuable story than any single data point. Focus on the pH drop within the first 48–72 hours as a reliable indicator of yeast activity and vitality. Healthy fermentations’ pH steadily declines during this time before slightly rising through the end of fermentation. Sluggish drops in these initial hours typically signal trouble and poor yeast health. A tip for identifying poor health early is to closely monitor pH drops about 12–16 hours after pitching because inactivity is easier to correct at this time. It may allow you to employ batch-saving techniques like raising the temperature, adding more dissolved oxygen, supplying yeast nutrients, rousing the yeast with CO2, or pitching actively fermenting cultures from other batches. Document these patterns for each strain to create benchmarks; plot them on a simple Excel graph, and over time you’ll recognize normal behavior versus potential issues.
These observations cost nothing but attention, yet provide critical insights into your yeast’s condition. Consistency matters beyond fermentation metrics. If you want added verification that a culture is healthy, invest in a microscope ($250–$300) and the items necessary to perform cell counts and viability testing. Track and aim for consistent harvest sizes using weight (lbs./kgs) or volume (gal./L), and monitor slurry density by eyeballing a slurry through a sight glass or performing a cell count. Any substantial variations in collected yeast may indicate changing culture health. But remember, even without advanced equipment, consistent tracking of basic parameters gives you most of what you need to produce excellent, consistent beer.
The bottom line? You don’t need a lab to make smart decisions. You just need good habits, basic tools, and an understanding of what “normal” looks like for your yeast.
Harvest and Storage
The culture just fermented a batch exactly to specifications and is ready to be harvested and stored until future use. This is a critical step because you don’t want to negate the success you just observed in fermentation by improperly storing the yeast and impacting its health. Let’s discuss a few key recommendations to ensure you maintain the highest viability and vitality between batches.
Aim to collect your yeast when the beer sits about 1 °Plato (5 gravity points) above terminal gravity, just before initiating a diacetyl rest. At this stage, the most flocculent cells have already settled in the cone, contributing little to finishing fermentation, and the remaining suspended cells will handle the final gravity drop and diacetyl cleanup. By harvesting now, you rescue your yeast from the increasingly harsh conditions of the fermenter, where mounting pressure, rising alcohol levels, and insulating heat can rapidly deplete their energy reserves. This stored energy within the cell, glycogen, is needed when the cells are in storage to maintain their health until the next batch.
Perform standard transfer techniques, keep things clean, and slowly open the valve as you dump trub and transfer yeast into a storage vessel to avoid tunneling. Tunneling occurs when yeast remains impacted on the sides of the cone and prevents the entire slurry from being harvested. Trub dumps are key and can be performed daily during fermentation or when harvesting to avoid capturing dead or compromised yeast cells, hop matter, and coagulated proteins. Once collected, treat your stored yeast with the same care you’d give finished beer: Keep it cold (33–38 °F/1–3 °C) in a sanitized, CO2-purged vessel to minimize oxidation and unwanted metabolic activity. Remember to vent storage vessels daily to prevent CO2 buildup from stressing the cells. Storage time can be a concern for nanobreweries. Aim to repitch as soon as possible, but a rough rule of thumb is to store no more than 2–3 weeks after harvesting a healthy culture, as viability declines noticeably with most strains beyond this window. Note that different strains vary in their ability to maintain health in storage. The only way to truly know how long you may store a culture is by recording daily viability readings and identifying an average length for when declining viability occurs. One last tip: Avoid oxygen and warm temperatures because both will trigger metabolism and cause the yeast to begin consuming its stored energy reserves (glycogen).
Repitching Yeast
Repitching yeast at a consistent pitching rate is one of the best ways to improve your quality, flavor consistency, and generational use. The most accurate way to do this is to pick up a microscope and learn to perform viability and cell counts. However, excellent results can still be obtained through careful estimation and documentation. The foundation lies in establishing three key parameters: Your target pitching rate (typically 7.5–15 million cells/mL or 0.75–1.5 million cells/mL/°P), your estimated slurry concentration (generally 1–2 billion cells/mL), and your estimated viability (usually 80–95% for healthy cultures).
Without a microscope, the key here is that these are estimated values, and below are the steps to perform your own estimated repitching calculations. The calculations follow a straightforward approach: First, determine your total cell count needed to pitch based on batch volume and gravity, then divide by your slurry concentration to find the required volume, and finally, convert to weight, if necessary, using the approximate density of yeast slurry (1.15 g/mL).
Step 1: Calculate the total number of cells for the batch.
1 BBL = 117,348 mL
Pitch Rate (cells/mL) x Starting Gravity (Plato) x Batch Size (mL) = Total Cell Population (cells/mL)
Step 2: Calculate the volume of stored yeast to pitch.
Total Cell Population (cells/mL) / Slurry Density (cells/mL) = Volume of Slurry Density (mL)
Step 3: If necessary, convert to weight.
Volume of Slurry Density x 1.15 (g/mL) = Weight of Slurry (g)
The following table shows examples already calculated for a 7.5-million cells/mL repitching rate.
Methods to Maximize Value
As a brewer, you are a propagator of yeast, so reap the bounty of your efforts and maximize the value of your yeast expenses by strategizing the movement of yeast through your cellar. A simple strategy is to split yeast harvests into two subsequent repitches. The yeast divides anywhere from 3–6x, depending on factors like fermentation temperature, strain, gravity, etc., providing you with much more yeast than initially pitched. You can split these into “cousin” lineages and track them separately as they move through the brewery. Nanobreweries are limited in brewhouse capacity, but utilizing this strategy even once can show worthy savings over time.
Example: Think about a month where you harvest week one, pitch half the harvest into a core high-ABV beer week 2, and pitch the other half into a second core beer week 3. That’s a minimum of three batches with a single purchase, reducing your overall expense to a third of its original cost. It’s not hard to imagine that over the course of a year we are talking about significant savings on yeast expense.
Double batching is another powerful savings tool. By brewing half your fermenter volume one day and completing the fill the next day, you leverage the yeast’s 24-hour growth period to avoid a second pitch. Just pitch to the day-one fill volume. This halves your yeast costs immediately, with compounding savings across generations.
Last, pressurized lager fermentations are becoming more popular, especially with the rebirth of demand for lager brewing in many craft breweries. The concept is that warmer temperatures allow for greater metabolic activity and promote cell division in the initial growth phase. Traditional cold pitching (48–55 °F/9–13 °C) requires nearly double the yeast, but starting at 65–70 °F (18–21 °C) with 1 bar pressure (or 14.5 PSI) promotes natural cell growth while maintaining clean profiles through pressure-induced ester suppression. The benefits multiply: Lower pitch rates, faster fermentations (6–8 days versus 2–3 weeks), and reduced tank time, all while achieving lager character.
Implement, Document, & Save
Don’t cut corners for convenience or upfront savings. Invest in quality yeast, track performance, and stick to your strategy, even if results take 6–12 months to materialize. Document every batch, generation, and cost to refine your process.
Yeast management isn’t just about saving money, it’s about brewing better beer. By treating your cultures as partners, not commodities, you will unlock consistency, creativity, and long-term profitability.
