Understanding Wine Yeast
Wine yeast — specifically Saccharomyces cerevisiae — is the microorganism that converts grape sugar into alcohol and carbon dioxide. It is the engine of fermentation. But yeast does far more than just produce alcohol. During fermentation, yeast cells generate hundreds of secondary metabolites — esters, higher alcohols, aldehydes, and sulfur compounds — that profoundly shape the aroma, flavor, and mouthfeel of the finished wine.
Different strains of S. cerevisiae have been isolated from vineyards and wineries around the world, each with distinct fermentation characteristics. Some ferment aggressively and tolerate high alcohol. Others work slowly and gently, preserving delicate aromatics. Some enhance color extraction in reds. Others metabolize malic acid, softening sharp wines. The strain you choose is one of the most consequential decisions you will make during winemaking.
Cultured Yeast vs. Wild Yeast
Cultured (commercial) yeast strains are selected for predictability, reliability, and specific flavor contributions. When you buy a packet of Lalvin EC-1118 or Red Star Premier Blanc, you are getting billions of cells of a single, well-characterized strain. The fermentation will behave as expected.
Wild (native, indigenous) yeast refers to the mixed population of yeasts naturally present on grape skins and in the winery environment. These include various species of Saccharomyces, Kloeckera, Candida, Hanseniaspora, and sometimes Brettanomyces. Wild fermentations can produce wines of extraordinary complexity — or they can produce vinegar, volatile acidity, and mouse taint. They are unpredictable by nature.
⚠️ Beginners: Use Cultured Yeast
Wild fermentation is fascinating and can yield remarkable results, but it is not for beginners. The risk of spoilage, stuck fermentation, and off-flavors is high without experience and good laboratory tools. Start with cultured yeast for your first several batches. You can experiment with wild fermentation once you have a solid foundation and understand what a healthy fermentation looks, smells, and tastes like.
What Yeast Does During Fermentation
- Converts sugar to alcohol and CO2 — the primary function. One gram of sugar yields roughly 0.5g alcohol and 0.5g CO2.
- Produces flavor and aroma compounds — esters (fruity), higher alcohols (complexity), thiols (tropical notes in Sauvignon Blanc).
- Affects mouthfeel — some strains produce more glycerol, giving the wine a rounder, fuller body.
- Metabolizes acids — certain strains (like 71B) partially metabolize malic acid during fermentation, softening the wine.
- Extracts color — some red wine strains enhance anthocyanin extraction and stability.
- Produces (or avoids) off-flavors — H2S (rotten egg), SO2, acetic acid, and volatile phenols are all yeast-dependent.
Choosing the Right Yeast
There is no single "best" yeast. The right strain depends on four key factors:
1. Grape Variety and Wine Style
Different grapes have different needs. A delicate Pinot Noir benefits from a strain that enhances fruit and color without overpowering the grape's natural character (RC-212). A robust Cabernet Sauvignon can handle an aggressive fermenter that extracts maximum color and tannin (BM 4x4). An aromatic white like Sauvignon Blanc needs a strain that releases and preserves varietal thiols (QA23 or VL3).
2. Fermentation Temperature
Every yeast strain has an optimal temperature range. Some strains (like D-47) produce off-flavors or stall above 68 degrees F. Others (like EC-1118) perform well across a wide range. Match the strain to the temperature you can realistically maintain. If you cannot cool your fermentation below 75 degrees F, do not choose a strain that requires cool conditions.
3. Alcohol Tolerance
If your grapes have high sugar (SG above 1.100, potential alcohol above 14%), you need a strain that can survive at high alcohol levels. Low-tolerance strains (14%) will die before all the sugar is consumed, leaving you with a stuck fermentation and residual sweetness. EC-1118 and Premier Cuvee tolerate up to 18% and are the safest choices for high-sugar musts.
4. Nutrient Requirements
Some strains are nutrient-hungry and will produce hydrogen sulfide (H2S — rotten egg smell) if starved of nitrogen. Others are low-demand and forgiving. If you are new to nutrient management, choose a low-nitrogen-demand strain or plan to supplement with proper yeast nutrients (covered below).
💡 Quick Decision Framework
First batch or unsure? Use EC-1118. It works for everything. Want more character? Match the strain to your grape: RC-212 for Pinot Noir, D-47 for Chardonnay (if you can keep it cool), QA23 for aromatic whites, 71B for semi-sweet or Nouveau styles. High sugar grapes? EC-1118 or K1-V1116. Hot climate, no temperature control? EC-1118 or K1-V1116.
Lalvin Yeast Strains Guide
Lalvin (Lallemand) is the most widely used brand of wine yeast among home winemakers. Their strains are well-documented, consistent, and available everywhere. Here are the essential Lalvin strains:
EC-1118 (Prise de Mousse)
The workhorse of home winemaking. Originally isolated in Champagne, EC-1118 is the most reliable, versatile, and forgiving yeast available. It ferments cleanly and completely across a wide temperature range, tolerates high alcohol, low pH, and high SO2 levels. It produces a neutral flavor profile — it will not add much character, but it will not add any flaws either. EC-1118 is also the standard choice for restarting stuck fermentations.
- Temperature range: 50-86 degrees F (10-30 degrees C)
- Alcohol tolerance: 18%
- Nitrogen demand: Low
- Best for: Any wine, sparkling wine, cider, mead, restarting stuck fermentations
- Flavor contribution: Neutral, clean. Lets the grape speak.
71B-1122
A unique strain that partially metabolizes malic acid during fermentation (up to 20-40%), softening wines that would otherwise be sharp. This makes it excellent for young-drinking wines, semi-sweet styles, and Beaujolais Nouveau-style reds. It also produces fruity esters that enhance aromatic whites and roses.
- Temperature range: 59-86 degrees F (15-30 degrees C)
- Alcohol tolerance: 14%
- Nitrogen demand: Low
- Best for: Semi-sweet wines, blush/rose, young reds, aromatic whites, fruit wines
- Flavor contribution: Fruity esters, softened acidity. Wines are approachable young.
RC-212 (Bourgovin)
Isolated from Burgundy, this is the definitive Pinot Noir yeast. RC-212 enhances fruit character, extracts color efficiently, and produces wines with good structure and mouthfeel. It requires moderate temperatures and adequate nutrition. Popular for Pinot Noir, Merlot, and other medium-bodied reds.
- Temperature range: 64-86 degrees F (18-30 degrees C)
- Alcohol tolerance: 14-16%
- Nitrogen demand: Moderate to high
- Best for: Pinot Noir, Merlot, Zinfandel, Burgundy-style reds
- Flavor contribution: Enhanced berry fruit, spice, good color extraction.
D-47
A premium white wine yeast known for producing full-bodied wines with enhanced mouthfeel and complexity. D-47 contributes to a rich, creamy texture and works beautifully with Chardonnay, especially when oak-aged. However, it is temperature-sensitive — fermentation above 68 degrees F can produce excessive fusel alcohols and off-flavors. Only use D-47 if you can reliably maintain cool fermentation temperatures.
- Temperature range: 59-68 degrees F (15-20 degrees C)
- Alcohol tolerance: 14%
- Nitrogen demand: Low to moderate
- Best for: Chardonnay, rose, mead, white blends
- Flavor contribution: Creamy mouthfeel, enhanced body, floral notes.
⚠️ D-47 Temperature Warning
D-47 is an outstanding yeast — in the right conditions. Above 68 degrees F, it produces harsh fusel alcohols that are detectable as a hot, solvent-like taste. This is not something that ages out. If you cannot keep your fermentation below 68 degrees F consistently, choose QA23 or EC-1118 instead. D-47 is also a poor flocculator — it stays in suspension a long time and can be slow to clear.
K1-V1116
A strong, competitive fermenter originally isolated in Montpellier, France. K1-V1116 is excellent for fresh, fruity whites and roses. It is a reliable fermenter under difficult conditions — low nutrient, low pH, or cool temperatures. It is also a good choice for restarting sluggish fermentations. K1-V1116 produces very low levels of foam and volatile acidity.
- Temperature range: 50-95 degrees F (10-35 degrees C)
- Alcohol tolerance: 18%
- Nitrogen demand: Low
- Best for: Sauvignon Blanc, Chenin Blanc, Gewurztraminer, ice wine, late harvest, country wines
- Flavor contribution: Fresh, fruity, preserves varietal character.
QA23
Specifically selected for aromatic white wines. QA23 excels at releasing and preserving varietal thiols — the compounds responsible for the tropical and citrus aromas in Sauvignon Blanc, Colombard, and other aromatic varieties. It produces clean, crisp wines with excellent aromatic intensity.
- Temperature range: 59-82 degrees F (15-28 degrees C)
- Alcohol tolerance: 16%
- Nitrogen demand: Low to moderate
- Best for: Sauvignon Blanc, Riesling, Pinot Grigio, Albarino, aromatic whites
- Flavor contribution: Tropical fruit, citrus, passion fruit, preserved varietal aromatics.
ICV-GRE
A Grenache specialist strain from the Rhone Valley, but versatile enough for many red and rose wines. ICV-GRE enhances fruit expression and roundness while respecting terroir character. It produces moderate alcohol and good structure, making it suitable for Grenache, Syrah, Mourvedre, and Southern Rhone blends.
- Temperature range: 64-86 degrees F (18-30 degrees C)
- Alcohol tolerance: 15%
- Nitrogen demand: Moderate
- Best for: Grenache, GSM blends, Rhone-style reds, rose
- Flavor contribution: Ripe fruit, roundness, spice, structured tannins.
Lalvin Yeast Comparison Table
| Strain | Temp Range | Alcohol Tolerance | N2 Demand | Flavor Profile | Best For |
|---|---|---|---|---|---|
| EC-1118 | 50-86°F | 18% | Low | Neutral, clean | Any wine, restarts |
| 71B-1122 | 59-86°F | 14% | Low | Fruity, soft acid | Semi-sweet, rose, young reds |
| RC-212 | 64-86°F | 14-16% | Mod-High | Berry, spice, color | Pinot Noir, Merlot |
| D-47 | 59-68°F | 14% | Low-Mod | Creamy, full body | Chardonnay, rose |
| K1-V1116 | 50-95°F | 18% | Low | Fresh, fruity | Aromatic whites, late harvest |
| QA23 | 59-82°F | 16% | Low-Mod | Tropical, citrus | Sauvignon Blanc, Riesling |
| ICV-GRE | 64-86°F | 15% | Moderate | Ripe fruit, spice | Grenache, Rhone reds |
Red Star Yeast Strains
Red Star (Lesaffre) offers a smaller lineup than Lalvin but includes several excellent, widely available strains. They are often slightly less expensive and equally effective.
Premier Classique (formerly Montrachet)
A robust, vigorous fermenter with a strong flavor contribution. Premier Classique produces complex wines with good structure but has a high nitrogen demand. If starved of nutrients, it is notorious for producing hydrogen sulfide (H2S). Best for full-bodied reds and Chardonnay where you want the yeast to contribute character, not just ferment cleanly. Always use with a complete nutrient regimen.
- Temperature range: 59-86 degrees F (15-30 degrees C)
- Alcohol tolerance: 13-14%
- Nitrogen demand: High
- Best for: Full-bodied reds, Chardonnay
- Caution: Prone to H2S if not properly nourished. Not recommended for beginners without nutrient management.
Premier Blanc (formerly Pasteur Champagne)
A strong, clean fermenter similar in character to EC-1118. Premier Blanc is reliable, neutral, and tolerant of high alcohol and difficult conditions. A solid all-purpose choice and the Red Star equivalent of a workhorse yeast.
- Temperature range: 59-86 degrees F (15-30 degrees C)
- Alcohol tolerance: 18%
- Nitrogen demand: Low
- Best for: Any wine, sparkling wine, high-sugar musts
Premier Cuvee
The strongest fermenter in the Red Star lineup. Premier Cuvee is an aggressive, reliable strain that handles high sugar, high alcohol, low pH, and cold temperatures with ease. It produces a very clean, neutral profile. Excellent for sparkling wine base, restarting stuck fermentations, and any situation where you need a yeast that simply will not quit.
- Temperature range: 45-95 degrees F (7-35 degrees C)
- Alcohol tolerance: 18%
- Nitrogen demand: Low
- Best for: High-sugar musts, sparkling wine, restarts, any wine
Pasteur Red
Specifically designed for red wines. Pasteur Red enhances color extraction and produces wines with good tannin structure and berry fruit character. It has moderate alcohol tolerance and moderate nutrient requirements. A solid choice for Cabernet Sauvignon, Merlot, and other full-bodied reds.
- Temperature range: 64-86 degrees F (18-30 degrees C)
- Alcohol tolerance: 16%
- Nitrogen demand: Moderate
- Best for: Cabernet Sauvignon, Merlot, Syrah, bold reds
Specialty and Wild Yeasts
Brettanomyces
Brettanomyces (often called "Brett") is a non-Saccharomyces yeast that produces distinctive flavors described as barnyard, leather, horse blanket, band-aid, or smoky. In small amounts, some winemakers (particularly in traditional Rhone and Bordeaux) consider Brett character a desirable part of complexity. In larger amounts, it is universally considered a fault.
Brett is not something you inoculate with intentionally in home winemaking. It is a contaminant that arrives on equipment, in barrels (especially used barrels), or from the environment. If you detect Brett character, maintain free SO2 levels above 30-35 ppm and keep pH low (below 3.6) to suppress its growth. Prevention through sanitation is the best strategy.
Native (Wild) Fermentation
Some experienced winemakers choose not to inoculate with commercial yeast at all, instead allowing the wild yeasts on the grape skins and in the winery to conduct fermentation. This is sometimes called "natural" or "spontaneous" fermentation.
The process typically unfolds in stages: Kloeckera and Hanseniaspora species dominate the first few days (producing aromatic compounds but little alcohol), then die off as alcohol rises above 3-4%. Native Saccharomyces strains then take over and complete the fermentation.
Wild fermentation can produce wines of greater complexity and sense of place, but the risks are real:
- Stuck fermentation (if no strong Saccharomyces population establishes)
- Volatile acidity (acetic acid production by non-Saccharomyces yeasts)
- Off-flavors and taints (mouse taint, Brett, excessive ethyl acetate)
- Unpredictable timelines and results
🍇 Co-Fermentation: Best of Both Worlds
A middle-ground approach is co-fermentation. Allow wild yeast to start fermentation for 2-3 days to contribute complexity, then inoculate with a strong commercial strain (like EC-1118) to ensure the fermentation finishes cleanly. This gives you some of the aromatic complexity of wild yeast with the reliability of cultured yeast. Add 25 ppm SO2 at crush (enough to slow wild yeast but not eliminate them entirely), wait 24 hours, then pitch your cultured yeast.
Yeast Nutrients and Health
Yeast are living organisms. They need more than sugar to thrive — they require nitrogen, vitamins, minerals, and sterols to build cell walls and reproduce. Nutrient-starved yeast produce hydrogen sulfide (H2S), stall out, or die before fermentation is complete. Proper nutrition is one of the most overlooked aspects of home winemaking, and it is one of the easiest problems to prevent.
Types of Yeast Nutrients
| Product | Type | Contents | When to Use | Dosage |
|---|---|---|---|---|
| DAP (Diammonium Phosphate) | Inorganic nitrogen | Pure nitrogen source | At yeast pitch and 1/3 sugar depletion | 0.5-1g per gallon per addition |
| Fermaid-O | Organic nitrogen | Inactivated yeast, amino acids, vitamins | At 1/3 and 2/3 sugar depletion | 0.5-1g per gallon per addition |
| Fermaid-K | Blended | DAP + inactivated yeast + vitamins + minerals | At yeast pitch and 1/3 sugar depletion | 0.5-1g per gallon per addition |
| Go-Ferm / Go-Ferm Protect | Rehydration nutrient | Vitamins, minerals, sterols for cell membrane integrity | During yeast rehydration only | 1.25g per gram of yeast |
Understanding Nitrogen
Yeast need nitrogen to build proteins and reproduce. The nitrogen available to yeast in grape juice is called YAN (Yeast Assimilable Nitrogen), measured in milligrams per liter. A healthy fermentation needs 200-300 mg/L YAN depending on the sugar level and yeast strain. Most grape musts have 100-250 mg/L naturally. If YAN is low (common in hot climates, drought years, and with certain grape varieties), supplementation is essential.
💡 The SNA Protocol (Staggered Nutrient Additions)
The most effective way to feed yeast is in stages, not all at once. This is called Staggered Nutrient Additions (SNA). The concept is simple: divide the total nutrient addition into 2-3 doses added at specific fermentation milestones. A basic SNA schedule:
- At yeast pitch: Add Fermaid-K (1g/gallon) or DAP (0.5g/gallon)
- At 1/3 sugar depletion (roughly SG 1.060 if you started at 1.090): Add Fermaid-O (1g/gallon)
- At 2/3 sugar depletion (roughly SG 1.030): Final addition of Fermaid-O (0.5g/gallon)
Do not add DAP after the 1/3 sugar break — yeast absorb inorganic nitrogen poorly at that stage, and excess DAP late in fermentation can feed spoilage organisms.
Go-Ferm: The Rehydration Nutrient
Go-Ferm is not a fermentation nutrient — it is a rehydration nutrient. You dissolve it in the warm water before adding yeast. It provides the vitamins, minerals, and lipids that yeast need to rebuild their cell membranes after the stress of being dried. Studies show that yeast rehydrated with Go-Ferm have higher viability, better fermentation kinetics, and lower H2S production. It is cheap insurance.
Rehydration and Pitching
Proper yeast rehydration is the single most impactful step you can take to ensure a clean, complete fermentation. Dried yeast has been stressed by the drying process. The cell membranes are damaged. If you dump dry yeast directly into cold or acidic must, 50-60% of the cells may die on contact. Rehydrating in warm water allows the membranes to repair before being exposed to the hostile environment of grape juice (high sugar, low pH, sulfites).
Standard Rehydration Protocol
- Heat 50ml of clean, chlorine-free water to 104 degrees F (40 degrees C). Use 10x the weight of the yeast in water (5g yeast = 50ml water).
- Sprinkle the yeast on the water surface. Do not stir. Do not submerge. Let it hydrate for 15 minutes.
- Stir gently to create a smooth cream. Let rest another 5 minutes. The mixture should be creamy and slightly foamy — signs of active, healthy yeast.
- Temper the yeast. Add a small amount of must (about equal to the volume of the yeast slurry) to bring the temperature within 10 degrees F of the must. Wait 5 minutes. This prevents thermal shock.
- Pitch. Pour the yeast slurry into the must and stir gently to distribute evenly. Fermentation should begin within 12-24 hours.
Go-Ferm Rehydration Protocol
- Calculate Go-Ferm dose: Use 1.25 grams of Go-Ferm per 1 gram of yeast. For a standard 5g packet, use 6.25g Go-Ferm.
- Dissolve Go-Ferm in 104 degrees F (40 degrees C) water. Use 20x the weight of Go-Ferm in water (6.25g Go-Ferm = 125ml water). Stir until dissolved.
- Cool to 104 degrees F if the solution got too hot. Sprinkle yeast on the surface. Do not stir.
- Wait 15 minutes. Stir gently. Wait 5 more minutes.
- Temper and pitch as described above.
⚠️ Common Rehydration Mistakes
Water too hot (above 110 degrees F): Kills yeast cells instantly. Use a thermometer. Water too cold (below 95 degrees F): Membranes do not repair properly, causing high cell mortality. Rehydrating in juice or must: The high sugar and low pH of grape juice damage unrepaired cell membranes. Always rehydrate in plain water (or Go-Ferm solution) first. Waiting too long before pitching: Rehydrated yeast should be pitched within 30 minutes. If left too long without sugar, cells begin to starve and die.
Troubleshooting Yeast Problems
Slow Start (Lag Phase Over 48 Hours)
If fermentation has not begun within 48 hours of pitching, something is wrong. Possible causes:
- Temperature too low. Yeast are sluggish below 60 degrees F. Warm the must to 65-70 degrees F.
- Too much SO2. If you added more than 50 ppm sulfite, or did not wait the full 12-24 hours before pitching, the SO2 may be suppressing the yeast. Wait, or add a small amount of fresh must.
- Dead yeast. Old or improperly stored yeast may have low viability. Pitch a fresh packet.
- Improper rehydration. If yeast was dumped dry into cold must, most cells may have died. Rehydrate a new packet properly and pitch again.
Stuck Fermentation
A stuck fermentation is one that stops before all the sugar has been consumed (SG above 1.000 with no airlock activity). This is the most common and frustrating problem in home winemaking.
| Cause | Signs | Fix |
|---|---|---|
| Temperature too high or too low | Fermentation slowed, then stopped | Move to 65-75 degrees F range. Give it 24 hours. |
| Nutrient deficiency | H2S smell, sluggish fermentation | Add Fermaid-O (1g/gallon). Gently stir to resuspend yeast. |
| Alcohol toxicity | SG stuck above 1.010 with high ABV | Restart with EC-1118 or Premier Cuvee using the restart protocol below. |
| High residual SO2 | No activity, no obvious cause | Splash-rack to release bound SO2. Re-pitch fresh yeast. |
| pH too low (below 3.0) | Yeast cannot tolerate the acidity | Add calcium carbonate to raise pH to 3.3-3.4, then re-pitch. |
Restart Protocol for Stuck Fermentations
- Rehydrate a fresh packet of EC-1118 with Go-Ferm in 104 degrees F water.
- Build a starter. Add 50ml of the stuck wine to the rehydrated yeast. Wait 15-30 minutes for activity.
- Gradually increase volume. Double the volume with stuck wine every 15-30 minutes until the starter is actively fermenting (about 500ml-1L total).
- Add the starter to the stuck wine. Keep at 65-70 degrees F and monitor SG daily.
- Add Fermaid-O (1g/gallon) to support the new yeast.
Off-Flavors from Yeast
| Off-Flavor | Smells/Tastes Like | Cause | Prevention | Fix |
|---|---|---|---|---|
| H2S | Rotten eggs | Nitrogen deficiency, stressed yeast | Proper SNA nutrient schedule | Splash-rack during fermentation. Add copper sulfate (1/2 tsp of 1% solution per 5 gal) after fermentation if persistent. |
| Fusel alcohols | Hot, solvent, nail polish remover | Fermentation temperature too high | Control temperature (keep below 85F for reds, 68F for whites) | Cannot be removed. May diminish slightly with extended aging. |
| Volatile acidity (VA) | Vinegar, nail polish | Acetobacter or wild yeast contamination | Good sanitation, maintain SO2, minimize air exposure | Cannot be removed once above 0.8 g/L. Prevention only. |
| Ethyl acetate | Nail polish remover (sweet-sour) | Wild yeast early in fermentation | Sulfite at crush, pitch cultured yeast promptly | Splash-rack may reduce mild cases. Severe cases are permanent. |
| SO2 (sulfur dioxide) | Burnt match, pungent | Over-sulfiting or yeast producing excess SO2 | Measure SO2 carefully, choose low-SO2-producing strains | Splash-rack to volatilize excess free SO2. Usually resolves with time. |
Yeast Comparison Matrix
Use this master table to compare all major strains at a glance. Find the right yeast for your grape variety, temperature conditions, and desired wine style.
| Strain | Brand | Temp Range | Alc. Tol. | N2 Demand | Flavor Profile | Best For |
|---|---|---|---|---|---|---|
| EC-1118 | Lalvin | 50-86°F | 18% | Low | Neutral, clean | All-purpose, restarts, sparkling |
| 71B-1122 | Lalvin | 59-86°F | 14% | Low | Fruity, soft acid | Semi-sweet, rose, Nouveau |
| RC-212 | Lalvin | 64-86°F | 14-16% | Mod-High | Berry, spice | Pinot Noir, Burgundy reds |
| D-47 | Lalvin | 59-68°F | 14% | Low-Mod | Creamy, full body | Chardonnay (cool ferment only) |
| K1-V1116 | Lalvin | 50-95°F | 18% | Low | Fresh, fruity | Aromatics, late harvest, ice wine |
| QA23 | Lalvin | 59-82°F | 16% | Low-Mod | Tropical, citrus | Sauvignon Blanc, Riesling |
| ICV-GRE | Lalvin | 64-86°F | 15% | Moderate | Ripe fruit, spice | Grenache, Rhone reds |
| BM 4x4 | Lalvin | 64-82°F | 16% | Moderate | Intense color, full body | Cab Sauv, Syrah, bold reds |
| Premier Classique | Red Star | 59-86°F | 13-14% | High | Complex, structured | Full-bodied reds, Chardonnay |
| Premier Blanc | Red Star | 59-86°F | 18% | Low | Clean, neutral | All-purpose, sparkling |
| Premier Cuvee | Red Star | 45-95°F | 18% | Low | Clean, aggressive | High sugar, restarts, sparkling |
| Pasteur Red | Red Star | 64-86°F | 16% | Moderate | Berry, tannic structure | Cab Sauv, Merlot, Syrah |
Where to Buy Wine Yeast
Wine yeast is inexpensive (typically $1-3 per 5-gram packet, enough for 1-6 gallons) and widely available. Here are your best options:
Online Suppliers
- MoreBeer (morebeer.com) — Excellent selection of Lalvin and Red Star strains. Fast shipping, competitive prices, and a wide range of nutrients and additives.
- Northern Brewer (northernbrewer.com) — Good selection, reliable shipping. Also carries complete winemaking kits and equipment.
- Amazon — Convenient for common strains (EC-1118, 71B, K1-V1116). Check seller ratings and expiration dates. Avoid yeast that has been stored in hot warehouses.
- Midwest Supplies (midwestsupplies.com) — Solid selection, often bundled with other winemaking supplies.
- Adventures in Homebrewing (homebrewing.org) — Good prices on bulk yeast orders.
- Grapestompers (grapestompers.com) — Specialist wine supply shop with knowledgeable staff and full Lalvin lineup.
Local Homebrew Shops
Your local homebrew shop (LHBS) is often the best option. You can inspect the yeast for freshness, ask staff for strain recommendations specific to your grapes and conditions, and avoid shipping delays and heat exposure during transit. Most homebrew shops stock EC-1118, 71B, K1-V1116, and several Red Star strains. Specialty strains may need to be ordered.
💡 Yeast Storage Tips
Store dried yeast packets in the refrigerator (35-45 degrees F) until ready to use. Properly stored, dried wine yeast is viable for 2-3 years past the manufacturing date. Do not freeze yeast — it damages cell membranes. Do not store yeast at room temperature for extended periods — viability drops significantly after 6-12 months at warm temperatures. Always check the expiration date before use. If in doubt, buy fresh.
How Much Yeast Do You Need?
A standard 5-gram packet is designed for 1-6 gallons of must. For best results:
- 1-5 gallons: One 5g packet
- 6-10 gallons: Two 5g packets
- 15-20 gallons: Three to four 5g packets
- Over-pitching is better than under-pitching. Extra yeast will not harm the wine — it means faster, healthier fermentation with less risk of stalling. Under-pitching leads to stressed yeast, slow starts, and off-flavors.