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All-grain brewing replaces concentrated malt extract with raw malted grain. You convert the grain’s starches to fermentable sugars yourself through a process called mashing, then proceed through the same boil and fermentation steps as extract brewing. The payoff is complete control over fermentability, grain character, and water chemistry. The cost is an extra 60–90 minutes on brew day and a few hundred dollars of additional equipment.
What you need beyond extract brewing
- Mash tun, insulated vessel to hold grain and water at a stable temperature for 60 minutes. A 10-gallon Igloo cooler with a braided stainless mesh hose or false bottom works reliably and costs $40–60 DIY. Commercial mash tuns with false bottoms run $80–150.
- Larger brew kettle, all-grain requires a full-volume boil (6–7 gallons for a 5-gallon batch). An 8–10 gallon kettle minimum; 10–15 gallon is better.
- Wort chiller, chilling 6+ gallons from boiling takes 45+ minutes with an ice bath. A 25-foot immersion chiller ($45–65) gets you there in 15–20 minutes.
- Grain mill, optional if your homebrew shop crushes grain for you, necessary if you buy whole malt. A two-roller mill like the Monster Mill MM-2 runs $50–90.
The cheapest viable all-grain setup is a 10-gallon cooler mash tun + an 8-gallon kettle on a propane burner outdoors + an immersion chiller. Budget $150–200 added to your existing extract equipment.
Step 1: Mill your grain
Crush the malt just before brewing, pre-ground malt stales within a few days as oxidation affects the enzymes. The goal is cracking the grain husks to expose the starchy interior while keeping the husks largely intact. Husks act as a natural filter bed during lautering. Over-crush and you get a stuck mash; under-crush and you lose conversion efficiency. A two-roller mill at the factory gap setting (typically 0.039–0.045 inches) handles most base malts correctly.
Step 2: Mash, converting starches to sugar
Heat your strike water to 168–172°F/75–78°C (about 5–10°F above your target mash temperature to account for heat loss when adding grain). Add the grain to the mash tun, pour in the hot water, and stir thoroughly. Check temperature with a probe thermometer. For most beers, target 152–154°F/67–69°C and hold for 60 minutes.
Temperature directly shapes the beer’s body and fermentability. Beta-amylase enzymes are most active at 145–155°F/63–68°C and produce highly fermentable wort (drier, thinner beer). Alpha-amylase dominates above 158°F/70°C and produces less fermentable, fuller-bodied beer. Most ales hit a sweet spot at 152–154°F/67–69°C, use the lower end for dry styles like saisons or session IPAs, the higher end for malty amber ales and stouts. The AHA’s all-grain brewing guide covers mash chemistry in more depth.
Step 3: Mash out and vorlauf
After 60 minutes, raise the grain temperature to 168°F/76°C to halt enzyme activity and lock in your fermentability profile. Add boiling water to the cooler to hit this temperature, or if you have a kettle mash tun, apply direct heat. Then run off the first quart or two of wort back through the grain bed (vorlauf), the first runnings are cloudy with husk particles and grain flour. Recirculate until the wort runs clear before collecting into your kettle.
Step 4: Sparge
Sparging rinses residual sugars from the grain bed. The two main methods:
- Batch sparge, drain all the first runnings into the kettle, add sparge water at 168°F/76°C, stir, let rest 10 minutes, drain again. Two drains total. Simple and effective; most homebrewers use this.
- Fly sparge, slowly trickle hot water over the grain bed while simultaneously draining at the same rate, maintaining 1–2 inches of water above the grain bed throughout. More efficient but requires matched flow rates and more attention.
Don’t sparge with water above 170°F/77°C, above this temperature you extract tannins from grain husks, adding astringency to the finished beer. Stop collecting wort when the runoff gravity drops below 1.010 or the volume target is reached.
Step 5: Boil, hop additions, and chill
The boil is identical to extract brewing. Bring the full wort volume to a rolling boil, add bittering hops at 60 minutes, flavor hops at 15 minutes, and aroma hops at flame-out or during a whirlpool rest. Boil for 60 minutes minimum; 90 minutes for Pilsners and other lager-style beers to drive off DMS (a cooked-corn precursor that forms from SMM in pale lager malt).
After boiling, chill to 65°F/18°C for ale yeast as quickly as possible. With an immersion chiller and cold tap water this takes 15–20 minutes. Transfer to the fermenter, oxygenate well by shaking or splashing, take a gravity reading, and pitch yeast.
Step 6: Check your efficiency
Mash efficiency tells you how much of the theoretical sugar in your grain bill you actually extracted. Measure pre-boil gravity and volume, calculate the total gravity points, and compare to what the grain bill predicted. Most homebrewers achieve 65–80% efficiency when starting out. Common culprits for low efficiency: under-crushing, mash temperature too high (denatures enzymes faster), insufficient mash time, or inadequate stirring.
Don’t chase 90%+ efficiency early on, it requires finer crush and more careful technique, and the benefit of an extra 5% efficiency is about 0.2–0.3% ABV in the finished beer. Consistent technique in the 70–75% range is worth more than sporadic high-efficiency runs that don’t teach you anything repeatable.
Step 7: Water chemistry, the lever most all-grain brewers ignore too long
With extract brewing, water chemistry is largely irrelevant, the extract came from water that already shaped its character. With all-grain, your local water profile directly affects mash pH, enzyme activity, and final beer flavor. The two most impactful minerals: calcium (50–150 ppm) for enzyme activity and yeast health, and sulfate vs. chloride ratio for flavor perception (high sulfate emphasizes hop dryness; high chloride emphasizes malt roundness).
Start by targeting mash pH of 5.2–5.4. Distilled or RO water plus a small addition of gypsum (calcium sulfate) gets most pale ales and IPAs there. Brewer’s Friend’s water chemistry calculator handles the arithmetic once you know your source water’s mineral profile.
Common Questions
Is all-grain beer noticeably better than extract?
For most styles, a well-executed extract batch is indistinguishable from all-grain in blind tasting. The real advantage of all-grain is flexibility, you can brew styles that extract can’t replicate (very light lagers, highly fermentable Belgian ales, complex grain bill combinations) and you have full control over freshness. If you’re satisfied with your extract beers, there’s no urgency to switch. If you want to brew a Czech Pilsner or a session IPA with specific attenuation, all-grain opens those doors.
What’s BIAB and is it real all-grain brewing?
Brew-in-a-bag (BIAB) mashes grain in a fine mesh bag suspended in the kettle, then lifts the bag out rather than lautering through a grain bed. The result is the same, mashed wort with the same fermentable sugar profile, at lower equipment cost (no separate mash tun needed). Efficiencies are slightly lower (60–70% typically vs. 70–80% for a three-vessel system), but BIAB is absolutely real all-grain brewing and many excellent homebrewers use it exclusively.
My mash temperature dropped 10°F during the rest. Did I ruin the batch?
Probably not. A 10°F temperature drop over 60 minutes means you spent most of the mash in the correct range. The enzymes do most of their work in the first 20–30 minutes; a drift after that has limited impact. A batch mashed at 148°F that drops to 140°F will be slightly less fermentable than intended (some beta-amylase activity continues below 145°F), but the difference in the finished beer is minor. For your next batch, preheat the mash tun with boiling water before adding grain, it significantly reduces temperature loss.
