Ingredients Deep Dive

Fermentables, hops, yeast, adjuncts — ingredient science, quality, storage, and how to model choices in Brewfather

Fermentables

Fermentables are any ingredient that contributes sugars for yeast to ferment, including malted grain, malt extract, adjunct grains, and refined sugars.

Base Malts

Base malts form the majority of the grist and supply most of the fermentable sugars, enzymes, and body-building dextrins. They are fully modified (enzymatic content intact) and require mashing.

Malt	Typical Color	Key Character
Pilsner malt	1.5–2 °L / 3–4 EBC	Lightest; mild, grainy-sweet; use for lagers and pale ales
Pale malt (2-row)	1.8–2.5 °L / 4–5 EBC	Versatile North American base; neutral, clean
Maris Otter	3–4 °L / 6–8 EBC	Classic English base; biscuit, bread crust notes
Vienna malt	3–4 °L / 6–8 EBC	Light toasty, slightly sweet; used in Vienna lagers, Märzen
Munich malt	6–9 °L / 12–18 EBC	Rich malt, bread, honey; can be up to 100% in Bocks

Pilsner malt is the lightest and most enzyme-rich. It contains SMM (S-methylmethionine), a DMS precursor — a vigorous, uncovered boil is essential when using significant Pilsner malt ratios.

Specialty Malts

Specialty malts contribute color, flavor, and body without requiring active enzyme conversion. They are added to the grist but rely on base malt enzymes for any remaining starch conversion.

Crystal/Caramel Malts (15–150 °L): Kilned in their wet state, which converts internal starch to sugars and caramelizes them inside the husk. They contain both fermentable sugars and dextrins, adding body and residual sweetness. Use 5–20% of grist weight depending on style; excessive amounts can become cloying.

Roasted Malts (200–600+ °L): Roasted at high temperatures to develop color and flavors from light toast through dark chocolate to coffee/bitter char. These malts have no meaningful enzymatic activity and contribute limited fermentable extract compared with base malt.

Type	Approx Color	Character
Biscuit/Victory malt	25–30 °L	Biscuit, toasted bread
Crystal 40	40 °L	Caramel, toffee
Crystal 80	80 °L	Dark caramel, raisin
Chocolate malt	350–400 °L	Dark chocolate, coffee
Roasted Barley	500–600 °L	Dry roast, espresso, char
Black Patent	500–600 °L	Very dark color, harsh at >5%

Acidulated Malt: Contains lactic acid (1–3%); used at 1–5% of the grist to lower mash pH without liquid acids.

Wheat Malt: High protein content improves head retention and haze; commonly 40–60% of grist in Hefeweizen; 10–20% in NEIPA for haze and body.

Malt Extract

Malt extract is concentrated wort in syrup (LME) or dry powder (DME) form. It is pre-mashed and provides a convenient way to brew without lautering equipment. Color and fermentability are fixed at production. Dry malt extract has better shelf stability than liquid. Extract can darken with age due to Maillard reactions.

Adjuncts

Adjuncts are non-malt fermentable additions used to lighten body, raise gravity, or add specific flavors:

• Corn/Maize (flaked or grits): Lightens body and color; requires gelatinization or comes pre-gelatinized in flaked form.

• Rice (flaked): Very neutral; lightens body and color.

• Oats (flaked or malted): Adds silky body and increases haze; common in Oatmeal Stout and NEIPA.

• Table sugar / sucrose: Fully fermentable; dries out the beer and increases ABV with no body contribution. Useful in Belgian Strong Ales (up to 20% grist) and session IPAs.

• Honey: Typically highly fermentable (~90–95% of sugars ferment), which raises ABV while lightening body. It contributes more aroma when added late (flameout or fermentation); long boiling drives off volatile aromatics.

• Lactose (milk sugar): Non-fermentable disaccharide; adds sweetness and body to Milk Stouts, Pastry Stouts, and some NEIPAs. Typical rate: roughly 100–500 g per 20 L depending on desired sweetness.

Quality and Storage

• Malt absorbs moisture: Store in sealed containers away from humidity. Crushed malt stales within 1–2 weeks.

• Color and extract values drift with age: Use malt within its best-by date.

• Whole vs. pre-crushed: Whole uncrushed grain stores far better. Crush no more than 1–2 days before brewing.

---

Brewfather Tip: Fermentables

Build your custom fermentable library before designing recipes. Brewfather ships with a broad ingredient database, but grain characteristics (color, FG contribution, moisture) vary by maltster and lot. In Inventory → Fermentables:

• Adjust the °L or EBC color value to match your actual malt spec sheet.

• Set the Type correctly (Base, Crystal, Roasted, Adjunct) — the water calculator uses grain type to estimate mash pH contribution.

• Track stock via inventory so the recipe designer warns you when you're running low.

In the Recipe Designer, Brewfather calculates OG contribution from each fermentable using your equipment profile's brewhouse efficiency. Keep ingredient metadata (yield, color, and type) accurate so recipe predictions and water pH estimates stay reliable.

---

Hops

Hops contribute bitterness, flavor, and aroma depending on when they are added in the process.

Alpha Acids and Bitterness

Hop alpha acids (primarily humulone and cohumulone) are largely insoluble and tasteless in raw hop form. Sustained boiling isomerizes them into iso-alpha acids, which are soluble and bitter.

Utilization — the percentage of alpha acids that isomerize — depends on:

• Boil time: Longer boil = higher utilization; most isomerization occurs in the first 60 minutes, with diminishing returns beyond that.

• Wort gravity: Higher-gravity wort reduces utilization (denser wort inhibits isomerization).

• Hop form: Pellets achieve ~10% higher utilization than whole cones due to increased surface area.

• Whirlpool temperature: At 79–88 °C (174–190 °F) iso-alpha acid extraction still occurs; Brewfather models this as a separate utilization factor.

IBU calculation: Brewfather uses the Tinseth model by default, accounting for gravity and boil time. IBU values are estimates — calibrate against your actual perception.

Addition Timing

Addition Timing	Primary Purpose	Notes
60+ min	Bitterness	Aroma largely boils off
15–20 min	Flavor + some bitterness	Some aroma retained
5–10 min / Flameout	Aroma, some flavor	Minimal bitterness
Whirlpool / Hop stand	Aroma, smooth bitterness	79–88 °C for 15–30 min
Dry Hopping	Primarily aroma	Added post-fermentation; can also add some perceived bitterness via humulinones/polyphenols

Dry hopping is the most effective technique for intense hop aroma in finished beer because volatile aromatic compounds (myrcene, linalool, geraniol, etc.) are not cooked off. Best practice:

• Add dry hops at or near end of primary fermentation (most yeast biotransformation occurs during active fermentation).

• Temperature: 16–21 °C (60–70 °F) is typical; cold-side dry hopping (post-crash) preserves different aromatic compounds.

• Contact time: 2–5 days is generally sufficient; extended contact (>7 days) risks grassy/vegetal notes.

Alpha Acid and Storage

Hops degrade with age through oxidation of alpha and beta acids. The Hop Storage Index (HSI) describes this:

• Store hops sealed, vacuum-packed, below −10 °C (14 °F) in the freezer.

• Whole hops degrade faster than pellets.

• After opening, reseal and use within a few days for aroma additions.

• Hop alpha acid percentage printed on packaging assumes proper cold storage. Use Brewfather's Hop Freshness Tool to estimate actual alpha acid content based on storage conditions.

Brewfather Tip: Hops

Use the Hop Freshness Tool before brewing with hops that have been open or stored for more than a few months. In Tools → Hop Freshness, enter the original alpha acid %, storage temperature, and storage time. The tool calculates the estimated current alpha acid percentage using the Garetz degradation model. Update your hop entry in the recipe designer with the corrected value to get more accurate IBU predictions.

For whirlpool hop additions, make sure your Equipment Profile has the whirlpool utilization setting configured (typically 20–40% utilization at ~80 °C). This prevents the recipe from underestimating bitterness from large flameout/whirlpool additions, which is particularly important for NEIPA and Hazy IPAs.

---

Yeast

Yeast drives fermentation and is the primary source of fermentation-derived flavors — esters, phenols, and fusel alcohols.

Ale vs. Lager Yeast

Feature	Ale Yeast (S. cerevisiae)	Lager Yeast (S. pastorianus)
Fermentation temperature	16–24 °C (61–75 °F)	7–14 °C (45–57 °F)
Typical attenuation	72–82%	75–82%
Flocculation	Low–High (strain-dependent)	Medium–High
Flavor profile	Esters, sometimes phenols	Clean, neutral
Conditioning requirement	Days–weeks	Weeks–months

Pitch Rate

Underpitching is one of the most common causes of off-flavors and fermentation problems. Recommended pitch rates:

Beer Type	Cells/mL/°P
Ale	0.75 × 10⁶
Hybrid/Warm Lager	1.0 × 10⁶
Lager	1.5–2.0 × 10⁶

Example: A 20 L batch at 1.060 OG (14.7 °P) for an ale requires approximately: 0.75 × 10⁶ × 20,000 mL × 14.7 = 220 billion cells

Dry yeast packs vary by manufacturer and pack size, but often provide enough cells for a standard-strength 20 L ale batch when fresh and properly handled. A standard liquid yeast vial or smack pack is typically ~100 billion cells at packaging (declining with age). Starters are strongly recommended for high-gravity batches or older liquid yeast.

Fermentation Temperature and Flavors

Temperature is the primary lever for controlling yeast-derived flavors:

• Esters (fruity; e.g., isoamyl acetate = banana, ethyl acetate = solvent) increase with higher fermentation temperatures and underpitching.

• Fusel alcohols (harsh, warming) increase at temperatures above a strain's upper range or from underpitching.

• Diacetyl (buttery/butterscotch) is a normal fermentation byproduct that yeast will reabsorb given adequate time and temperature. A diacetyl rest (raising temperature 2–4 °C in the final days of fermentation) accelerates cleanup. Attenuation should be near complete before crashing.

Flocculation and Clarity

High-flocculation yeast strains (for example many English ale strains such as WY1968/WLP002) drop clear naturally; lower-flocculation strains (e.g., Hefeweizen, many Belgian strains) remain hazy longer. Cold crashing — rapidly dropping temperature to 0–4 °C (32–39 °F) for 24–48 hours — dramatically accelerates settling in most strains.

Yeast Health and Viability

• Yeast cell viability decreases with refrigerator storage (a common planning estimate for liquid yeast is roughly 15–25% loss per month, strain- and packaging-dependent).

• Always check the manufacture or packaging date for liquid yeast.

• Healthy yeast produce far fewer off-flavors and complete fermentation more reliably.

Brewfather Tip: Yeast

Use the Yeast Calculator to confirm your pitch rate before brew day. In Tools → Yeast Calculator, enter your batch volume, OG, yeast type (ale/lager), and the production date and cell count for your yeast. The calculator shows whether you need a starter and estimates starter volume to reach target cell count.

In the Fermentation Profile, set proper temperature steps including a diacetyl rest for lager strains and ale strains prone to diacetyl production (particularly English and Belgian strains). Brewfather's fermentation tracking graphs help you spot gravity stalls that may indicate underpitching or temperature issues.

---

Water

Water is the largest single ingredient by volume. Its mineral composition directly affects mash pH, enzyme activity, hop perception, malt character, and yeast health. Even a brief water chemistry adjustment — primarily targeting mash pH and calcium level — meaningfully improves beer quality.

For a full treatment of water chemistry, see Water Chemistry.

Minimum starting point:

• Calcium (Ca²⁺) > 50 ppm: Supports enzyme activity, yeast health, and promotes precipitation of proteins and oxalates.

• Mash pH 5.2–5.6: Optimal for amylase enzymes, wort flavor, and yeast.

---

Adjuncts — Flavor and Process Additions

Beyond fermentable adjuncts, several ingredients serve flavor, process, or stability purposes:

Ingredient	Purpose	Typical Usage
Gypsum (CaSO₄)	Adds Ca²⁺ and SO₄²⁻; enhances hop crispness	Water chemistry adjustment
Calcium Chloride (CaCl₂)	Adds Ca²⁺ and Cl⁻; enhances malt roundness	Water chemistry adjustment
Irish Moss / Whirlfloc	Protein flocculant; improves hot break and clarity	1 tablet or ½ tsp per 20 L, last 15 min of boil
Yeast Nutrient	Provides zinc, nitrogen, vitamins for yeast	High-gravity or adjunct-heavy beers
Lactic Acid	pH adjustment	Water and wort pH control
Coriander Seed	Flavor spice; citrus, pepper	Witbier: 10–30 g per 20 L, last 5 min
Orange Peel	Flavor; bitter or sweet	Witbier, Belgian Saison
Vanilla Bean	Sweetness, aromatic complexity	Post-fermentation; 1–3 beans per 20 L
Oak (cubes/spirals)	Tannin, wood character	Secondary conditioning; 2–4 weeks
Fruit Additions	Flavor, color, fermentable sugars	Primary or secondary; after peak fermentation

Clarity agents like Irish Moss and Whirlfloc are among the most cost-effective improvements a brewer can make — consistent use noticeably reduces chill haze and improves cold crashing results.

Brewfather Tip: Miscellaneous Ingredients

Log all miscellaneous ingredients in the Misc section of your recipe even if they are not fermentable. This ensures your brew sheet is complete and your batch records accurately reflect what was used. Brewfather's Miscs inventory tracks items like fining agents, acids, yeast nutrients, and flavor additions. Set up stock quantities so the planning screen flags when you need to replenish before a brew day.

---

Sources

• Palmer, John J. How to Brew, 4th ed. Brewers Publications, 2017. (Chapters 3–6: malts, hops, yeast, adjuncts)

• White, Chris, and Jamil Zainasheff. Yeast: The Practical Guide to Beer Fermentation. Brewers Publications, 2010. (Pitch rate, fermentation temperature, diacetyl)

• Hieronymus, Stan. For the Love of Hops. Brewers Publications, 2012. (Alpha acids, dry hopping, utilization)

• Maye, John Paul, Robert Smith, and Jeremy Leker. "Humulinone Formation in Hops and Hop Pellets and Its Implications for Dry Hopped Beers." MBAA Technical Quarterly 53.1 (2016). (Dry-hop bitterness contribution from humulinones)

• Briggs, D.E., et al. Brewing: Science and Practice. Woodhead Publishing / CRC Press, 2004. (Malt modification, specialty malt chemistry)

• Garetz, Mark. Using Hops. HopTech, 1994. (Hop storage degradation model)

• Daniels, Ray. Designing Great Beers. Brewers Publications, 1996. (Crystal malt usage, specialty grain guidelines)

• Noonan, Gregory J. New Brewing Lager Beer. Brewers Publications, 1996. (Lager yeast pitch rates, conditioning)