Brew this month

Brewing chemicals, water salts and finings

Water salts, acids, Whirlfloc and finings, Campden tablets, sorbate, enzymes and antifoam, explained by what each does and used per the label.

Brewing water chemistryWhirlfloc vs Irish mossCampden vs sorbateFinings explainedWater chemistry calculator
Hands holding a pen-style digital pH meter next to calibration solutions
Photo: Tawaye, CC BY-SA 4.0, via Wikimedia Commons
Narrow by situation57 products
Brewing water chemistry calculatorSalt additions to ppm, SO4:Cl and residual alkalinity.
Chemicals: label directions onlyUse sanitizers, cleaners, acids and salts only at the dilution and contact time on the label. Wear eye protection with acids and powders, add acid to water, keep them away from children and food prep. Star San is EPA-registered (Reg. No. 65001-1) as a no-rinse sanitizer at label dilution.Source: EPA Star San label
Sulfites and sensitive guestsCampden tablets and potassium metabisulfite add sulfites. Commercial wine at 10 ppm or more must say “Contains sulfites”; home wine is not labeled, so tell sulfite-sensitive guests (often people with asthma).Source: TTB: sulfite declaration

What brewing chemicals do you actually need?

Most extract brewers need almost nothing from this aisle beyond a kettle fining such as Whirlfloc. All-grain brewers add water salts and an acid; wine, cider and mead makers add Campden tablets, sorbate and pectic enzyme. Each product below is used at the dose on its own label, never a guessed one.

What each group does

GroupExamplesWhat it does
Water saltsGypsum, calcium chloride, chalkAdjust calcium, sulfate, chloride and alkalinity
AcidsLactic 88%, citric, tartaric, malicLower mash pH; adjust wine and cider acidity
Kettle finingsWhirlfloc, Irish mossDrop proteins late in the boil
Post-ferment finingsGelatin, Biofine Clear, kieselsol + chitosan, bentoniteClear yeast and haze
StabilizersCampden tablets, K-meta, potassium sorbateSulfite protects; sorbate stops refermentation only with sulfite
Enzymes and aidsPectic enzyme, amylase, Fermcap-SPectin haze, starch conversion, foam control

Source: Product labels and research.md §2.9 sources

Water salts: ppm per gram

One gram of a salt in one US gallon adds a fixed amount of each ion. Gypsum pushes sulfate (crisper bitterness); calcium chloride pushes chloride (rounder malt). Chalk barely dissolves in plain water, so real additions fall short of the table.

What 1 gram of each salt adds to 1 US gallon (ppm)

SaltCaMgNaSO4ClHCO3
Gypsum CaSO4·2H2O61.5——147.4——
Calcium chloride CaCl2·2H2O72———127.4—
Epsom salt MgSO4·7H2O—26.1—103——
Baking soda NaHCO3——72.3——191.9
Table salt (non-iodized) NaCl——103.9—160.3—
Chalk CaCO3
Poorly soluble in plain water; real additions dissolve only partly		105.8————CO3 158.4

RA = Alkalinity − (Ca / 3.5 + Mg / 7) (all ppm; alkalinity as CaCO3 = HCO3 × 50/61). One Campden tablet treats about 20 gal (75 L) of chloraminated water (AHA/BYO guidance; check your tablet's label). Sources: Palmer & Kaminski, Water: A Comprehensive Guide for Brewers (Brewers Publications); BYO: Charts & calculators (brew-water spreadsheet); Craft Beer & Brewing: Brewing tools (water chemistry). Gypsum and calcium chloride are checked against published calculators; the rest are stoichiometric values.

Brewing water chemistry calculatorSalt additions to ppm, sulfate-to-chloride ratio and residual alkalinity.

Finings, stabilizers and label notes

Gelatin and chitosan are animal-derived, so they are not vegan, and chitosan is a shellfish allergen concern. Campden tablets and potassium metabisulfite add sulfites. Pectic enzyme clears fruit haze but can slightly raise methanol; normal home wine and cider still do not reach dangerous levels.

Safe handling of brewing chemicals

  • Use the label's dose and contact time only; never an off-label amount.
  • Wear eye protection and gloves with concentrated acids and fine powders, and add acid to water, not water to acid.
  • Store chemicals away from children, pets and food prep, in their original labeled containers.
  • Tell guests when a wine or cider contains sulfites; sensitive people are often asthmatic.

Not sure where to start? Extract brewers rarely need salts at all; treat chloramine and add finings only if you want clearer beer.

Related reading: best brewing sanitizers and cleaners and best pH meters for brewing.

Read before you buy

Best of

Best pH meters for brewing: mash, wine and kombucha

The best pH meter for brewing compared by stated accuracy, ATC, calibration and probe type, plus when cheaper test…

Versus

Whirlfloc vs Irish moss (and other finings) for clear beer

Whirlfloc vs Irish moss: what each kettle fining does, label doses and timing, plus gelatin, Biofine and…

Versus

Campden tablets vs potassium sorbate: what each one does

Campden tablets vs potassium sorbate: sulfite protects against microbes and oxidation, sorbate stops new yeast growth.…

Guide

Cleaning vs sanitizing brewing gear

Cleaning vs sanitizing brewing gear: why you need both, which products do which job (PBW, OneStep, Star San,…

Guide

Brewing water chemistry for beginners

Brewing water chemistry for beginners: read a water report, remove chlorine and chloramine, use gypsum and calcium…

Guide

Mash pH and how to adjust it

Mash pH for all-grain brewers: the 5.2–5.6 target, how to measure with a calibrated meter, and how to lower it with…

Brewing chemicals & water: questions

Do I need water salts for extract brewing?
Usually not. Malt extract already carries minerals from the maltster's water. Water salts matter most for all-grain mashes; use the water chemistry calculator with a water report.
What is Whirlfloc?
A tablet of Irish moss and carrageenan added near the end of the boil to help proteins drop out. Craft A Brew's label lists half a tablet per 5 gal at 5 minutes left; follow your package.
How many Campden tablets per gallon?
Follow the label on your tablets; potassium and sodium versions differ. Campden adds sulfites, so warn sulfite-sensitive guests. For chloramine in brewing water, one tablet treats about 20 gal (75 L) per AHA/BYO guidance.
Does potassium sorbate stop fermentation?
It prevents yeast from multiplying again, and it is meant to be used with sulfite, after fermentation has finished and the wine or cider is clear. It will not stop an active fermentation.
Are brewing finings vegan?
Not all. Gelatin and isinglass are animal-derived and chitosan comes from shellfish. Silica sol (Biofine Clear) and bentonite are mineral-based.