Which sanitiser to buy for homebrewing in India and why

Clean first, then sanitise

Sanitiser does not clean. It kills microbes on a surface that is already clean. If there is a film of dried krausen or beer stone on a fermenter, bacteria hide underneath it and the sanitiser never reaches them.

So the routine is always two steps: clean with a proper brewery cleaner or unscented washing soda and a soft cloth, rinse, then sanitise everything that touches the beer after the boil. Our guide to cleaning versus sanitising covers the cleaning half in detail.

Acid no-rinse sanitiser: our first choice

The most popular sanitiser among homebrewers worldwide is an acid-based no-rinse product made from phosphoric acid and a foaming surfactant. Star San is the best known. Indian homebrew suppliers usually stock it or an equivalent.

Why we like it:

• It works in about a minute of contact time.
• You do not need to rinse, so you do not risk recontaminating with tap water.
• Diluted correctly, its residue does not affect beer flavour or harm the yeast.
• The foam reaches into corners and tubing.

Mix it at the dilution on the label, which for the common product is about 1.5 ml per litre. Do not fear the foam. Brewers say "don't fear the foam" so often it is practically a slogan, because a few bubbles left in the fermenter are harmless.

The Indian water catch

Acid sanitisers depend on low pH. Very hard water, which is common from borewells across much of India, can raise the pH of the diluted solution and turn it cloudy. A cloudy solution may not be working.

Two fixes. Mix it with RO, distilled or packaged drinking water. Or buy cheap pH strips and check the solution: it should sit below about pH 3. Mixed in clean water and kept in a closed spray bottle, it stays usable for a long time. Dump it when it turns cloudy or the pH rises.

Iodophor

Iodophor is iodine bound to a carrier that makes it safer and less staining. Used at about 12.5 ppm, it is a no-rinse sanitiser that works in a couple of minutes. It is a good choice if you cannot find acid sanitiser.

The downsides: it can stain plastic orange over time. Using too much leaves a medicinal taste. Measure it carefully. The amber colour is a handy guide: once a mixed solution fades to pale, it has lost strength and should be replaced.

What we would avoid or use with care

• Household bleach. Cheap and effective, but it must be rinsed off thoroughly. Any chlorine left behind can react with compounds in beer to form chlorophenols, which taste of plastic or medicine at tiny concentrations. Rinsing with chlorinated tap water also undoes some of the work. We would not use it routinely.
• Potassium metabisulphite. Winemakers use it. Campden tablets are great for removing chlorine from brewing water. As a sanitiser for brewing gear it is weak and unreliable on its own.
• Peracetic acid. Commercial breweries use it widely. It is effective and breaks down cleanly, but the concentrate is corrosive and its fumes are harsh. Fine for experienced brewers with gloves, goggles and good ventilation. Not a beginner product.
• Isopropyl or ethanol sprays. Useful for spraying a valve or the outside of a yeast packet. Not practical for a whole fermenter.

Using sanitiser well

A few habits make more difference than which brand you choose:

1. Sanitise everything that touches cooled wort or beer: fermenter, lid, airlock, spoon, hydrometer, tubing, bottles and caps.
2. Respect contact time. Spraying and immediately pouring wort in does not give it time to work.
3. Never use scratchy pads on plastic. Scratches hide bacteria that no sanitiser reaches.
4. Replace old plastic tubing and buckets once they are scratched or stained.

If your beers keep turning sour, gushing or tasting of nail polish, sanitiser technique is the first suspect. Our guide on infection and bacteria in brewing helps you match the symptom to the culprit.

Good sanitation is one part of a bigger process discipline. Brewers who get it right also control fermentation temperature, pitch healthy yeast and package without oxygen. That full routine is what turns occasional good beer into consistent beer.