Sanitising fifty bottles quickly without missing any
A 20 litre batch fills about fifty 330 ml bottles. One dirty bottle is enough to spoil the impression of the whole batch. The answer is a system: clean early, sanitise in order and never let clean and dirty bottles share a crate.
Fifty bottles is where mistakes creep in
Twenty litres of beer, after losses, fills roughly 55 bottles of 330 ml or around 28 bottles of 650 ml. Somewhere around bottle thirty, attention slips. One bottle gets sanitised twice and another not at all. A bottle with a ring of old yeast at the bottom goes through because it was in the wrong crate.
That one bottle becomes the gusher or the sour one. A system takes your attention out of the job, which is exactly what you want when you are tired and the beer is waiting.
Clean on the day you drink, not the day you bottle
The real work happens weeks before bottling day. Rinse every bottle straight after you pour it: two or three good rinses with tap water, shaken hard. Dried yeast and beer residue take an overnight soak and a bottle brush to remove later. A fresh rinse takes ten seconds.
Store rinsed bottles upside down in crates so they drain and stay free of dust and insects. If a bottle has mould or a dried ring that will not shift, soak it in a brewery cleaner such as an oxygen-based cleaner or PBW and brush it out. If it still will not come clean, recycle it. A bottle is cheaper than a batch.
Sanitiser only works on clean surfaces. Our guide to cleaning versus sanitising explains why.
Choose a no-rinse sanitiser
For bottling, a no-rinse acid sanitiser such as Star San is the easiest choice. The usual dilution is about 1.6 ml per litre of water, which is 30 ml in roughly 19 litres. Follow the contact time on the label. Foam left in the bottle is harmless and does not need rinsing out.
Iodophor works too, at around 12.5 parts per million. It also needs no rinse at that strength. Avoid bleach for bottles. Any trace of chlorine left behind can react with phenols in beer to form chlorophenols, a harsh, medicinal flavour you can taste at tiny levels. Make up sanitiser with clean water. Very hard borewell water can make acid sanitisers cloudy and weaker, so packaged drinking water is safer if yours is hard.
The crate system that never misses a bottle
The key rule is that bottles only move in one direction. Set up three zones on the counter: the crate of clean, rinsed bottles on the left, the sanitiser in the middle and an empty crate or bottle tree on the right.
- Take a bottle from the left crate. Hold it up to a light. If you see residue, put it aside.
- Sanitise it: fill and empty, or give it two pumps with a bottle sprayer.
- Put it upside down on the bottle tree or in the right-hand crate.
- Never put a bottle back in the left crate.
When the left crate is empty, every bottle has been done exactly once. A bottle tree with a sprayer on top is the fastest kit for this. It costs less than a single lost batch and turns fifty bottles into about fifteen minutes of work.
Caps, bottling wand and everything else
Bottles are not the only thing that touches the beer. Sanitise the crown caps or swing-top seals by dropping them in a small bowl of sanitiser. Sanitise the bottling bucket, the tap, the tube and the bottling wand. Take the tap apart if it comes apart; residue inside a tap is a common hiding place for bacteria.
Keep a spray bottle of sanitiser on the counter for your hands, the capper and anything you put down by mistake. If you are choosing between closures, our guide to bottles and crown caps or swing tops covers the trade-offs.
Timing the whole job
With rinsed bottles and a bottle tree, the full routine runs to about an hour for a 20 litre batch:
- 10 minutes to make up sanitiser and sanitise the bucket, tubing and wand.
- 15 minutes to sanitise fifty bottles on the tree.
- 30 minutes to fill and cap.
- 5 minutes to wipe the bottles and rinse the kit.
Fill bottles soon after sanitising rather than leaving them for hours. In a humid Indian kitchen, an upturned bottle stays sanitary for a while, but dust and fruit flies arrive faster than you think.
Write the count down
Count your bottles at the start and again when capped. If 52 went onto the tree and 51 came off full, find the one you missed. It will be on the counter with sanitiser still in it, or it will be the one you knocked into the sink.
Your first step: buy or borrow a bottle tree and sprayer, then rinse every bottle you empty from tonight onwards so bottling day starts with clean glass.
Common questions
How much Star San do I use per litre?
About 1.6 ml per litre of water, or 30 ml in roughly 19 litres. Check the label for the current dilution and contact time.
Do I need to rinse no-rinse sanitiser out of bottles?
No. At the correct dilution, foam left in the bottle is harmless and does not affect the beer.
Can I use bleach to sanitise beer bottles?
It is better not to. Traces of chlorine can react with phenols in beer to form medicinal chlorophenol flavours.
How many bottles does a 20 litre batch fill?
Around 55 bottles of 330 ml or about 28 bottles of 650 ml, depending on losses.
