When it comes to brewing, besides perfect sanitisation the other deciding factor is temperature. If your equipment is sanitised correctly, from the pot you boil in to the spoon you stir the mixture with the only thing you have to contend with is the temperature of your wort (especially during the initial fermentation stage).
Depending on the style of beer you are making, your temperature will vary. One of the biggest problems I have as a homebrewer is cooling down the hot wort mixture before pitching my yeast.
Sure, I could put 20 litres of water into the fridge and let it cool overnight. But if you are like me, you’re a hobby brewer and if you don’t have a dedicated spare fridge lying about for brewing, you have just a standard fridge in your kitchen most likely with shelves and filled with food, condiments and drinks.
If you live somewhere cold and brew in the winter, you probably have the opposite problem where your tap water is cold. But because I live in a tropical climate (Queensland, Australia) even our winters can be laughably warm.
I don’t have the luxury of space in my fridge for cooling large amounts of water. I also don’t have the money or setup for an immersion chiller or any other cooler type setup to cool down my wort quickly. In Australia we also are susceptible to drought, so being smart with water is always wise.
I could also fill up my bathtub with ice, but the thought of going out and buying potentially 10 or so bags of ice seems like an unnecessary expense (probably around $30-$40).
So that leaves natural open-air cooling also commonly known as no chill brewing. Except, I wouldn’t dare open air ferment myself personally.
There is a lot of misinformation out there on no chill brewing. Some people are completely against the idea of letting your wort to sit before pitching the yeast and some see no issue with it as long as your sanitisation is good. So which is it?
We only have to look back to the old days of brewing (the early nineteen hundreds and even earlier), sanitisation was more relaxed and all fermentation took place in a vessel called a coolship (authentically known as a koelschip). A coolship is a large, open-top vessel where your wort cools. The size of it is generally large to allow for faster cooling.
One such brewery that uses an open-top fermentation approach like this is Anchor Brewing Company in San Francisco. While Anchor use fermentation tanks, the principle remains the same. They don’t cover their fermenting brews and if you have ever tried one of their beers, you’ll definitely taste the quality and no ill-effects of open-top fermentation.
While breweries like Anchor open-top ferment, they still cool their wort down first. They don’t let it overnight to naturally cool. So play it smart and cover your wort as it cools. If you drop yeast into infected wort, it will just turn out nasty.
The last two homebrews that I did I let my wort sit overnight and because my sanitisation was exceptional I had no issues. It also allowed me to get a nice yeast starter happening as well in advance, I always put a little extra yeast in just to be safe.
When no chill cooling your wort, always make sure you put it into your fermenting vessel and put the lid on to prevent contaminants getting in.
I personally put the wort right into the fermenting vessel, put the lid on and let it sit for at least 24 hours to cool down before putting the yeast in. Because my vessel is sanitised, I am not concerned about infection.
After you pour the wort into your fermenting vessel quickly put the lid on and then roll it on its side and make sure the wort touches all parts inside to sanitise it. That’s it.
If you are worried about contamination, take a small sample of the wort and put it into a jar and cover it with aluminum foil. Sit it near where your fermenting vessel will live and keep an eye of it.
Worthy of note is that using the no chill method will add in a variable to your brewing called hop utilisation. Essentially it means your hop additions will go for longer when you add them late into the boil.
When using no chill I usually throw my 20 minute hop additions in at the end of the boil or with two minutes to spare knowing they’ll continue to impart bitterness as the wort remains hotter for longer.
If your brew is going to become infected, your sample will show signs of growth. Never throw away a brew just because the wort cooled naturally and you’ve read that it means your beer will fail.
Excellent write up. I agree 100% that chilling wort is not necessary as long as the fermenting vessel is properly sanitized and immediately closed off to prevent airborn bacteria’s getting into the wort and vessel.
Been brewing since 2005 using 15 gallon keg as kettle. Initially used wort chiller to cool wort but hate wasting water (and also exposing the wort to the air that happens using immersion chillers) so tried letting beer cool overnight in the covered kettle (using aluminum foil to seal the top).
Been no-chill brewing since 2006 and have never had a bad batch. In fact, pretty much everyone who has tried my beer raves about the flavor. Also I have won best in class in brewing competition. I brew about 200 gallons a year.
Besides saving water, it allows me to fill the kettle to the top since no wort is displaced because no chiller is immersed in it, so brew yield is maximized. Surely there are downsides, but I think the positives outweigh the negatives.
One thing to note is you shouldn’t aerate your wort until it is cooled (oxygen is bad for the wort at high temps), so you probably shouldn’t transfer it to another container until it’s cooled. I have a valve on bottom of kettle that I use to transfer the cooled wort to carboys which I shake to help aerate as they’re being filled.
I kind of doubt brewers in the old days chilled their wort nor had as good of sanitation techniques as today, yet beer was still drinkable then.
If you want to save water and increase your brew yield, try the no-chill method. You probably will be pleasantly surprised.
i love the fact that in this and age we worry about how to cool a wort……ah the beauty of home brew…..keep it simple have a home brew…..no worries…but think about the magic and results by experimenting with how to cool down your……
Question, I sanitize my equipment, incl. my Fermenters with Iodophore and then rinse it with boiling hot water. Is that sufficient? Why are you guys so concerned about sterilizing the Fermenter, the boiling hot wort will kill off any bacteria inside the wort, or not?