Homebrewing is an enjoyable process but chilling the wort to the right temperature is one of the hardest things for homebrewers, especially beginners.
Most beginners whose first batch is in the making realize that chilling wort is a tough process when it is already too late and they start to panic while they attempt all ways that come to their minds to chill it, including fast typing in the Google search bar for miraculous help.
If you are about to brew your first batch then this post will be perfect for you. I wished that I had written this article for myself in the past before I brewed my first batch but unfortunately, I had to learn it the hard way.
Why is it important to chill the wort quickly?
Cooling the wort to a yeast-ready temperature is important because the sooner you pitch yeast, the lesser the odds of bacteria or wild yeast activating within the fermenter.
Yeast colonies will battle possible infections, but only if you pitch it in time. Once the wort is chilled, it no longer has a defense against germs and other nasty stuff.
As the wort cools down it will at one moment be too warm for pitching yeast but ideal for hosting bacteria and some wild yeast that could survive, so getting it from hot to room temperature ASAP is recommended.
So, pitch the yeast as soon as you can, once it’s properly chilled, but do not hurry or you’ll pitch it too soon!
As you’ll see in this article, I often use an overnight method which takes quite a long time and I manage to brew fine beer. Thus, it doesn’t mean that if you don’t chill the wort quickly it will be ruined, it just increases the odds.
1. Cooling wort with ice
Prepare lots of ice before the brewing day and you will have an easier time cooling the wort to ideal temperatures.
On my first brewing day, I forgot to make the ice and it took me 10 hours to cool it with cold water, hopefully, it was a chilly evening that helped hasten the process.
Remember that you need lots of ice because when the wort is hot it will warm the outside water temperature quite easily, so unless there is lots of ice (and I mean lots of ice) you will end up with warm water in a matter of minutes which won’t help to cool the wort at all.
Place the wort somewhere where you can circulate the water and where you can add lots of ice around it.
The ideal place is a kitchen sink because it is big enough for pots and fermenters to fit but it is small enough so you can keep the water and ice on the right level.
A bath, for example, is a terrible choice because you won’t be able to sink the fermenter or pot in it and the temperature from the cold water and ice won’t be focused, so you will spend tons of water and ice while the majority will be wasted.
Remember that it is important to circulate the water so if the wort is really hot and it warms the outside water you will have to quickly get rid of it and pour cold water and add new ice if it melts.
With a gallon of ice, you will have to repeat this process a few times if you do not have space to fit all the ice immediately.
However, this is among the best methods for beginners who do not have chillers.
2. Cooling with a cold-water circulator (chiller)
A chiller is an amazing tool that can be expensive for beginners but is certainly worth the price it comes with.
A chiller lets the cold water flow through a tube that is inserted within the wort. This way it ensures there’s only cold water circulating while it removes the warmed water through the other end.
It’s like a garden hose, so you’ll need to connect it to an available pipe and ensure the water can leave somewhere.
This is the fastest way to chill the wort, but you don’t need it immediately and can rather get it after a few batches if you find other methods too painful.
You can grab chillers on Amazon if you are looking for the most efficient way of cooling wort.
Chillers are probably the most useful optional gear for homebrewing as they make a tremendous difference when it comes to brewing, especially for those who brew more than once in a while.
3. Cooling wort overnight
You can simply let your wort chill outside during winters and colder autumn weeks overnight and tomorrow when you wake up it will be ready. The temperature below 50°F (10°C) will be super efficient in chilling the wort overnight, but leaving a fermenter at room temperature will also be useful, just a bit slower.
It will take quite some time to cool wort this way, and you can expect up to 8 hours to chill it using the overnight method, or a few hours less if it’s noticeably colder outside.
As a beginner, this method works quite well because you can brew the wort, place it in a fermenter, seal it, and let it stay outside before you pitch the yeast the next day.
However, ensure that it’s perfectly sealed, so nothing can get in, keep it out from the sun, and do not let it stay outside more than needed once it’s chilled.
4. Adding pre-chilled water
This method is golden for anyone who uses extracts for their beer and many beginners brew with extracts (kits) for the first time just like I did for my first beer batch.
However, this method is unusable if you brew all grains.
When you brew with extract you have to warm the extract can for a couple of minutes in hot water, then you pour a few liters of hot water into a fermenter or a pot and pour the entire extract from the can into it.
After that, you add sugar and stir until everything comes in place, and then you continue to add the rest of the water to achieve the wanted amount of the wort.
In this last process, I used to add the hot, boiling water which might seem unnecessary because you could easily add cold water and you would have a perfect temperature to immediately pitch the yeast in the fermenter.
Yet, adding unboiled, uncleared water to a wort should not be practiced because it can contain bacteria and chlorine which can spoil the beer. Moreover, if the water is not purified and has lots of dirt in it, that taste will be present in the beer even if it survives the infection.
NEVER USE WATER that has not been purged and you will thank me once you realize that you’ve been making great beer for years, while those with a lazy approach either end up with bad or destroyed beer.
You should boil the water to 212°F (100°C) because no bacteria can live at this point and the water is purified. After that, you should seal the opening so nothing can fall in and let it chill the day before in a sanitized environment.
If you do this step in the morning or the day before you will have perfectly chilled water that’s been purified for brewing with extracts and you will be able to immediately pitch the yeast.
If you believe your water is clean and safe straight out of the pipe, by risking you’ll save time, but I do not encourage it!
The issues you may encounter while chilling wort
1. Water consumption
Water consumption is a real problem in home brewing, but it’s a sacrifice you need to make for good beer.
The water that goes in the recipe is nothing compared to the water used for chilling the wort, so you can expect to spend 5 to 10 times more water for chilling purposes.
I like to use that water for my plants in the garden, so find its purpose, just try not to waste it. If you can think of another great way how to repurpose the water, I’d like to hear about it!
2. It takes time
Unless you use the ice or chiller method, it will take you up to 8 hours to chill the wort even during autumn or weaker winters. Spring and summer are a bad time for chilling outside, so prepare a chiller, lots of ice, a fridge, or something!
The good news is that with a proven method like using a chiller, you can cool the wort within 30 minutes.
3. How to know when wort has cooled to the desired temperature
You should be patient, so the wort can cool down. However, it’s hard to know the temperature without checking it with a thermometer.
This is the only correct way unless you have lots of experience already and can tell the temperature based on many successfully chilled worts.
However, you’ll have to sanitize the thermometer each time you check the temperature. I personally, find it annoying, so instead of using a classic thermometer, I bought a sticker thermometer that you can place on the outer wall of your fermenter.
You can easily tell what is the temperature inside without opening the seal, so that’s a great way to check the temperature.
At what temperature can you pitch yeast to the wort?
Most yeast is killed at temperatures over 89.6°F (32°C), so before you can avoid damage to the yeast the temperature needs to be at least lower than that.
Therefore, never pitch yeast before you are in the right temperature range and that range begins with the upper-temperature point at which the yeast should ferment. However, this is only the warmest it can be without serious consequences. You should still get it lower than this point before you pitch it to be completely sure.
In conclusion, the temperature at which you should pitch the yeast is simply the temperature at which you plan to ferment it or as close to it. If you ferment your beer at 68°F (20°C), do not pitch it before the temperature is at least below 73.4°F (23°C).
I like to get to the optimal range I can get before pitching the yeast, so I always wait for the lowest temperature degree because the yeast will internally warm up the wort when it begins to ferment for up to 5 degrees.
Now if you add it on a higher temperature spectrum it can easily warm up over the allowed range and damage your beer.
What can go wrong if you pitch yeast too early?
If you pitch yeast too early while the wort is too hot, you will either completely kill your yeast or reduce its numbers and make it less effective due to yeast stress.
Moreover, each yeast type has its range at which it should ferment, and failing to keep the fermentation within the range will result in an unwanted taste.
Even though the yeast may survive, you won’t be happy with the final flavors it will produce if it is pitched too early!
So, if you are impatient, work on this virtue as it can mean a difference between healthy and failed fermentation.