Welcome to another brewing tutorial by none other than ol’Big Robb himself. Today we are going to look at the important topic of how to cool wort.
Watch the following video and then dive into the post below to learn all about how to do this correctly so your beer turns out as good as it possibly can!
Ok so as you just heard me say… Cooling your wort is one of the most important steps in the brewing process; however because it is at the end of the brew day many people don’t give it as much attention as they should, which unfortunately can result in a less than top-notch beer and in some cases completely ruin your brew.
So before we get into the top 5 ways to chill your wort I am going to explain to you why you need to do it and exactly what can happen if you don’t.
Why Chill Your Wort
Reason #1: Don’t Kill the Yeast Man
Temperature control is crucial throughout the brewing process.
It is important when you are doughing in, when you are mashing, and obviously you need to get the temperature up to boiling temp to be able to boil, but than it is also important when you are pitching your yeast (which we are going to talk about), fermenting temperature is crucial as is the temperature you cold crash and bottle condition at.
Pitching your yeast is when you add your yeast or yeast slurry directly to the wort (unfermented beer). It is crucial to your future beer that the temperature of your wort be in the correct range.
If the temperature is too hot you can kill the yeast. And if the temperature is too cold you can put it to sleep.
Putting the yeast to sleep is obviously better than killing it as the yeast will waken back up as the wort temperature warms up to room temperature. However, this has dangers of its own as well; if you let the yeast sit to long without fermentation occurring it can permit bacteria to take affect which results in an infection and off flavors occurring.
So bottom line it is important to pitch the yeast at the right temperature from the get go.
For Ale yeast you will need the temperature to be in the range of 68-72 degrees F (20 – 22 degrees C). And for lagers you will want the range to be 45 – 57 degrees F (7 – 14 degrees C).
Do not worry about nailing that range down perfectly. This is make beer easy after all.
Myself personally I just shoot to get my wort chilled down under 70 degrees for ales. If I end up at between 60 – 70 degrees F I am happy and good to go.
Don’t bother trying to heat the wort back up by adding hot water or anything like that, the beer will be fine. These are all just targets to shoot for.
Reason #2: Cold Break Baby!
When you cool the wort it causes solids to be formed. This is called the cold break. When this happens the solids clump up together and drop to the bottom of the kettle.
When you transfer the wort to a fermenter than the solids stay behind in the bottom of the kettle.
This allows for a much clear and cleaner end product. Some of the methods of chilling we are going to discuss below will disrupt this process, so it is not a huge deal, so do not over think it.
Reason #3: No Corn off Flavors
Cooling your wort slows down the production of DMS. This is why it is important to cool your wort as rapidly as possible.
DMS otherwise known as Dimethly Sulfide has the smell of cooked or cream corn. It is present in most beers, but you want to minimize it as it is a definite off flavor you want to avoid.
I don’t mind having corn on the cob with my beer, but I sure don’t want my beer to taste like corn.
Reason #4: Keep the Nasties Out of Your Beer
By cooling the wort as quickly as possible and adding the yeast to get the wort into active fermentation you are reducing the chance that bacteria and other nasties can grab a hold of your homebrew and infected it.
After the wort gets under 160 degrees F (71 c) bacteria can take root in your beer and ruin it. The key is to get the temperature down quickly and add the yeast; which will drastically reduce the chance of bacteria taking effect.
OK so there you have it, the top 4 reasons to chill wort…
Now that we are clear on the fact that it is pretty important to do so, let’s dive into the best way to chill wort. We will look at 5 methods:
Method #1: Top’er Up with Cold Water.
OK so this method is if you are an extract brewer and using beer kits. If you are into all grain brewing this method is not for you.
So typically if you are brewing with an extract beer kit you have boiled the ingredients of the kit. In order to get this boiled wort down to the correct temperature to pitch the yeast you can mix the hot water with cold water.
When you are making a kit you are boiling only a fraction of the total amount of final volume you will need.
For example, you may be making a 5 gallon batch, but only boil about 3 gallons. You would top up with 2 gallons of cold water to reach the required 5 gallon size.
The cold water absorbs a lot of the heat from the boiling wort.
To do this method you will take 2 gallons of very cold water and pour it into your sanitized fermenter.
You can leave the water in the fridge in a sealed container the night before you brew in order to get it very cold. Do make sure the container with the water is very cold as the water can take on the taste of unsealed food in the fridge. (not a good thing)
After you pour the 2 gallons into the fermenter you slowly pour the 3 gallons of hot wort into the fermenter. Once you have poured it all in you need to take a sanitized spoon and stir the wort in order to mix the hot and cold liquids.
Once you are done the wort should be close to the temperature needed to pitch the yeast.
Method #2: Take an Ice Bath
You can do this in your sink if you like or even better pick up a large rubber maid container.
Fill the sink/container with ice water. Cold water filled with ice.
Put the kettle into the water with the lid on. Swirl the water in the container continuously and add more ice as the ice melts. You may need to change the water as it gets to hot also. When you are changing the water you can take a sterilized spoon and stir the wort as well.
Once the kettle is cool to the touch you can start checking the temperature of the wort to determine if it has reached the temperature you can pitch the yeast. Use a sterilized thermometer to determine the temperature.
Once the temperature is cooled to the correct temperature you can transfer it to your fermenter and add the yeast.
This method is the least expensive of the all grain methods, however it is the most time intensive.
Method #3: Don’t Worry About Chilling It
OK not quite… but close enough.
The Australians invented my favorite method of brewing called Brew in a Bag and they also developed a method of chilling the beer called “No Chill Brewing”!
I have used this method many times and I very much enjoy using it.
It is inexpensive to do, it takes no time at all and it works well.
It involves simply taking a food safe HDPE (high density polyethylene) container and pouring the hot wort into it and letting the container sit out overnight (10 – 12 hours).
At the end of the 10 -12 hours the wort is at perfect yeast pitching temperature.
No Chill brewing works well. One of the concerns I had was whether or not this method would result in more DME being produced and for whatever reason it does not. I could not detect any corn off flavors in any of my home brews I used this method on.
So here is how you No Chill:
Pick up a food safe HDPE container.
Clean and sterilize the container. Cleaning it is more important than sterilizing it as you are pouring boiling wort into it. Having said that I always leave my container sitting filled with sanitizer between brews.
Get yourself some oven mitts. While handling the HDPE container you will want the mitts on. Or you are going to end up with some toasty fingers.
Unscrew the air vent (little cap) on back of container in order to let the steam out while pouring the hot wort into the container.
Pour the hot wort into the container.
Screw the cover and air vent cover back onto the container.
Shake the container around. You want the hot wort to touch all areas of the inside of the container as this will sanitize the container.
Unscrew the air vent cover and squeeze as much air out of the container as you can, screw the air vent cover back on.
And that is it, bob is your uncle, leave the container out for 10 – 12 hours and let it chill!
One quick note, I read in other places that you can leave the no chill cube for weeks filled with wort before transferring it to the fermenter. I tried this and let it sit for about 4-5 days and that was the only time I got into trouble using this method.
Bacteria somehow got in and ruined the batch, perhaps the air vent was not screwed on tightly I do not know, but after that I never let it sit for any longer than overnight; and never had a problem.
Method #4: The Immersion Chiller
There are two ways you can use an immersion chiller. One of them wastes a ton of water and the other nowhere near the same amount of water is wasted.
#1) The traditional method of using the immersion chiller is the one that uses a ton of water. What you do is you take your immersion chiller; which is basically a metal copper coil; and you place it into the hot wort. Do so with about 5 minutes left in the boil.
There is no need to sanitize the chiller as the hot wort will do that for you. You than connect one end of the unit to your cold water source (tap) and the other end goes into the drain.
Once you have completed the boil you turn the cold water on and the cold water running through the chiller (which is submerged in the wort) chills the wort as the cold water passes through it.
With oven mitts, periodically swirl the immersion chiller around in the wort to get the wort circulating.
Also, put the cover on your wort, this does slow the cooling process down some, but it keeps bacteria from getting into your wort and spoiling it during the cooling process.
#2) The second method takes just a little bit longer, but I like it better as it does not waste anywhere near the water that the first does.
You will need a recirculating pump for this method.
Take a large bucket or rubber maid container and fill it with ice-cold water and ice. Place the immersion chiller into the ice-cold bucket.
Then connect one end of the tube connected to wort chiller to the recirculating pump and the other end of the tub put it back into the kettle so the wort is pumped back into the kettle.
Yes as you may of figured out, one of the problems is that the cold break solids are going to be circulated around and the wort will be a bit cloudier, but most of this will fall out during fermentation and if you cold crash after fermentation it will clear up just fine.
Turn on the recirculating pump and pump the wort through the chiller that is sitting in the ice-cold water. Continue to add ice to keep the water cold.
Method #5 – The Counter-Flow Chiller
This is the primary method of chilling I used at my brew pub.
Basically a counter flow chiller is a tube inside of another tube. One tube has the hot wort run through it in one direction and the other tube (outside tube) has the cold water running through it in the opposite direction.
So the hot wort is coming into continuous contact with very cold water.
To do this you will again need a recirculating pump to transfer the wort through the chiller and back into the kettle.
You connect the “wort in” end of the chiller to the kettle (by way of the pump) and put the “wort out” end of the tube back into the kettle.
You than connect your water source (hose) to the “water in” end of the chiller and on the “water out” end you connect a drain hose and drain it down a drain etc.
Some people do not like this method as they are concerned with cleaning the chiller afterwards. Since the wort runs through the chiller there could be a buildup of dried wort, etc inside the copper tubing.
I found that if I did a thorough rinse of the chiller by spraying a hose into both ends of the “wort in” and “wort out” sections no debris would build up. I would run the hose until the water ran clear.
I would also do a PBW or Oxi Clean soak of the inside of the unit from time to time. Just pump some into the unit and let it sit for 5 – 10 minutes and do a thorough rinse and you will be good to go.
When it comes to sanitizing the unit there really is no need to do so as the boiling wort will sanitize the inside of it for you.
So there you have it, my top 5 ways of how to cool wort. I trust you enjoyed this post and found some value from it.
If you need further help on anything home brew related I have put together a free guide that covers pretty much anything you need to know, you can check it out here!
If you have any questions at all drop them into the comment section below and I will be sure to help you out.
Cheers my friend, Big Robb is out!