No Chill Brewing
As the name suggests, no-chill brewing is the simple process of skipping the chilling step of homebrewing.
It has had its ups and downs for me on California’s Central Coast. On the positive side a healthy new son joined our family, our first child. On the negative side rainfall has been scarce and we’re racking up yet another year of exceptional drought. The combination of the two means that I’ve been looking for ways to save both time and water on brew days.
Shortening your brew day is primarily an exercise in shortening or eliminating as many steps as possible from your critical path. One of the longest such tasks on brew day is chilling your wort from boiling down to yeast pitching temperature.
Depending on your chilling equipment, technique, batch size, and ground water temperature, chilling can take anywhere from 15–45 minutes. If you’re running tap water through the chiller this can then waste as much as five times as much water as a typical shower.
Industrious homebrewers may either capture this runoff in large storage containers or divert it to landscaping uses once it’s cool enough to avoid scalding plants. I’ve tried both methods and found they provide more hassle than I want to add to my brew day. Furthermore, neither method addressed the time savings I was looking to achieve.
It was then that I started considering a technique I’d heard about that ran counter to much of the common homebrewing wisdom but nonetheless met my needs: No-chill brewing. Like so many aspects of brewing history, be it homebrew or commercial, it’s difficult to determine the definitive origin of the practice. What is clear is that no-chill brewing came to prominence in the Australian homebrewing scene where water is scarce and conventions are often flouted. This may have been have been further encouraged by the practice of Australian brewers selling “cubes” of unfermented wort for customers to ferment at home.
No-Chill Brewing
Much like no-sparge brewing, no-chill brewing is defined by what is left out rather than what it includes. As the name suggests, the step of actively chilling the wort is skipped. At the end of the boil you simply turn off the flame, let the wort cool to just off boiling, drain it into a cleaned and sanitized heat-safe container, seal it up, and let it cool with the ambient air temperature over time.
Once the wort is at or near room temperature (usually about 8-12 hours later) transfer to your fermentor, aerate, and pitch as usual. If you are fermenting in a temperature- controlled space you can of course use that to get the wort right to your pitching temperature after the transfer.
That’s all there is to it. As I said, it’s more about what you don’t do than any special procedure. From my experience and research into others’ practices there are a few tips that can help:
• If possible squeeze all the excess air out of your containers. Air expands and contracts much more dramatically with temperature and so could result in some excess bulging or shrinking that deforms the container. Also, minimizing oxygen contact in this unpitched wort will decrease the potential for oxidation issues down the line.
• Make sure you place the filled container on a surface that can handle the high wort temperatures.
• Be extremely careful when transferring the hot wort as it can easily burn your skin.
• If using a hose to transfer the near boiling wort, make sure it’s made of a material that can handle the high temperatures. Regular PVC hose will leech chemicals and melt. Silicone is an excellent choice. The same is true of the wort container (read on). One note about silicone hose is that this material is normally not rated for much pressure when used with hot liquids. This is important for brewers who use pumps or gas pressure to help move hot wort. Teflon hose is another good choice.
Another variation of this approach is to simply leave the boiled wort in the brew kettle and seal it from outside contamination with something like a layer of aluminum foil while it cools.
Benefits
In addition to the obvious savings of reduced water usage, I realized several other benefits to my brewing when using the no-chill method.
First, I no longer needed to set up a pump and whirlpool immersion chiller in preparation for flame-out. That also meant I didn’t have to clean either of these items. I didn’t have to set up and eventually coil up my garden hoses either.
Second, I could remove a 20+ minute step from the critical path of my brew day. While the beer was chilling I was always twiddling my thumbs because all the vessels from earlier in the brew day were already cleaned and put away during the boil. Transferring sooner meant I could get to cleaning the brew kettle sooner.
Third, since the wort was all sealed up and sanitized I had a lot more flexibility on exactly when I’d pitch my yeast and so could more easily work around family obligations. I’ll get into timing a bit later in the article but there really shouldn’t be any concerns with waiting a day or two before pitching.
For a beginning brewer no-chill could simplify the brew day and significantly decrease the cost of moving to full wort boils. A properly sized copper immersion or counterflow chiller is one of the most expensive pieces of brew day equipment.
Thinking beyond the common brew day, no-chill would also work really well for large club brews or camping where water sources are a bit more limited.
Containers
Let me say right away that not all containers are suitable for receiving hot wort. On the top of that list are glass carboys as they aren’t made from a type of glass (such as borosilicate) that can handle large temperature changes. You will crack your glass carboy if you try to fill it with near-boiling wort.
Next on the list of problematic materials is PET, such as the material used in BetterBottles®. PET is only food safe up to about 120 °F (49 °C) and will shrink up and release chemicals at higher temperatures.
Beyond those two you should check with the manufacturer on any plastic container you want to use to ensure it’s food safe and resilient up to boiling temperatures.
Good choices for containers include anything stainless such as kegs or conicals, as well as plastic containers designed to receive high temperature foods. Two examples of the latter are the Winpack® tight head pails and HDPE carboys that are FDA approved. These can be found at the following links from US Plastics, a supplier to the food industry:
• 5-gallon (19-L) Blue Winpak® Tight Head Pail: http://www.usplastic.com/catalog/item.aspx?sku=75033
• 2.5-gallon (9.5-L) Square Poly Carboy: http://www.usplastic.com/catalog/item.aspx?sku=74093
I particularly like the 2.5-gallon (9.5-L) square poly carboys because they are easy to stack and maneuver around when full since they weigh much less than a full 5-gallon (19-L) batch. You may be able to source similar containers locally to avoid shipping costs. Just make sure that they are designed to safely store food at near-boiling temperatures.
Possible Issues
When people first hear of this technique they have several concerns because of the justification they’ve heard for quickly chilling and pitching beer. I’ll cover these in decreasing order of importance.
Botulism
Let’s hit this right up front. The process of no-chill brewing is similar to hot-packing for canning to preserve foods. To safely store foods that have a pH above 4.6, such as wort, the US Department of Agriculture recommends using a pressure cooker to process your containers at 240 °F to 250 °F (116 to 121 °C) for a number of minutes depending on the food type and container size. This is required to ensure that all spores of Clostridium botulinum are killed.
Literature on the actual risk of botulism poisoning from stored wort is sparse, and while the risk is low, botulism can be fatal so it is important to explore the risk. The history of botulism falls into two primary groups. The first is with foods that contain bot spores that are then processed in a way that leads to vegetative cell growth, followed by sporulation. This is when bot toxin is released. Canned vegetables and pickled olives are two examples of this. The second major grouping is when foods that do not have bot spores are processed and then contaminated post processing. There was a famous incident with canned salmon where the source of the bot spores was the cooling water used to cool the cans after processing. Leaky can seams caused water to be sucked into the cans after processing and the anaerobic environment lead to cell growth.
The key thing to know about C. botulinum is that is an anaerobic organism and that bot toxin is not produced when the cells are in an aerobic environment. Boiled wort is not an anaerobic environment, even before wort aeration. Chris Colby has an excellent discussion of this topic in depth on his blog at http://beerandwinejournal.com/botulism/.
Recommendation: Pitch your yeast promptly rather than store the wort for extended periods of time.
Contamination
One reason to pitch your yeast quickly is so that undesirable contaminating yeast and bacteria don’t have a chance to get a foothold in your wort and affect the flavor. It is not feasible to produce completely sterile wort and transfer it to a sterile fermenter without picking up at least some minuscule amount of yeast and bacteria.
Recommendation: Ensure your cooling containers are clean and sanitized. That in combination with pasteurization from the extended contact with hot wort means the risk is actually quite low.
Bitterness
An area of significant recent discussion in the homebrewing world is the effects of late hop additions on the bitterness of a beer. For example, a flame out addition to wort that is then chilled very quickly contributes little bitterness. On the other hand hops added to a wort that is going to spend 30 minutes in a hot whirlpool can contribute significant bitterness. At play here is the fact that alpha acid from hops continues to isomerize even when the wort isn’t boiling.
I have not been able to track down any reliable calculations for the impact of late additions with respect to no-chill brewing. As it’s unlikely commercial brewers will adopt this practice any time soon, the homebrewing community is going to have to come up with ways of quantifying this as this becomes more popular. Until that time it will largely be trial and error.
Recommendation: Consider dialing back quantities of late hop additions if they normally would have had little time to isomerize and contribute to bitterness. Alternatively, consider lower alpha hops for late additions to minimize the impact.
Dimethyl Sulfide (DMS)
The presence of DMS can cause an off flavor or aroma reminiscent of cooked corn or vegetables in a beer. One common source is the conversion of the precursor substance S-Methyl Methio-nine (SMM) at high temperatures. DMS is driven out of the wort by a vigorous boil but once the boil stops there is a period of time when SMM can continue to convert to DMS in the hot wort and carry over to the finished beer.
While this is an often-theorized shortcoming of no-chill brewing, in my experience and research I haven’t found it to be a common problem. This is likely because at a homebrew scale the conversion of SMM to DMS and the off gassing during a vigorous boil means that there is little precursor left to cause problems during the extended cooling.
Recommendation: Use 60-minute boils for most grain bills and 90-minute boils for very lightly kilned base malts that have high levels of the SMM precursor.
Clarity
A commonly stated reason for quickly chilling wort is to get a strong “cold break” where proteins flocculate and precipitate out of the wort. What is unclear is whether a similar process is at work with a slower chill over a longer period of time. Those who hear about this technique often cite this reasoning as a concern, but I’ve been unable to track down cases where this panned out to be a real issue. That’s quite possibly because with no-chill brewing the wort has a longer time to settle before transfer and so even though the cold break flocs are smaller they still fall to the bottom and are left behind.
Recommendation: This doesn’t appear to be an actual issue in practice.
Try No-Chill
While I know that some homebrewers have the luxury of freely available water and time, there are many like me that need options to manage these scarce resources. No-chill brewing seems to offer one solution with minimal downsides in terms of beer quality at the homebrew scale. I look forward to lower water bills and more flexibility in squeezing in brew sessions so I can pursue the hobby I love without having to give up valuable family time.
I encourage all of you to try this at home too. It’s a perfect opportunity to split a batch and compare the results as you can simply run off half your wort into a no-chill container and then chill the rest as you usually would. Ferment side by side and then share the results with your homebrew club to get as much feedback as possible. We’d love to hear your experiences with this convention-busting technique!
