This week I’m going to touch on a technical topic that has been mentioned several times in previous articles on love2brew. Hot & cold break are two important phases of the brewing process that play an integral role on the end product. Managing these two breaks properly will result in an even better tasting and looking beer.

Let’s start by defining hot and cold break, followed by recognizing them and lastly managing each. Hot break is the coagulation of mostly proteins, but also a few other things, during the boil. These same proteins are responsible for chill haze in your end product. Chill haze is as it sounds, haze that forms when you chill your beer. When your boil starts and that head of foam forms, that has caused many a boil overs, you are witnessing the start of hot break. As the proteins clump together and become heavier they sink back into the boil which is why the foamy boil subsides after a while. If you use an anti-foam product it just accelerates this process by coagulating the proteins quickly. To reduce the likelihood of chill haze be sure to complete a strong rolling boil for at least 60 minutes to clump these proteins. Irish moss or the like will also help reduce chill haze. Some brewers like to scoop the foam that films up on the top of the boil after the break occurs. I personally do not worry too much about hot break, it gets collected during my chilling along with the cold break. Be careful, adding ingredients can also cause additional break and potential boil overs.

Cold break is the precipitation or flocculation of mostly proteins, but also tannins and hop matter, that form when chilling wort rapidly. When wort is chilled very rapidly cold break will begin to form at around 140F. When this is happening the wort will look a little like egg drop soup. An ice bath typically will not be sufficient to make an effective cold break, you will need an effective wort chiller in order to drop the temperature rapidly enough. An effective cold break improves clarity, stability, and flavor of beer. The addition of fining agents like Irish Moss or Whirlfloc will assist in the process. If you are using an ice bath, I highly recommend fining agents late in the boil to make up for the lack of a strong cold break. Not removing the cold break can, but not always, lead to off flavor including DMS, Sulfur, and Fusel Alcohols. This is why I prefer to chill and whirlpool in the kettle so I can leave the cold break behind in the kettle and not let it pass to the fermentor. This is especially important for those delicate lagers with intricate flavor profiles, ales are a little more forgiving. When I was using a plate chiller the cold break would go directly into the fermentor, most of the time if I was making an ale I would not remove the break. However, if I was making a lager, I would let the break settle in the fermentor and transfer the wort off the break into another fermentor before pitching the yeast. With all of that said, some break is healthy for the yeast, it contains nutrients essential to the growth and reproduction of the yeast. Don’t get too caught up in the break as long as you don’t have a ton in a delicate beer. If you do transfer off the break like I do you can always add in yeast nutrient and plenty of o2 which should make up for any deficiencies.

Both Hot and Cold break are the coagulation of materials, mainly proteins. Understanding how they form and controlling them can dramatically improve your brewing experience but reducing or eliminating boil overs. It can also improve the appearance and flavor of your brews by improving clarity and eliminating off flavors. Plan your break strategy based on the beer you're making, but in general don’t worry all that much about it (in my opinion). If your find you are having flavor or appearance issues then take a closer look at your process and tweak your break strategies to see if you get a better result. Take good notes, tweak your process, and do what works best for you and your system.