One problem that homebrewers face is Beer Haze. Now, me being an avid beer drinker, I do understand that certain types of beer are supposed to have a certain level of cloudiness. Not only does haze affect the look of your brew, but it can provide you with a horrible tasting brew that you wouldn’t want to drink if your life depended on it. Beer haze occurs when the brewing and fermentation process has ended and it can be a sign of some unwanted issues. Hazes can indicate infection in your beer due to use of wild yeasts or bacteria resulting in improper hygiene causing the beer to spoil. In this case, the haze can’t be corrected and the beer can’t be salvaged. These are called biological hazes. Always practice good hygiene when it comes to your equipment and always use yeast that has good flocculation characteristics for better beer clarity.
Non-biological hazes are broken down into two categories: chill haze and permanent haze. Chill haze occurs when beer is cooled and the haze dissolves when the beer is warmed at 20 degrees Celsius or higher. Permanent haze is when the haze remains even if beer is at room temperature. Proteins and Polyphenols (tannins) are also contributing factors in non-biological hazes. Polyphenols are extracted from the beer ingredients during the brewing and fermentation process, so polyphenols are going to be in your beer naturally regardless of your brewing method or the type of beer you are brewing. That doesn’t mean that there’s nothing you can do to combat the problem.
If you have a beer that contains a lot of yeast, you can try a technique called cold conditioning for a few days to faze out the haze. If that doesn’t work, just simply filter out the yeast. Haze from too much yeast is a simple problem and very easy to fix. Always use the freshest ingredients possible. Using fresh malt and hops would be to your advantage in the fight against haze. Check water for carbonates. Water with carbonates exceeding 20 ppm will affect mash pH. Boil water for 15 to 30 minutes to reduce hardness. If the level of calcium in the water is insufficient, add calcium chloride to the water before boiling. Your mash pH should be no higher than 5.3. If you see your mash pH going above 5.3, you can add lactic acid to alter the pH. Protein rests and proper wort separation from hot and cold breaks before fermentation can minimize the risk of beer haze.
If your brew is an all-grain brew, your sparging method can contribute to beer haze. Your sparge water temperature should be no higher than 70 to 75 degrees Celsius. If the pH starts to rise above 5.3 during sparging, stop sparging. Add lactic acid to water to reduce pH of the runnings, then resume sparging. Using Irish Moss in your boil can help with beer haze as well. The recommended amount is 5g per 5 gallon batch. Make sure the moss is rehydrated before you add to boil. Make sure you have a good rolling boil and never boil for more than 2 hours. Allow beer to stand for 15 minutes after boil so hot break can settle with the hops. Chill your brew as quickly as possible after boil to allow proper cold break formation.