In the past, connoisseurs felt that cloudy beer was bad. You heard your draft beer get clear, sparkling and clean in your glass. But some styles are more likely to be cloudy, such as wheat beer, Weiss and Blanche, because of protein in your beer. That is part of the beer and is a natural reaction to polyphenols in the beer.
- What are polyphenols?
- Organic brewing problems
- Chemical brewing problems
- Cold cloudiness
- What can you do about chemical conditions in beer
- Too much starch in my beer?
- How do you test the beer for starch with iodine
What are polyphenols?
A polyhenol is an organic molecule that is present in most plants. When polyphenols combine with proteins, you get cloudy beer. And cloudy beers, unfortunately, have a shorter shelf life than other styles and are more easily affected by oxidation. There are, however, ways in which you can make your beer clearer.
There are two types of problems that can affect your beer: one is biological and the other chemical.
Organic brewing problems
In the worst case, wild yeasts and bacteria can contaminate your beer. This is often due to poor hygiene and can lead to unpleasant sour and moldy tastes during tasting. It can also be the result of an excess of yeast in your brew.
To combat this biological problem it is necessary to use yeast with ‘flocculant’ or ‘flocculation’ properties. Flocculation is the ability of yeast to end up at the bottom of your fermentation vessel at the end of fermentation. Some yeasts have the ability to bind together to form aggregates and to pull all the flakes to the bottom. That way, when bottling, you can leave that low yeast in the barrel and the clear beer goes into your bottles. You can strengthen the yeast layer on the bottom by giving your beer a cold shock – cooling it off as quickly as possible at the end of the fermentation period for 12 to 24 hours.
If the cooling of your beer does not sufficiently reduce the turbidity, you can filter your beer by centrifugation or filtration, but that requires special equipment.
Chemical brewing problems
These are caused by a combination of proteins and polyphenols. These polyphenols, also called tannins, often lead to acidity and bitterness in beer. Brewers pay a lot of attention to these kinds of problems because polyphenols are the first elements that undergo oxidation in beer.
This oxidation ensures that the polyphenols bind to proteins and the precipitation of proteins in the wort, which shortens the shelf life of the beer.
Cold cloudiness or cold breakage is the main cause of cloudiness in home-brewed beer. It arises when the beer is cooled to 0 ° C and dissolves when the beer heats up to 20 ° C. It is caused by too slow a cooling of the wort after cooking. By investing in a wort cooler you can cool the beer faster and avoid this problem.
What can you do about chemical conditions in beer
– Ensure good quality ingredients. For example, store hops in a dark, cool place
– Limit the use of protein-rich grains (wheat, oats) and prefer barley.
– Correct the pH of your maize (water + malts) by adding acid (for example lactic acid), aim for a pH of 5.3 for the first phase of beta-amylase saccharification (62-63 ° C).
– Cool your wort as quickly as possible using a plate cooler or ice water
– At the end of cooking, turn off the gas while the wort is boiling and then add a clarifying agent. The best known is carrageenan moss, an Irish moss that solidifies the proteins on the bottom of your fermentor. You can also use regular kitchen gelatin. Some professional breweries use isinglass, dried fish casings in pedervomd (Mmmmm!)
– An efficient filtration system for insoluble pieces will also help, but requires more investment in equipment.
– Avoid oxidation by limiting the contact between your beer and the outside air and make sure it does not splash during the transfer.
Too much starch in my beer?
With all-grain brewing it is possible that the turnover of starch was not complete and therefore required a longer period of mashing. If your all-grain beer is still toeble at the end of the first phase, then it is certainly possible that there are still traces of starch in the wort. To solve this problem, you have to go through the mashing steps again and brew longer. It is annoying, but it can lead to better beer.
How do you test the beer for starch with iodine
This test makes it possible to check the presence of starch, and therefore the complete sugarification, on the basis of the reaction between iodine and starch. Take a sample from your wort and add a few drops of iodine. The iodine will turn blue if there is starch that has not been converted into simple sugars. Warning: Iodine is a poison, so you MUST discard the sample after testing.