The State Of Beer Boiling And Fermentation

How to identify the boiling state and effect of wort during the brewing process?

1. When the wort is boiled to the second half or before the end, take a sample of 250-300ml in a clean triangular flask, and place it in the mashing room at room temperature and cool to room temperature. Observe the wort in the triangular flask. There should be something at the bottom of the flask. Flocculent or muddy precipitation, the wort distributes a large amount of condensate evenly in the bottle, which can be flake, flocculent, etc. The wort is basically clear and transparent. The smell of the wort has a refreshing hop and malt aroma, no other abnormalities. Mixed smell, with obvious sweetness, bitterness and malt smell. Then place the triangular flask in a refrigerator at about 10°C overnight (or more than 12h) to observe the turbidity change of the wort.

2. Take it out the next day and observe that there should be thick deposits at the bottom of the triangular flask, which are like cauliflower clusters, and the supernatant is clear and transparent, indicating that the boiling effect is very good. If the supernatant is cloudy and turbid, it may be There are more cold coagulums or more polysaccharides. If the agglomerates are muddy and the number is not large, the protein aggregation will not be good.

How to identify the state of beer fermentation during the brewing process?

Observing the beer fermentation state, you can judge from the exhaust strength of the CO2 exhaust pipe that extends from the top of the tank to the fermentation operation room. The following identification methods are available:

1. After the fermentation tank is full, there will be a relatively strong CO2 gas flow out 6-8 hours, which proves that the yeast is in good condition and the fermentation liquid has begun to rise. At this time, gently fan the gas to exhaust the smell, and you can smell the wort. Clear fragrance and aroma of hops, as well as the smell of alcohol, aldehydes, and sulfides produced by anaerobic fermentation.

2. After more than ten or twenty hours after the fermentation tank is full, the fermentation liquid has completely entered the fermentation stage, and there should be a very strong CO2 gas flow, and the smell should have strong alcohol, aldehyde, ester, sulfide, etc. Stirring, at this time, the smell of wort should not be too obvious. If the CO2 gas flow is not large at this time, and there is a more obvious wort smell, it is in a state of slow onset and sugar reduction, lagging or slow fermentation, and pay close attention to the changes after 24h. 

3. Normally fermented fermentation broth has two obvious characteristics. One is that the discharged gas contains a large amount of low-carbon aldehydes, alcohols, and esters with relatively good volatility, so the odor is relatively irritating, and there are also comparisons. Obvious smell similar to sulfur compounds, even the smell of diacetyl, because these are the immature taste of the early fermentation stage of beer, if the fermentation is slow, the amount of such substances discharged is relatively small. The second is that the wort smell disappears relatively quickly. If there is still a strong wort smell 24 hours after the tank is full, it proves that the wine rises slowly and the fermentation is not vigorous enough.

4. After sealing the can and before cooling down, you can still feel a smell. For example, you can smell the refreshing aroma of beer (mixed smell of esters and alcohol flavors), and the irritating taste is not very strong. This is the normal performance of the fermented flavor. If there is still a strong irritating smell, even if you can smell such as sulfur dioxide or other bad immature smells, there may be some problems with the fermentation in this tank, and it proves that the content of aldehydes may be high, which requires attention to the fermentation broth during the warm storage stage Maintain a certain number of strong yeast cells to reduce aldehydes, or use CO₂ washing methods to reduce the influence of immature substances such as sulfur compounds and acetaldehyde on the flavor of beer.