Beer fermentation: first and second, temperature and fermentation time

2024 Author: Isabella Gilson | [email protected]. Last modified: 2023-12-17 03:14

Fermentation or fermentation is the main process in the preparation of the most popular foamy drink (at home or at production facilities - it doesn't matter). During the fermentation of beer, the sugars that are in the mass are converted by microorganisms into alcohols, along with carbon dioxide and other elements present in the final product in small doses. Therefore, all homebrewers need to know how this procedure works. Our today's article will tell about it. We hope that the information is useful!

Beer yeast - who are they?

Beer fermentation is provided by brewer's yeast. Some of their varieties can function at low temperatures (0-15 degrees Celsius), being at the bottom of the tank. They are called grassroots or camp.

Another main variety, older and more popular infor centuries in Europe - ale or riding. These microorganisms "work" in heat (beer fermentation temperature is 15-27 degrees Celsius). And in the process they "hang out" in the upper layers of the wort. But at the end of the procedure, they also fall to the bottom of the tank, and the fermentation intensity drops significantly.

How yeast is handled

These are, first of all, living organisms, therefore, you need to handle them delicately, not subject them to: sudden changes in temperature, change in habitat, increase in pressure, ethyl content. Indeed, under negative conditions, they can slow down the fermentation of beer, even die. Yeast is usually “fermented” ahead of time, so that begin to perform its direct functions faster, and the risks of must contamination are reduced along the way.

Therefore, experts recommend that beginners in beer business half an hour before introducing microorganisms into the wort, take a disinfected container, pour half a glass of water (boiled, temperature within thirty degrees), add a little sugar and pour dry yeast. Then mix gently, but do not shake, and cover with a kitchen towel.

Introduction of microorganisms into wort

When the wort is fully prepared for the introduction of microorganisms there, you need to check the temperature again. It is best to introduce yeast in batches so that they feel perfect. Then, in a neat manner, not much, mix the whole mass in the container.

To ensure the start of beer fermentation, the temperature scale of the total mass when introducing microorganismsriding type should be 23-27 degrees (the dose of the product, as a rule, is indicated on the packaging from the manufacturer and varies around 10 grams per 20 liters of beer). And when using the grassroots, it is in the region of 17-23, gradually decreasing to 9-15 (dosage 20-50 grams per 20 liters).

Further procedures

1. Then we close the dishes tightly, install a water seal, pouring liquid into it up to half (boiled water with the addition of available disinfectants). We place the dishes on a raised platform to make it easier to pour the final product into bottles or kegs.
2. We monitor that during fermentation, the ambient temperature does not change much. You should not mix, shake, disturbing the wort.
3. The start of fermentation varies - from two hours to a day, it depends on the temperature regime of the must, on the general condition and he alth of microorganisms. Optimal - 20 degrees, since at lower temperatures the process proceeds rather slowly and reaches two to three weeks. And at 25, for example, the first fermentation of beer will be carried out too rapidly, for about three to five days (then the drink may have an undesirable aroma, and it will become cloudy, since the yeast is in a suspended position for a long time), and then beer for a long time will brighten.

End of fermentation

At the end of the process, there is no more foam on the surfaces, and the drink tastes unsweetened. In this case, microorganisms settle to the bottom of the container, and the beer is clarified. If the beer is cloudy poured overbottles, a yeast sediment is formed, which gives the drink an undesirable (so-called mash) taste, and if the bottle is opened, the microorganisms rush up, shaking the drink. But there is no need to delay the transfusion, since there will no longer be enough yeast in the “crystal” beer, and during carbonization (secondary fermentation), other forms of microorganisms begin to consume the added sugar.

Top-fermented beer

Modern mankind knows several ways to make a foamy drink. One of them is top fermentation. It is produced using the appropriate yeast (Saccharomyces cerevisiae). This process is more ancient in comparison with the grassroots counterpart. This is associated with a rather late invention of refrigerators. And until that moment, only a limited number of breweries had the conditions for “cold”, that is, bottom-fermentation of the drink. Therefore, according to the opinion of brewing historians, top fermentation at temperatures up to 24 degrees Celsius was predominant for a long time, for example, in the Middle Ages and much later. It is characteristic that top yeast does not divide for a long time after budding and form branched colonies. Bubbles of carbon dioxide form on them, pushing accumulations of microorganisms upward. Hence another name - ascending fermentation. When riding, higher alcohols and esters are formed in large quantities, and this cannot but affect the aroma and taste of the final product.

What varieties can be attributed to ridingfermentation? First of all, these are English ale, Belgian lambic, German altbier and wheat beer. Now the interest in the production of this kind of beer in the world has grown dramatically, which is associated with an increase in the number and capacity of craft mini-breweries.

Bottom Fermented Beer

Another production method uses the yeast saccharomyces pastorianus and is called bottom fermentation. It is the most modern, widespread everywhere in comparison with the top. And a drink prepared in this way can be stored for a long time without pasteurization (by the way, top-fermented beer is stored for only a few months). The risks of contamination of the wort are also reduced, since the process itself takes place at a much lower temperature (about 10 degrees).

Difference of bottom fermentation: in the process, the maximum concentration of microorganisms is at the bottom of the tank (top fermentation is characterized by the accumulation of yeast at the top of the wort). After the processing of carbohydrates, grassroots yeast also precipitates (some of them die, and some fall into hibernation). Grassroots beer is called lager.

On the second round

Secondary fermentation of beer is considered extremely necessary by specialists, since as a result of the main fermentation, along with ethyl, many by-products are produced that are quite harmful to humans. And they can affect the taste and smell of drinks. During secondary fermentation, some more sugar is added (carbonization), microorganisms are activated, and harmfulproducts are transformed, ceasing to have a direct impact on taste. This process consists in the maturation of the final product, the main conditions for it are the preservation of yeast activity.