Secondary fermentation- a technological process in brewing, which has long been the subject of controversy and there is still no consensus on its feasibility. Some people consider it mandatory, while others decide to skip it. Let's try to understand this issue, weighing all the pros and cons.
Secondary fermentation means transferring the wort after active fermentation has completed into a similar fermenter, in which the beer is separated from the sediment and left for further fermentation.
The benefits of secondary fermentation are obvious and come from the separation of beer from dead yeast cells, suspended hops and grain remaining after boiling, as well as tannins that settle as sediment to the bottom of the fermenter during primary fermentation. All of this can introduce undesirable flavors and make the final product cloudy. Some of the problems are eliminated by using ready-made malt extracts, which make it possible to obtain a fairly clean and transparent wort, but yeast sediment will form in any case. This yeast, lying in large quantities at the bottom, can begin to die and decompose. This process, called autolysis, generates its own inappropriate good beer bouquets of aromas and tastes.
Until recently, secondary fermentation was considered mandatory by most brewers. The same principle is used in most large and not very large breweries, but it is carried out there not by pouring fermenting beer into another container, but by draining the sediment itself through a special tap located at the bottom of the cone-shaped CCT. This is certainly a convenient and reasonable solution to the problem, but home brewers usually use much more primitive equipment and the question of secondary fermentation remains open for them.
It is also worth considering that despite all the attractiveness of this technology, it also has certain disadvantages, due to which this stage in home brewing is often skipped. The most significant of them are the danger of beer contamination during transfer, as well as the likelihood of wort oxidation due to its interaction with oxygen.
Not even very a large number of oxygen can cause significant harm to the finished beer, therefore, when pouring, you should use equipment that minimizes the contact of the wort with air, such as special siphons for bottling, and other devices that perform similar functions. And to avoid infection, it is worth paying special attention to the disinfection of the secondary container and all equipment involved in the overflow.
As a result we have obvious benefit from pouring beer into secondary fermentation on the one hand and quite high risks associated with it on the other. When solving this dilemma, it is also worth considering the following factors: how long it will take for fermentation in general, the density of the beer and the volume of yeast pitch, the amount of hops used and its volume in the fermenter, and whether you have the necessary equipment for safe transfer.
I don’t think the issue with the equipment should raise any questions, so let’s pay attention to other factors:
1. Fermentation time. If the total fermentation time and, as a consequence, the time the beer remains in the fermenter for some reason will be longer than two weeks, then it will be very useful to remove the beer from the sediment after the completion of active fermentation.
2. Density of beer and volume of yeast pitching. When preparing dense, strong varieties, which usually require more yeast, the volume of yeast sediment will inevitably increase. Considering that in such cases the time required for fermentation of the wort also increases, then in this situation, transferring to the “secondary” will not be deprived.
3. The amount of hops used and its volume in the fermenter. After hopping the wort, a significant amount of hops can also enter the fermenter, which will precipitate during active fermentation. If your equipment does not allow it to be cut off when transferring the wort to the fermenter, then it would be wise to transfer the beer to secondary fermentation.
4. This also makes sense when making beer using dry hopping. In this case, hops should be added to the secondary fermenter in the beer removed from the sediment, which will allow, by avoiding the problems described above, to also get a greater effect from such hopping.
In any case, the decision to transfer to secondary fermentation remains on the conscience of the brewer and there cannot be a single answer without taking into account all the circumstances. If you have questions on this topic, you can discuss specific situations and get recommendations from experienced brewers on our forum.
Hello, Dear Alexander, the old moonshiner and aspiring brewer Yuri is writing to you again :) I am somewhat perplexed by the current practice of homebrewers (and I carefully study their correspondence on the forums that I was able to find) on fermentation technology, more precisely, the division into phases: main fermentation, secondary fermentation, carbonation. In the book Technology of Malt and Beer, published by a team of Czech authors in 1958, two phases are considered everywhere: main fermentation and post-fermentation with one transfer to post-fermentation (which, however, is divided into post-fermentation and maturation itself. I’ve been reading this book for about 15 years, I wonder why Kuntze didn’t come up with another name for his work :). So, that’s what I do, after the main fermentation, about three days, I pour the beer into an airtight container and after a couple of weeks I enjoy my creation, I try to do it without adding glucose, using residual sugar , that’s what the Czechs taught me :) I don’t understand why pour it into some kind of secondary fermentation, wait for something, and then add sugar and yeast again? By the way, in this article you write that Kunze is talking about the same thing. The technology of closed fermentation with water seals is amazing!!! Remember, Kunze and my favorite Czechs write that it is necessary to skim off the yeast foam every 3 - 6 hours; in the old days, beer simply fermented in a barrel without a cork and the foam simply came out on its own, and the brewer only topped up the barrel with wort or water, they do the same now and “stupid” Americans (they ferment the wort in conical water bottles filled to the top with wort and a wide hose through which the foam is removed) everything ingenious is simple. I would very much like to know your opinion on these issues. And I’ll really be bold and allow myself to disagree with your ironic attitude towards refrigerated plates, expressed a couple of years ago on the Teddy Beer forum, the Czechs claim that the oxidation of the wort, so necessary for proper foaming and improving the taste, is possible only at high temperatures of the wort, which is occurs on plates, and effective aeration is possible with low temperatures, after cooling, these are two different processes, I was amazed how a very experienced home brewer, not that I am a novice dropout, calls a photo of an ordinary refrigerated plate in the attic of a brewery a container for fermenting Belgian lambricks, based on the fact that large gaps are left in the roof and neither who didn't correct him. (May this person forgive me if he suddenly reads my writings:)) And lastly, I would very much like to know your opinion about the shelf life of homemade “horse” beer. both the Czechs and Kunze write about its low biological stability and the need for rapid use. And here are all the docks home brewing They unanimously talk about its long shelf life, but I haven’t read that from you, though. Perhaps it is dense, with a high degree of fermentation and will last a long time, but that’s what our people love :) ordinary beer, like the Czech Prazdroj, with a strength of 3 degrees and an initial density of 13%, how is it? Thanks in advance. if you could share your thoughts, novice brewer and experienced moonshiner, Yuri
Includes stages, each of which must be completed according to the rules. Otherwise, the beer will not have the desired taste. There are no trifles here: the type of yeast used, the fermentation vessel for the beer, and the aging time of the drink are all important. Let's look at the main points.
First: choose the yeast. Types of yeast used in brewing:
- dry (in powder form);
- pills;
- liquid.
Preferably added to drink dry yeast. The reason: they are easy to transport, and in addition, they are stored in almost any conditions. Disadvantage of this type: less interesting taste qualities than liquid yeast.
The choice of yeast also depends on what kind of beer you want to make: ale or lager. So, for lager varieties we take Fementis-Saflager 34/70.
To brew ale (read:), it would be nice to get SafaleS-04. This subspecies is perfect for fermentation in wooden barrels.
What is yeast? This is the product received from malt and hops by fermentation. Without them, making beer is impossible. Before you “fill” the wort with them, you need to prepare them correctly.
Preparation
No special preparation is required for liquid yeast, but dry yeast requires a little work. The steps are as follows:
- We disinfect capacity selected for the process.
- Pour it in warm water (the temperature of which is from 26 to 28ºС).
- Scatter dry yeast on top.
- Covering the dishes foil.
- We leave for 40 minutes.
- Shake the liquid until a suspension is obtained.
- Add the resulting suspension to the wort.
On this preparatory stage completed: now we are waiting for fermentation and the moment when tasting the drink begins.
Choosing a container for beer fermentation
Beginning brewers are thinking about the question: which fermentation vessel is suitable for preparing the drink? Most often the choice is stopped on a plastic container.
The brewer's task is not to make a mistake with the size of the container. It must be spacious, because foam will form, which will overflow the edges if the volume of the container is insufficient.
You place the container and pour the wort into it. Do not forget open the lid slightly. This is necessary so that too vigorous fermentation stops. A week passes. After this, the future beer is removed from the sediment and left for secondary fermentation.
Top fermentation
Initially, there was only a method of top fermentation. Why? It was not always possible to reach temperatures below 14ºС. Temperature required for riding from 15 to 25ºС. Yeast does not separate for a long time during the top fermentation process. They form colonies of gas bubbles.
Top fermentation is gradual formation of higher alcohols and ethers. This is how ale or German wheat beer is produced. These taste alcoholic drinks somewhat coarser than those obtained by bottom fermentation.
Bottom fermentation
At bottom fermentation yeast settle at the bottom of the container, in which the whole process takes place. This beer is brewed in cold rooms, carefully ensuring that temperature regime was not violated. The yeast should settle to the bottom of the container.
Lager varieties formed in this way are more pleasant to the taste, according to many connoisseurs. Another plus: lager varieties They last longer and are easier to transport.
Fermentation stages
The whole process is divided at stage 4, during which future beer gradually becomes what we are used to.
- The wort was poured into a vat and the yeast was placed there. Carbon dioxide is being released. gas bubbles rise to the surface. We wait from 12 to 20 hours: during this time, white foam appears. At this time, we can consider that the first stage has come to an end.
- At the second stage, take a closer look at the wort: do you see curls on the surface? They resemble roses appearance. This means that the yeast has begun to multiply quickly, which means that fermentation is intensifying. Everything goes according to plan.
- The third stage is characterized by a change in the color of the curls. They turn brown and rise higher.
Attention! At this stage, watch carefully by wort temperature! It grows, so it is necessary to cool the future beer from time to time, bringing it to a temperature of 6 or 7ºC.
- Last stage: stopping fermentation. The curls fall off. The yeast “sinks” to the bottom, the beer becomes lighter.
Do you think that the cooking process foamy drink completed? No, there is one more stage ahead, but it will take place in a different container.
End of fermentation stages
To know that fermentation is complete, inspect the liquid. Assess its uniformity. Check did the yeast sink to the bottom?. Pay attention to the color: if it is cloudy, it means you need to wait a little longer. If the beer becomes light, it can be poured into a glass container.
Transferring the wort
Check that the wort temperature is from 8 to 10ºС. If this is the case, prepare clean glass containers. Further fermentation will take place in them.
These can be cute bottles in which you will then serve beer to the table. Pour carefully so that no sediment gets into the bottles. Use a siphon tube for this.
Post-fermentation
Here we come to the end technological process. But you don’t just need to pour the beer into bottles and put it away for a while out of the reach of children and guests. Into bottles add something containing sugar:
- sugar;
- glucose;
- sugar syrup.
The calculation here is this: you need 9 g of sugar-containing product per 1 liter of wort. During the fermentation process, carbon dioxide is formed. Beer should be stored in glass containers at a temperature of 18-20ºС. Fermentation is necessary for the drink to acquire pleasant taste and aroma.
Shelf life
Beer industrial production, if it is “alive”, stored for 3 days. If you followed the production technology, then homemade drink can stand for three days- nothing will happen to him.
If beer is prepared using the high-pressure method, the shelf life increases up to 3 months. To extend the shelf life, try to comply with the following conditions:
- place bottles vertically;
- seal containers tightly;
- do not expose beer to sunlight;
- Protect the drink from both overheating and hypothermia.
If you spend pasteurization of alcohol, then the shelf life will increase to 6 months.
Have you ever made beer at home? Tell us about your experience. Also share your opinion: what home product differs from the industrially produced analogue. What tastes better?
Try making beer with own kitchen. Its indisputable advantage: they are used only natural ingredients . In addition, you personally selected the products and brewed the drink step by step, preventing the interference of “foreign elements”.
Useful videos
Look at the order of fermentation homemade beer— all stages:
Personal experience of removing the sediment and transferring it to secondary fermentation, see:
About the primary and secondary fermentation of beer in a regular container, look:
If you are an experienced brewer, you will probably find something to advise beginners. How to carry out fermentation so that the taste is beyond praise? Share information with us, and we will post it on our pages. See you again!
Secondary fermentation of beer at home, as a stage of beer maturation, is very important. This stage has at least three goals:
- Increasing beer strength
- Final maturation of beer
- Carbonation of beer.
Increasing beer strength
When brewing strong beer it should reach high level. In the process of eating sugars, alcohol and carbon dioxide are produced, respectively, the more, the higher, from which the strength of the finished drink also increases.
Alcohol and carbon dioxide are waste products that interfere with their vital functions. Not every strain is able to withstand increased load; in some cases, a large amount of sugar remains because it ended early.
In this case, it is useful to remove the frozen ones from the tank and introduce new ones for secondary fermentation. When you re-ferment beer at home, the fresh cells are able to process the remaining sugars, increasing the alcohol content.
Final maturation of beer
Often at home it is difficult to maintain a certain temperature, as a result of which the ripening process cannot be controlled, the most correct solution is in this case the secondary fermentation of beer will start. You can do this in two ways:
- or add sugar for additional nutrition;
- or add new ones if there is a lot of sugar left after the main one, but it has stopped.
The fact is that in the process of the main thing, along with ethyl alcohol produce many other by-products. Subsequently, under the influence of yeast enzymes, these products are broken down and transformed to a state that does not affect the taste of beer. This is precisely the essence of ripening, the main condition of which is the preservation of yeast activity.
Carbonation of beer
One of the main problems at home is the lack of necessary containers where beer can be stored under high pressure. Most often, further maturation processes take place in open containers, after which the beer is poured into consumer containers. However, in this case, beer is not able to accumulate carbon dioxide.
Secondary fermentation of beer at home solves this problem too. After pouring the beer into consumer containers, add a small amount of sugar for renewal. The released gas in the bottle creates enough pressure to carbonate the beer. At this stage it is important not to overdo it with sugar, otherwise the beer will become sweet. After cooling the bottle, the gas will dissolve in the beer and precipitate. Thus, at the end we will get an almost transparent bottle of cold beer with yeast sediment at the bottom.
Most home brewers use a technique called “secondary fermentation.” You will not find this term in scientific works on brewing, and any qualified brewer-technologist is unlikely to have ever heard of such a phrase. Everything is logical: the vast majority of modern commercial breweries use CCT - cylindrical-conical tanks, which allow you to get rid of the yeast accumulated at the bottom by simply opening the valve. Similar equipment also exists in miniature form for home brewing, but not many people can boast of owning it.
Most brewers use regular flat-bottomed plastic containers for fermentation, so it's a good idea to skim the beer off the yeast sediment by pouring it into another container and leaving it there for a few more days to clarify.
IMPORTANT! After fermentation, the wort becomes beer, from which point its contact with air should be limited as much as possible. Beer should only be poured “under the layer” using a flexible plastic tube (that is, beer should not be poured over the top of the container in the usual way, it is necessary that the end of the tube is immersed in beer).
Dry hopping
A very common way to enhance hop aroma in beer is the so-called “dry hopping” (from the English dry hopping, sometimes the term “cold hopping” is used). Its essence is as follows: hops are not added to the wort during boiling, but directly to young beer after the completion of the main fermentation, that is, the beer is literally infused with hops. At the same time, bitter substances practically do not transfer into beer due to the low hopping temperature, but all the aromatics are revealed in a very strong way. Some modern beer styles cannot be imagined without dry hopping, so this method of adding hops is very common among amateur brewers. Historically, dry hopping was common in, for example, the UK. There are even stories of shipwrecks where surviving sailors floated among the wreckage of the ship and hops from broken kegs of beer. In modern brewing culture, dry hopping is more associated with bright American pale ales. However, it is used in many beer cultures - from German to Belgian.
Bottling beer
In breweries, beer is bottled for the sole purpose of delivering it to the consumer. But at home, bottling beer is an important part of the technological process! The fact is that during the ripening of beer in a fermenter, almost all the carbon dioxide formed during the fermentation process comes out of the drink, which means that we somehow need to return the sparklingness to the beer. To do this, beer is bottled, and, as noted above, a small amount of fermentable sugars is added - most often glucose. The remaining yeast in the beer will process these sugars within a few days and thereby carbonate (carbonate) the beer.
Even after being carbonated, beer continues to mature, which is why it can be stored for years. While filtered beer ages, homemade beer matures. Beer can be poured into both plastic and glass containers, but it should be remembered that beer is stored much worse in plastic, since PET allows air oxygen inside. Of course, homemade beer can also be poured into kegs; in this case, there is no need to calculate the amount of sugars for carbonation - it can be done artificially by connecting a cylinder with carbon dioxide. But, obviously, not all brewers are ready to purchase and maintain keg equipment, as well as regularly refill gas cylinders.
Always bottle your beer responsibly! Excessive carbonation caused by big amount fermentable sugars in the bottle or even simply bottling unfermented beer will lead to excess pressure in the container. And if in the case of plastic bottles if the case is limited to beer splashing when opening, glass bottles may eventually begin to explode and injure people.
