Fermentation is a process that involves yeast converting glucose in the wort to ethyl alcohol and carbon dioxide gas so that your beer can have the alcohol content and carbonation. The fermentation process begins when cooled wort is transferred to a fermenting vessel before yeast is then added.
It would be best if you didn’t stir your homebrew during fermentation. If you stir it, you will end up re-oxygenating the wort, and this will also make your beer have off-flavors.But if you mistakenly shake your homebrew when it is closed, it will wake the yeast up a little. If you aerate your beer, it will become cloudy, and you will need to allow it to get settled.
For new brewers that want to know how long they need to give their beer to ferment correctly, it is pretty difficult determining that because you can’t control the process of fermentation immediately, you pitch your yeast. You will have to give your yeast time to perform its job.
The good news is that you can alter some conditions to reduce or prolong the fermentation time and control the fermentation temperature. But this will be based on the yeast strain you use and what you seek to achieve in the beer.
How can you control your fermentation temperature?
Controlling the fermentation temperature is very crucial because you can make some remarkable changes in fermentation as regards the timeframe and the quality of the finished product too.
You should be aware that each yeast strain comes with a specific temperature range they perform better in. If you use a different temperature for them, it can affect their fermentation ability. So, the cooler the temperature, the slower the yeast performs but, the warmer the weather, the faster the yeast works.
You will get a lot of unnecessary attributes in your beer and off-flavors if your fermentation is hotter outside of the stipulated yeast temperature range. And if the temperature outside the stipulated yeast temperature range is cooler, you will experience stalling and abnormal levels of fermentation.
What is the basic rule of thumb for fermentation temperatures?
Always go for a lower-middle temperature of the yeast fermentation range. But this rule may vary for some styles like Saisons and wheat beer because their fermentation procedures are very complex.
How will you know when your beer has finished fermenting?
Do not use the airlock activity in your beer to evaluate if your beer is done fermenting; instead, use a hydrometer or refractometer. These devices will help you to check the sugar levels in the beer or wort. Take a stable specific gravity (SG) reading of your beer over two to three days so it can help you know when your beer is completed and ready for packaging.
What should you do when your beer has finished fermenting?
Always give your beer enough time to rest when it is done fermenting so you can allow it to settle out and clear the yeast flocculating at the bottom of the fermenter.
Reducing the temperature can help in clearing the beer.
When you are sure that the fermentation is complete, you can then choose to package it immediately orage it longer and add other things like fruit or oak, depending on the beer you have brewed.
What will your beer look like when fermenting?
You should not end up spoiling the quality of your beer just because you want to see what it looks like while it is fermenting. Your beer looks like a Schrodinger’s cat while it is fermenting. But to see for yourself, you can use a clear or see-through ferment to watch the fermentation process within having to open the fermenter and exposing your beer to air.
So, what your beer looks like while fermentation is going on depends on the yeast you pitch in it. Once you pitch your yeast in your beer, it goes through a phase. Check out the different phases it goes through below.
- Lag phase
This phase lasts for about fifteen hours. This is where the yeast cells are waking up and are trying to find out what is happening. As soon as they wake up, they search for their morning stimulants like amino acids, minerals, and oxygen.
You won’t notice an airlock activity here, and you will only see a small amount of natural convection of the wort in the fermenter because of the remaining temperature stratification.
2. Growth phase
This phase lasts for four hours to four days. This is when the yeast begins to replicate and work on the sugars on the wort. Also, a foamy head of yeast proteins and sugars called the Krausen starts to grow.
Here, a large amount of carbon dioxide is produced, and the airlock activity becomes active. This is also when the heat convection in the wort begins to increase, and you will start to get a gentle rolling over of the wort in the fermenter.
This is the stage where plenty of the flavors, alcohol, and aroma compounds are produced.
3. Stationary phase
It takes three to ten days for this phase to finish. This phase is where all the easy sugars get eaten and the Krausen starts to change from creamy white to yellow and brown.
Here, the yeast starts to absorb a lot of the compounds that are called off-flavors like diacetyl, higher alcohols, sulfur compounds, and esters and transforms them into a lot of alcohol and even better esters.
This is the stage where there is no balance in the flavors, and the fermenting wort is known as green beer. This is where the airlock and the convection begin to slow down as the yeast settles into a long haul and goes to sleep.
4. Death Phase
This is the last phase in the fermentation process. It takes several weeks for this phase to end. In this phase, the airlock activity may stop, or you may notice just a few bubbles. Convection will also stop. The yeast is always asleep at this phase, and it hangs out at the bottom of your fermenter. This is the point when the beer starts to clarify and the flavors in the beer mature.
Is stirring your wine good?
The fermentation process of wine is quite different from that of beer. Immediately you pitch the yeast, and you will need to stir the fermenting wine around very for a long time. You will need to stir thoroughly so that none of the pulp becomes too dry during the fermentation process. You will also need to mix it around twice a day to get the maximum result. This whole process of stirring is known as punching the cap in a winery.
When grapes are being fermented, there is so much pulp you will have to deal with because usually, a thick solid cap is formed. So, as a winemaker, you will need to punch this thick solid cap down with a punch-down tool that looks like a large potato masher that has a long handle.
When you are making your grape wine, you will need to stir very well because the pulp is more than that of other kinds of wine.
You can use an average size of fermentation bag to stir your wine. All you need to do is open it up and mix the pulp very well to circulate the dryer pulp to the bottom. Keep rotating the pulp. You can get a fermentation bag from an online store.
Stirring your wine is an essential part of the winemaking process. You will need to stir your wine because if you don’t, the pulp will become too dry for a long time, and this will become a breeding ground for mold and bacteria to thrive. Stirring your wine is also vital because if you don’t mix it well, a solid dry layer gets formed, and it will alter the fermentation process.
The yeast that is pitched in your wine requires air to grow successfully and multiply into a big colony to support a healthy and active fermentation. If you don’t stir your wine well, a thick dried cap forms a hindrance that ends up trapping the carbon dioxide gas in the wine, and this will cut the air off from the yeast.
After the primary fermentation, when you are prepared to remove the fermentation bag, you will notice a decrease in volume, but it might not be as much as when you are using blackberries to make your wine.
After your primary fermentation, you might find out that your batch is too short; if that’s your situation, then you should consider topping up the wine when it is going into the secondary fermentation by adding more liquid. When you pull your fermentation bag out, try wringing it out very well so you will get plenty of wine.
Conclusion
You should avoid stirring your homebrew during fermentation, so you don’t tamper with the flavors and taste of your beer.
You should only stir your wine during fermentation because that’s the right thing for you to do. The fermentation process of wine is very different from that of beer.
If you have a good knowledge of the fermentation process of your homebrew, it will help you not make so many mistakes.