Brew Tips #4: Fermentation
Despite my own understanding of fermentation I allowed myself to be taken in by some of the things read online. Though, I think in part that was on purpose. Blindly following instructions early on is how new brewers get started, right? But, as I sat back and thought about it, I feel like in retrospect it may have been a bad idea (though no harm done, because I didn't listen anyway, and listening wouldn't have hurt my beer any regardless).
There are (broadly speaking) 3 stages of fermentation when making beer. Primary, secondary and aging. There are also others like the lag phase, but for simplicity I don't want to go that deep. Some skip secondary, some swear by it. Some make the lengths of each stage the same every time. Some recommend 7 days in primary, others 10. Some recommend 1 week in secondary, some 2. So, who is right?
Well, everyone and no one. What plan you follow with regards to fermentation may have a huge effect, or very little (assuming you don't go wild and deviate crazily).
Firstly, I plan on having a planned process because I'm lazy, and in all seriousness attempting to calculate the effect of aging would be astronomically harder than people who believe they know the impact could ever fathom. Basically, you'd need to brew a bunch of IDENTICAL batches, treated identically in every way except fermentation stages (including controlling temperature, yeast cultures and numerous other things that would be damn near impossible across separate batches and even hard if a single batch were split). Suffice it to say, if someone told you there was a huge difference between aging 7 and 10 days, the difference was MUCH more likely to be introduced elsewhere.
My approach, going forward, (if dry-hopping) will be 7 days in primary, 7 days in secondary and then an appropriate amount of aging time in bottles based on the beer. If not dry-hopping, 10 days in primary, then to the bottles. If there is still a solid ferment going on after 7 days I'll ride it out however.
Why those lengths? Primary fermentation, in most cases will be largely wrapped up in 7-10 days and in many cases (excluding high gravity beers), even quicker. During this phase, most of what the yeast is doing is converting the simple sugars to alcohol. There is generally a lot of undesirable stuff generated during this phase, but the yeast are largely ignoring and it will stay that way as long as you don't leave on top of it too long. But, competing with that, if you aren't racking for a secondary fermentation, you also want as much sediment fallen out as possible before bottling. Hence the longer primary time when skipping secondary.
And that leads us to secondary fermentation. The yeast which are still active will still convert simple sugars if they find them as they did during primary, but most of what is still active is now working on consuming some byproducts from primary fermentation and more complex sugars. Generally, you can think of secondary fermentation as less of a fermentation phase and more of a control phase. Add flavor and aromas with hops and wait for stuff to drop out of suspension. It is really just a nice side-effect that it your beer is aging at the same time.
So, why ever skip secondary? Well, this is because I'm bottling rather than forced carbonating a keg. Let your beer sit too long and enough of the healthy yeast cells will have fallen out that you won't have enough to carbonate your bottles. You could always pitch another pack of the same yeast and stir it in before bottling. Simply put, easier and fewer places for human error while not taking a gamble.
OK, if secondary has those risks, why do it all? For better control, and because for some the yeast is no longer a concern at this stage. If you had planned to pitch another pack anyway or you're force carbonating, this is a great chance to tweak things and let it clear up more before bottling. Enough people do secondary to suggest that the gamble on aerating the beer can't be too bad.
Which finally leaves us at bottling. For those who do it, bottling can technically happen any time after fermentation has slowed sufficiently. You add sugar and potentially more yeast, rack into bottles and then wait for it to carbonate (1-2 weeks in many cases) and then age as long as you like. If you didn't do secondary you'll probably be wise to leave it in bottles longer before drinking.
I guess that is another nice thing about secondary fermentation. It gives you something to do to quench the impatience.
Hopefully that's all helpful and provided some insights into why people do this differently, but also why you may be able to streamline or improve on your own process depending on your preferences.
There are (broadly speaking) 3 stages of fermentation when making beer. Primary, secondary and aging. There are also others like the lag phase, but for simplicity I don't want to go that deep. Some skip secondary, some swear by it. Some make the lengths of each stage the same every time. Some recommend 7 days in primary, others 10. Some recommend 1 week in secondary, some 2. So, who is right?
Well, everyone and no one. What plan you follow with regards to fermentation may have a huge effect, or very little (assuming you don't go wild and deviate crazily).
Firstly, I plan on having a planned process because I'm lazy, and in all seriousness attempting to calculate the effect of aging would be astronomically harder than people who believe they know the impact could ever fathom. Basically, you'd need to brew a bunch of IDENTICAL batches, treated identically in every way except fermentation stages (including controlling temperature, yeast cultures and numerous other things that would be damn near impossible across separate batches and even hard if a single batch were split). Suffice it to say, if someone told you there was a huge difference between aging 7 and 10 days, the difference was MUCH more likely to be introduced elsewhere.
My approach, going forward, (if dry-hopping) will be 7 days in primary, 7 days in secondary and then an appropriate amount of aging time in bottles based on the beer. If not dry-hopping, 10 days in primary, then to the bottles. If there is still a solid ferment going on after 7 days I'll ride it out however.
Why those lengths? Primary fermentation, in most cases will be largely wrapped up in 7-10 days and in many cases (excluding high gravity beers), even quicker. During this phase, most of what the yeast is doing is converting the simple sugars to alcohol. There is generally a lot of undesirable stuff generated during this phase, but the yeast are largely ignoring and it will stay that way as long as you don't leave on top of it too long. But, competing with that, if you aren't racking for a secondary fermentation, you also want as much sediment fallen out as possible before bottling. Hence the longer primary time when skipping secondary.
And that leads us to secondary fermentation. The yeast which are still active will still convert simple sugars if they find them as they did during primary, but most of what is still active is now working on consuming some byproducts from primary fermentation and more complex sugars. Generally, you can think of secondary fermentation as less of a fermentation phase and more of a control phase. Add flavor and aromas with hops and wait for stuff to drop out of suspension. It is really just a nice side-effect that it your beer is aging at the same time.
So, why ever skip secondary? Well, this is because I'm bottling rather than forced carbonating a keg. Let your beer sit too long and enough of the healthy yeast cells will have fallen out that you won't have enough to carbonate your bottles. You could always pitch another pack of the same yeast and stir it in before bottling. Simply put, easier and fewer places for human error while not taking a gamble.
OK, if secondary has those risks, why do it all? For better control, and because for some the yeast is no longer a concern at this stage. If you had planned to pitch another pack anyway or you're force carbonating, this is a great chance to tweak things and let it clear up more before bottling. Enough people do secondary to suggest that the gamble on aerating the beer can't be too bad.
Which finally leaves us at bottling. For those who do it, bottling can technically happen any time after fermentation has slowed sufficiently. You add sugar and potentially more yeast, rack into bottles and then wait for it to carbonate (1-2 weeks in many cases) and then age as long as you like. If you didn't do secondary you'll probably be wise to leave it in bottles longer before drinking.
I guess that is another nice thing about secondary fermentation. It gives you something to do to quench the impatience.
Hopefully that's all helpful and provided some insights into why people do this differently, but also why you may be able to streamline or improve on your own process depending on your preferences.
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