Very rapid fermentation - Is this bad?

[dogbert]

Good day,

I primarily take part in mead making, and have been doing it for over a decade now. Once in a while, I do a batch of all grain pale ale or bitters.

I just did a simple recipe recently for a slightly bitter ale.

• 10lbs pale two-row malted grains
• 1.5lbs crystal 60 deg malted grains
• 1.0oz centennial hops (45 mins of boiling)
• 1.0oz cascade hops (15 mins of boiling)
• 0.5oz cascade hops (5 mins of boiling)
• Irish moss (1tablespoon, last 5 minutes)
• Lemon zest (2 tables spoons, no pith, last 5 minutes of boiling)

I decided to apply the staggered nutrient addition method I use with mead making, which involves adding di-ammonium phosphate (DAP) and yeast energizer (ie: super food, B-vitamins, etc) in certain proportions at the time of pitching the yeast, as well as at the 1/3rd and 2/3rd sugar break points. With mead, this let's me complete the entire fermentation in about 12-14 days, and the mead is completely dried out. I can then rack it, let it bulk age for a couple months, then bottle and back sweeten it if I want to.

Well, this batch of beer appears to have reached it's FG in only 3 days. The fermentation took about 8 hours to really kick off after pitching the yeast (I re-hydrate it with some nutrients in advance). The krausen starting building up fast, and overflowed the airlock in a couple hours, despite giving plenty of head space. I had to fall back to having an airtight runoff hose connected to the bung and a giant pot of distilled water. Now I'm at my FG after just a few days, and the airlock I've now put in place only sputters about once a minute.

Would it be OK at this point to rack the beer, add some liquid sugar, stir it up, then bottle it? The beer smells fine, and I'd let it bottle age for at least 5 weeks. I'm wondering if this accelerated fermentation strains the yeast too much and will create undesirable effects.

Thanks!

 

[QuercusMax]

What was your OG?
What was you FG?
What was the temperature of the beer?

I would give it at least another few days to clarify before bottling.

 

[WoodlandBrew]

Much of the time fast fermentation is due to high fermentation temperature over 70 degrees, which I'm sure you know can add some unwanted charactor. However, if you were able to control your temperature and still had it run that fast it's probably just healthy yeast and nothing to worry about.

I wouldn't package it until you know it has really stopped fermenting. (reading two days apart are the same) Many people will let the beer sit on the cake for at least a week so the yeast can clean up some of the off flavors before packaging.

 

[ACbrewer]

fast or slow ferment, doesn't matter, TASTE it, because in the end that is what matters.

It is not uncommon for the beer to have something like 90% conversion in a few days. It is usually a few more to get that last 2 or 3 points of gravity. I'd say let it sit and do as Woodland suggests - take a couple readings a couple of days appart

 

[peterj]

Yeah, 3 days sounds pretty normal to me. Usually the majority of fermentation will be done in about 3-5 days. I wouldn't bottle it yet though, because there is some fermentation still going on and the yeast are also cleaning up some of their byproducts. I usually leave it on the yeast for at least 2 weeks.

I have heard that honey takes a long time to ferment out completely (compared to beer). Also, I don't think you really need to add that much yeast nutrient when making beer. Malted grains contribute a lot of nutrients that honey doesn't have. I've never used yeast nutrient in my beer. Well I add it to starters sometimes if I remember to. And to cider. Anyway good luck!

 

[dogbert]

Thank you all.

OG: 1.062
FG: 1.019

The desired FG is 1.018, so yeah, it's close to finishing. I forgot that the grains would provide additional nutrients, which I why I always add them to my mead.

The yeast was pitched at 69 degrees. I have a pretty big wort chiller, so I was able to stabilize the temperature of the wort to the temperature of the storage cabinet before pitching.

 

[dogbert]

I have heard that honey takes a long time to ferment out completely (compared to beer).

It typically does take quite some time, hence why I'll often use Lalvin EC-1118 to make sure it kicks off to a good start and completes to dryness. Even with the staggered nutrient additions, I sometimes have to add the honey in stages, as the osmotic pressure for stronger meads (ie: 16%+ ABV) can be too much for the yeast.

 

[sweetcell]

how much yeast did you pitch? if you pitched a lot, there would have been little lag time since little to no growth was required, so fermentation took off quickly.

and sometimes a fermentation is just faster than other times. 3 days, while fast, isn't unheard of.

 

[BigFloyd]

Thank you all.

OG: 1.062
FG: 1.019

The desired FG is 1.018, so yeah, it's close to finishing. I forgot that the grains would provide additional nutrients, which I why I always add them to my mead.

The yeast was pitched at 69 degrees. I have a pretty big wort chiller, so I was able to stabilize the temperature of the wort to the temperature of the storage cabinet before pitching.

At what temp did you keep this batch after you pitched yeast on it? If it was at 69-70*F air temp, I'm afraid that's too warm for most ale yeasts. What yeast did you use?

 

[dogbert]

The fermenting wort stayed at about the pitch temperature, roughly 69 (room temp at my place).

 

[bethebrew]

The fermenting wort stayed at about the pitch temperature, roughly 69 (room temp at my place).

well that's where you are probably wrong. it's surprising just how much warmer the fermenting liquid can be. 5 degrees, perhaps as much as 10 deg F over ambient.

otherwise hey it's an ale and you are still in the not too high range at 74F?, it may be a little estery and have a few fusels, but should be just fine for the most part. next time if you can get your actual ferment temp low 60s (high 50s ambient) you will have a cleaner less fruity less fuselly ale.

 

[dogbert]

Do you just mean the initial fermentation temperature, or the temperature across the first two weeks, before it gets bottled?

 

[KepowOb]

Do you just mean the initial fermentation temperature, or the temperature across the first two weeks, before it gets bottled?

The first 3-5 days are the most important. Once active fermentation is done, you can let the temps rise a bit... Plus the exoteric nature of the fermentation is over at that point, so if your room is at 70, the beer will be around that as well.

I started controlling fermentation temps with my second batch, but I started too late. I panicked when I saw it hitting 78 and put it in ice water, but it was 2 days in at that point, and it didn't turn out well at all. Since then I've kept the beer below 68 for the first week, then let it rise to room temp (74) and I haven't had any off flavours.

 

[peterj]

the exoteric nature of the fermentation is over at that point

Yeah after the first few days the beer gets really philosophical and hard to understand.

Sorry, I know you meant exothermic, but I couldn't resist!

 

[ny101]

Also, I tend not to state the FG until I know what it is.... maybe I would call what you have a target FG. I've had beers go a few points lower using the same process (as far as I can tell) or finish higher for no particular reason. Yeast is a tricky organism, and a lot of it has to do with selection (especially if you decant a starter, harvest it or propagate in any manner).

I think most people recommend to take gravity readings 3 days apart to confirm you have reached FG. So go away, come back in 3 days and if your readings match, primary fermentation has occurred, and you are probably in clean up mode. At this stage I would leave it for another few days, and then take a sample to see if you notice any obvious off flavors.