Pumpkin ale to secondary

[rossiski]

Brewed a sweet potato butternut squash beer 8 days ago. It is wrapping up fermentation and I am wondering if I should transfer to a secondary before I cold crash? There is a lot of trub in my primary and I'm worried about getting it cleared up

[BDawg]

Give it at least a full 2 weeks then check gravity before you transfer. Then let it sit a week there in the brite tank before cold crashing. No need to worry about yeast autolysis this early at homebrew scale. It's when the yeast gets under a lot of pressure (ie, in the bottom of a huge conical) at the commercial scale that they need to worry.
You should be more concerned that they yeast have plenty of time to clean up after themselves. I'd say that most under-attenuation issues are because of a combination of under pitching and being too eager to rack off the primary cake before its finished.
Sure, I understand you want to drink your beer. But the extra time will make it so much better than if you rack it too early.

If you are running out of beer, then the answer is to brew more so you have a full enough pipeline so you don't run out, not cut fermentation short.

HTH-

[Afterlab]

Brewed a sweet potato butternut squash beer 8 days ago. It is wrapping up fermentation and I am wondering if I should transfer to a secondary before I cold crash? There is a lot of trub in my primary and I'm worried about getting it cleared up

An easy way to avoid this is to transfer less trub into fermentation or to siphon the break out of the vessel prior to pitching yeast; this will assure lipids, fatty acids and proteins aren't available to oxidize, ruin foam creating proteins or provide food for bacteria. Unless you plan on aging this for a while or selling this to a distributor like a production brewery, you don't need to worry about the effects of trub because a typical batch of homebrew is well looked after (refrigerated) and consumed quickly by individuals who didn't spend money to consume it; not to mention those consuming your homebrew won't feel the need to post a negative review on Ratebeer or BeerAdvocate if there is a minor off flavor.

The main things I would worry about for clarity sake in this beer would be potential unconverted starch from the specialty ingredients, yeast in suspension and permanent haze forming poyphenol-protein complexes. Typically junk that has settled at the bottom of a fermentation vessel is down there because of a molecular bond with something else which caused it to be denser and heavier than the beer or those individual compounds were denser than the beer to begin with and naturally settled out. With that being said, chances are if that trub gets back in solution it will just as soon drop out of solution again.

Assuming you've used yeast with high viability and vitality, I wouldn't worry about yeast autolysis until a few days to a week after you've hit terminal gravity and you've cleaned up green beer flavors like Diacetyl and Acetaldehyde. Yeast won't begin to autolize until they've consumed their glycogen reserves and starve; thus forcing themselves to consume and weaken their own cellular structure. So to avoid all green beer off flavors, I make sure all of my beers have undergone 21 days of fermentation/warm-maturation to clean up after themselves. To achieve this your beer doesn't technically need to sit on that primary yeast cake because there is and will be plenty of yeast still in suspension (even after gelatin). If you do feel the need to go to secondary ask yourself how long are you really going to keep it in secondary? Is it worth cleaning, sanitizing and doing all that other work involved in transferring to secondary to allow it to sit for a short amount of time? I would say no. Leave it in primary and package it up within a reasonable timeframe.

Whatever you do, don't crash your beer too early because you will find yourself with off flavors that do not get cleaned up. When you add oxygen to beer after fermentation the precursor for diacetyl, a-Acetolactate creates diacetyl through decarboxylation, if you transfer and immediately crash beer under these circumstances you will definitely have diacetyl and more of it if you've used a highly flocculent English ale strain.

[rossiski]

I thought diacetyl was only a lagering issue. I can't imagine that occurring after a few days in a 30 degree cold crash.
After the replies I plan to leave my beer in the primary after fermentation is complete and then cold crash for a couple of days before kegging. It is not worth the risk of moving to a secondary for a week.

[siwelwerd]

I thought diacetyl was only a lagering issue. I can't imagine that occurring after a few days in a 30 degree cold crash.

During fermentation, yeast produce (tasteless) alpha acetolactate. This is then (towards the end of fermentation) converted to diacetyl, which the yeast will eliminate, given enough time at a warm temperature. If you cold crash before the alpha acetolactate is converted to diacetyl, this conversion can still take place but the yeast are dormant and can no longer reduce the diacetyl, so you end up with diacetyl in your beer.

[Afterlab]

I thought diacetyl was only a lagering issue.

To piggyback on what siwelwerd mentioned, every yeast strains and even bacteria like Lacto and Pedio create diacetyl.

I can't imagine that occurring after a few days in a 30 degree cold crash.

At any point when you have the precursor A-Acetolactate in the beer and you expose it to oxygen, it becomes diacetyl. So any time you are transferring beer from one vessel to another, you run that risk. To counteract that, leave the beer at warmer maturation temps for a short amount of time to allow the yeast to reduce down diacetyl to other less flavorful compounds.

You certainly don't have to do this but what I do is allow my beers to ferment/condition in the carboy for 21 days. Transfer to a keg with about 4 oz of a priming sugar/water mix and then allow to sit at room temp for 7 days to create carbonation, absorb any further oxygen and to clean up acetaldehyde and diacetyl. After that 7 days I begin to crash it in the cooler. This has allowed me to save some CO2 by utilizing natural CO2, carbonate quicker and ensure I don't have any off flavors.

[rossiski]

Thanks for all the posts guys. I checked my gravity for the third night in a row and I have hit my final gravity right on target. I am going to leave it along till I hit 14 days and then crash it. My typical routine has been 14 days in the primary and 14 days in a secondary before kegging. But after listening to the BN I wanted to quite using my secondary as much as possible. By the way I am pretty happy with this beer never did a sweet potato squash before.

[Ozwald]

never did a sweet potato squash before.

This time of year will bring out those feelings. Just wash the orange pulp off your & try not to shop on ebay for pumpkins if ya know what I'm sayin'.

Secondary is rarely needed so good work. Don't be afraid to let the temp rise a little bit for your extended primary. A lot of your yeastie friends are pooped out & hanging out at the after party on the bottom. A couple degrees is helpful for the few hard workers to clean up.