Over-pitched yeast- how to avoid autolysis?

I am doing my first batch with a yeast starter. I harvested yeast from a commercial Belgian trappist ale, built it up for a couple of days, cold-crashed it, decanted off the majority of the mini-wort and am getting ready to pitch it.

Sadly, I'm realizing that the size of my starter isn't what I was hoping for. I'm wanting to do a bigger beer than this meager amount of yeast will get rolling. So, I'm about to throw caution into the wind and follow up my trappist yeast starter with a boring old Safbrew T-58 dry yeast package, perhaps perhaps 3/4 of the package. Going to sacrifice the possible trappist yeast strain flavor for a stronger beer.

So, this probably higher amount of yeast will speed up fermentation (yes, using a blow-off tube). What I'm worried most about is getting too much autolysis (or some other symptom I don't yet know the name for).

What can I do to mitigate the effects of pitching too much yeast? I was thinking about moving up my racking schedule, but I'm not sure that'll do it.

Topic pitching autolysis yeast homebrew

Category Mac


Autolysis in homebrew is largely a myth. The reason being that a five gallon batch in a carboy or bucket doesn't have the weight or geometry to compress the the yeast the way a 100 gallon or more conical can.

On the other hand, you can still get off or wrong flavors from pitching too much yeast.

When harvesting yeast, it typically takes time and several step ups to get to a viable amount to pitch. It is unlikely that pitching a "couple of days" of a harvest plus one packet of dry yeast will be "over-pitching", but that is dependent on the starting gravity. 1.055 is about right for one 11 gram packet.

T-58 is 10 grams, and if you didn't re-hydrate, you might lose 25-30%, so adding the harvest might actually be what you should be aiming to hit, but again, can't really comment without the starting gravity and whether or not you re-hydrated.

If you have not yet pitched the second yeast, I'd give the first yeast a day or two to see if it takes off. If you had at least some growth in your harvested starter, then it will likely take off and do fine. Under pitching on a Belgian shouldn't hurt too much, but will add some fruity esters, which can be mitigated with lower temps and time.

T58 is a solid yeast and will work if the harvest doesn't take off. Pitching both probably won't matter much but the T58 will likely dominate. It's hard to make an accurate statement without knowing the gravity and quantity from the harvest. You can check pitching rates at mr malty


It's common for 'big' beer recipes to call for 2 bottle of white labs yeast (in a starter), so depending on how big your starter is you might be fine. I find that about 100-150ml of an active (foams when shaken) starter will work great for 20L batch in the 1.050-1.060 range.

Also I don't think that over pitching isn't such a bad thing. People sometimes put fresh on a the yeast of the previous batch, and AFAIK thats works well if the yeast is clean.

So I think that an extra 7.5 grams of dry yeast is not going to be an overpitch.

Maybe somebody else can comment on the flavor of T58 vs. the bottle dregs you're using?

About

Geeks Mental is a community that publishes articles and tutorials about Web, Android, Data Science, new techniques and Linux security.