Didn't add correct amount of yeast :(

hey all,

I've made a couple 1 gallon recipes with varying success so since I received a five gallon carboy as a gift, i decided to try my hand at a bigger quantity. Everything generally went well, except in reading the recipe, I accidentally forgot to add the right amount of yeast. So the 1 gallon calls for 1/2 packet of ale yeast and the 5 gallon recipe calls for 1 full packet. i Only added 1/2 packet and I didnt' realize until now (violent fermentation has stopped) and I've already put the airlock on. I began brew a week ago.

Should i leave well enough alone or add more yeast and re-aerate?

What's the current SG and the OG?

Leave well enough alone. Relax, don't worry, have a homebrew.

However:

Take a gravity reading. That way you can see how well the yeast is working. If you are really far from the final gravity, you may want to consider pitching more yeast.

If you do add more yeast, don't aerate. At this point, you will risk oxidizing your beer, or infecting it.

The biggest issue you may have with underpitching is off-flavors, as the yeast may be stressed. But it's not guaranteed, and something that can be helped by letting it sit for a few weeks longer, should such a situation develop.


Unless you made a really big, high gravity beer, you're probably ok.


It would help to know your recipe, and what kind of yeast you pitched.


Your first step, though, is to take a gravity reading.


CB

ahh..unfortunately I do not yet have a hydrometer..so i can't take a measurement. the type of yeast is safbrew t-58 ale yeast and the recipe incorporates the following with standard hour mash, hour boil:

pale ale grain
caramel 20
caramel 10
victory
another grain i forget

chinook hops
columbus hops
grapefruit peal
belgian candy and honey before cooling.

If the "violent fermentation" has stopped, it's probably done. Not enough yeast can be a problem, but generally, you'll see a long lag before the fermentation starts. Sounds like it took right off.

Well you could always get a hydrometer and just let it sit in the meantime. If the fermentation didn't have a long lag time you can prob assume its done. But without a reading its really all a flip of the coin

OP, some advice:

Invest the $8 for a hydrometer. Sometime, somewhere, you are going to end up with bottle bombs if you don't, since you won't know if gravity is stable.

If you're going to do 5 gallon batches of beer, make starters for liquid yeast.

Adding only half the yeast just makes it slower to kick off fermentation and gives more of a chance for wild yeasts and other nasties to get into the wort. Dry packs have a lot of yeast cells in them and you are probably fine, especially since you had a "violent fermentation"

Buy a hydrometer. Make starters. Make good beer.

What was your recipe? Im sure the half pack wasn't "ideally" enough, but it might have been plenty to finish your beer if the OG was low enough.

You'll still get beer if you underpitch yeast. It might not fully attenuate and your beer might not be as dry as you intended. It also may have some more fruity/estery tastes due to stressing the yeast a bit. Higher temps will make that more pronounced, but if you fermented cool, you might not notice much - depending on the yeast.