Under pitching ?

[Irena]

hi,i brewed a batch of brown ale 2 weeks ago and then pitched the yeast,the airlock started to bubbling vigorously after a day.
there was no airlock activity from 3 days ago,so today i opened the lid of fermenter and pour a vial of yeast again and swirled the fermenter,i see the airlock avctivty again like two weeks ago (maybe a bit slower) when i pitched the yeast for the first time.i know the beer didn't finished fermentation.did i ruin my beer by adding too much yeast ?
should i let it sit in fermenter for another 2 weeks instead of pitching another yeast?
thanks.

 

[rocketman768]

Fermentation is typically only 4 days to a week at around 20C. Your beer was likely done fermenting after two weeks, and there was no need to add more yeast. But, I don't think you ruined your beer by adding more yeast. Let it stay another 2 weeks and then bottle it.

 

[Jsmith82]

What was your original gravity reading and where was your gravity when you decided to pitch another vile of yeast? I'm guessing your beer was fine; highly doubting a second vile was needed, especially for the type of beer.

 

[Skarekrough]

Could be an issue with the temperatures.

I have found that with some ales the yeast will be good for a few days and then peter out and not complete. Re-pitching will kick it over again but produce the same results.

But if I use a brew belt I do find that the single pitching will get it where it needs to be.

 

[Irena]

What was your original gravity reading and where was your gravity when you decided to pitch another vile of yeast? I'm guessing your beer was fine; highly doubting a second vile was needed, especially for the type of beer.

OG was 1.050 and i think the FG when i pitched the second yeast was 1.025 (or 1.015 because i didn't write it).

 

[Jsmith82]

Well at this point there is no turning back; I'd just let it go for another couple weeks and see where you end up. +1 with Rocketman, you'll end up with beer and that's the important part!

Consider taking multiple accurate gravity readings in the future to gauge where your fermentation is at to avoid making an illogical decision and post your issue here first before doing anything you're not confident in 100%.

 

[BrewBeer4fun]

Hey All. I brewed yesterday for the first time in 5 months and finally brewed my first batch at my new home but I know for a fact I underpitched and now I need advice.

I make a batch size of 11.75 gallons and because I had no more slants left of even a starter going, I was forced to use dry yeast which I thought I had at least two packets of Danstar Nottingham sitting in my fridge but it turns out it was only one packet.

So, I was forced to do one of two things, make a starter from one packet and make my newly brewed wort to sit around waiting for days on yeast, or simply pitching the one packet of Nottingham between both buckets of 5.5gal each which is what I did.

Now I have two 5.5gal buckets with a half a packet of dry yeast per bucket and it's freaking me out.

I should note that this is an America Pale Ale with a low OG of 1.042
I usually always have a very robust starter going using my favorite 1056 Ale yeast but I had none so I made due with what I had.

The question I pose to anyone reading this would be, "What are my options?" I have no more yeast at my house and would take days to overnight any.

What might this low ABV brew taste like if it was seriously underpitched?

 

[mtnagel]

What size was the yeast packet?

Mr Malty says you needed 163 billion cells and there are roughly 230 billion cells in an 11.5 g packet, so assuming 100% viability, you under pitched by about 50 billion cells (assuming you used an 11.5 g packet). I think you'll still get beer, it just won't be as good as if you pitched correctly. Now if you used a 5 g packet between both batches, well then you really did underpitch a lot.

I probably would have made a starter that night and pitched in the morning.

 

[ACbrewer]

When you under pitch, the yeast go through more generations to get to saturation (yeast will grow to some limit of cells per volume and then stop reproducing). Most common result from that is to get off flavors. Thus your beer won't be as clean tasting. These off flavors tend towards the Belgium in styles, but could be different than that.

You could pitch more yeast, but only if you do it in the first 12 hours. After that, you probably will have the growth of all of those generations. The final ABV will be the same as if you pitched properly so no worries there.

 

[Clonefan94]

What size was the yeast packet?

Mr Malty says you needed 163 billion cells and there are roughly 230 billion cells in an 11.5 g packet, so assuming 100% viability, you under pitched by about 50 billion cells (assuming you used an 11.5 g packet). I think you'll still get beer, it just won't be as good as if you pitched correctly. Now if you used a 5 g packet between both batches, well then you really did underpitch a lot.

I probably would have made a starter that night and pitched in the morning.

Am I not reading something right? If he needed 163 Billion, but pitched 230 Billion, wouldn't he have over pitched by 50 billion? Yeast is my next step to try and narrow down in my process and figuring out exactly what I need instead of just pitching a packet or a smack pack, but it seems that every time I read something about yeast, I just get more confused.

 

[ACbrewer]

Am I not reading something right? If he needed 163 Billion, but pitched 230 Billion, wouldn't he have over pitched by 50 billion? Yeast is my next step to try and narrow down in my process and figuring out exactly what I need instead of just pitching a packet or a smack pack, but it seems that every time I read something about yeast, I just get more confused.

I think he had it backwards. I went to mrmalty (from his link) and got basically the reverse. He has the right numbers but in the wrong order in the sentence.

 

[mtnagel]

Am I not reading something right? If he needed 163 Billion, but pitched 230 Billion, wouldn't he have over pitched by 50 billion? Yeast is my next step to try and narrow down in my process and figuring out exactly what I need instead of just pitching a packet or a smack pack, but it seems that every time I read something about yeast, I just get more confused.

I think he had it backwards. I went to mrmalty (from his link) and got basically the reverse. He has the right numbers but in the wrong order in the sentence.

Sorry for the confusion. I meant that he underpitched by about 50 billion per 5.5 gal bucket.

Said another way, for his total 11 gal batch, he needed 326 billion cells, but (theoretically) only pitched 230 billion cells (this is assuming 100% viability, which is most likely not the case, but dry yeast lasts longer than liquid).

 

[BrewBeer4fun]

What size was the yeast packet?

Mr Malty says you needed 163 billion cells and there are roughly 230 billion cells in an 11.5 g packet, so assuming 100% viability, you under pitched by about 50 billion cells (assuming you used an 11.5 g packet). I think you'll still get beer, it just won't be as good as if you pitched correctly. Now if you used a 5 g packet between both batches, well then you really did underpitch a lot.

I probably would have made a starter that night and pitched in the morning.

Sorry. I had not realized that Danstar made anything but the small 11 gram packets. I used their 11 gram packet between 11.75 gallons at an OG of 1.041.

 

[mtnagel]

So you underpitched by about a third. You needed 18 g, but you only pitched 11 g. It's obviously not ideal, but I never checked pitching rates when I first started out and I still made drinkable beer. After it's done, see how it tastes, learn from it and move on (and be more prepared next time ).

 

[BrewBeer4fun]

So you underpitched by about a third. You needed 18 g, but you only pitched 11 g. It's obviously not ideal, but I never checked pitching rates when I first started out and I still made drinkable beer. After it's done, see how it tastes, learn from it and move on (and be more prepared next time ).

Hey mtnagel, thanks for the post. It really sucks that this far along in brewing (literally hundreds of all grain batches) that I did such a foolish thing but and it really sucks to have to drink (I feel compelled to) 110 beers or so with possible off flavors. I do appreciate the information though so thank you for the quick reply and valuable information.

I received 4 more packets of Nottingham 3 days after brew day but after reading a previous post that stated if it is not within the first 12 hours to not even bother, I decided not to repitch.

Thanks to everyone/anyone that replied and happy brewing!

 

[BrewBeer4fun]

OK. So I have an update to my issue. I moved the first of my two 5gal buckets to keg and force carbed using an air stone and I am very proud to report that the American Pale Ale is absolutely delicious. Not one off flavor can be detected.

I am absolutely pleased that it turned out just how it did. Thanks again to all the great and experienced brewers that responded to this post and to anyone that slightly under pitched I would say, do NOT pour out your brew until its done and you try it! It may just turn out better than if you fully pitched...

 

[Jayslay]

Some yeasts and certain styles have a change of flavour compounds when under pitched. I'm a wheat beer guy and I underpitch my hefeweizen by skipping starter off a smack pack. Gives me the esters and my beloved banana taste. I made a Wit that way however and it produced some interesting saison-esque flavors. It wasn't what I was going for so I guess I sit on the fence.