Sluggish Starter

[Gilbey]

I made up a starter on Friday with about a quart of 1.040 wort and some liquid ale yeast. There is some activity, but it is sluggish, like it just doesn't want to get up and go. I have the starter in a glass growler with an airlock and in my bathroom where the ambient temp is 70F. I have done dozens of starters in this same manner, but this one seems different. Its a yeast I have never used, so I want to do whatever I can to save it.

Any ideas?

Thanks

Alan

 

[Yooper]

It's sounding ok to me- even if it's sluggish, if it's going that's fine. Your goal here is yeast reproduction, and it sounds like it's happening.

 

[Gilbey]

Should I expect visable activity to pick up? If it's sluggish now how is it going to work when I pitch it on Wednesday?

Alan

 

[Yooper]

Should I expect visable activity to pick up? If it's sluggish now how is it going to work when I pitch it on Wednesday?

Alan

Well, it really depends on the amount of fermentables, the yeast strain, the amount of healthy yeast cells, etc. I think if you get good reproduction in the starter it'll be fine. You could always step it up once between now and brewday, to ensure enough yeast cells.

 

[Koduolu]

make sure you are getting it moving too, if you dont have a stir plate, swirl it around every chance you get.

 

[kanzimonson]

How old was the yeast? The older the package, the longer it takes to get going. Go with your gut on it - if you don't feel like you have enough yeast activity, chill it and see how much yeast you actually have.

 

[Gilbey]

I have been shaking it every few hours when I am home. It seems that a LOT of the yeast is settling out very quickly. There are a few small groups of bubbles on the top, and I am getting a bubble through the air lock every 15 seconds or so.

 

[kanzimonson]

When the yeast has been settling out in a starter, that pretty much indicates that they're done growing. You won't get any more cells by fermenting longer. Go ahead and cool it and then evaluate.

 

[Gilbey]

Thanks for the info and help.

I still have a LOT to learn, but why would the yeast be done growing if presumably there is still fermentable sugars in the starter? Could it have eaten through all that sugar in such a short time with only limited fermentation noted???

Alan

 

[devilishprune]

Starters ferment quickly because of the large amount of yeast relative to the small amount of low gravity wort. Usually, I don't see a krausen on mine. Your starter is probably fine if you see a layer of floculated yeast.

In the future, you might want to consider using a piece of sanitized Al foil on the top of your growler, since it will allow more O2 to get in. Yeast need oxygen to grow, so you want them to have as much as possible.

 

[kanzimonson]

You also need to be aware of the yeasts' life cycle. The simplified version: when they're introduced to wort, they sense the abundance of nutrients and will reproduce until an optimum population is reached. At that point they begin fermenting. Sure, there's probably some reproduction that continues through to the end, but in general this is what to expect.

Fermentation = eating. Look at humans - even though we eat all the time, we're not always reproducing, right? =D