Pitching rates?

Another newbie question that has probably been asked a thousand times on here..

I've been hearing things about "pitching rates" and "starters" and all kinds of alternative ways to pitch your yeast. I've only got a couple brews under my belt, but I've just pitched the whole vial by itself into the wort and haven't had any issue thus far.

I guess my question is, what exactly are pitching rates, and why is it preferable over just dumping the vial as it comes?

For ales, the "proper pitching rate" is .75 million cells per milliter per degree plato. I forget what the pitching rate is for lagers because I don't brew them, but it's a lot more than for ales. Degrees plato = roughly OG/4. So, for a 5 gallon batch of ale with an OG of 1.060 you would need. 60/4 = 15 degres plato x .75 million x 18925 milliliters = 213 billion yeast cells. A vial or smack pack only contains about 100 billion cells. So in this instance, if you just pitched one vial without a starter you would be underpitching by about half.

The purpose of making a starter is to increase the cell count so that you have the right amount of yeast for the gravity beer that you are brewing. Can you make good beer just using a vial without a starter? Yes. But the beer will turn out better if you use the right amount of yeast.

Long answer: There is a great book called "Yeast" written by Chris White (of White Labs) and Jamil Zanisheff (spelling?) All you want to know and more about yeast and fermentation.

Shorter answer: You will get better beer if you pitch a sufficient amount of healthy, viable yeast, because the yeast will not be stressed and will not produce as many compounds which lead to off-flavors. This isn't necessarily about producing good vs. bad beer, but rather about how to make your good beer better. Jamil has a website at www.mrmalty.com which can help you with this, too.

pitching enough healthy yeast ensures a healthy fermentation and thus a better beer. check out this site for some good info on pitch rates and starter size. also, as Pappers said, the book, 'yeast' is a great source of info.

Tidwellc said:

I've just pitched the whole vial by itself into the wort and haven't had any issue thus far. ...

Click to expand...

Yeast starters and pitching rates are the answer to a question you haven't had yet.

There comes a time in every homebrewer's career where they've determined they can make beer, and it's time to buckle down and make better beer. Until that time, just have fun and do it any way that suits you.

BBL_Brewer said:

A vial or smack pack only contains about 100 billion cells. So in this instance, if you just pitched one vial without a starter you would be underpitching by about half.

The purpose of making a starter is to increase the cell count so that you have the right amount of yeast for the gravity beer that you are brewing. Can you make good beer just using a vial without a starter? Yes. But the beer will turn out better if you use the right amount of yeast.

Click to expand...

But then, is it possible to overpitch? Or am I just trying to make sure I've got more than "the minimum".

It's really hard to overpitch. Maybe by pitching a low og beer on a huge yeast cake its possible.

With a starter you are just trying to ensure you have a lot of healthy yeast so they are not stressed during the initial fermentation and won't wear out before terminal gravity is reached.

Alright, it's making some more sense to me now. Thanks!

passedpawn said:

Yeast starters and pitching rates are the answer to a question you haven't had yet.

There comes a time in every homebrewer's career where they've determined they can make beer, and it's time to buckle down and make better beer. Until that time, just have fun and do it any way that suits you.

Click to expand...

I agree with this observation on the evolution of a homebrewer.

As mentioned above, for ales 0.75 million cells/ml/degree Plato is what White and Zainasheff suggest in Yeast. Lagers get twice that amount, especially if fermented in the coldest part of their temperature range.

It's possible to overpitch but the bigger threat is underpitching. I generally use Mr. Malty to calculate starter size when using liquid yeast, or to determine the amount of slurry to use when re-pitching.