How much yeast do I need?

[sictransit701]

My recipe expects 11 gallons of wort at 1.060. How much dry yeast do I need? I’m using Fermentis k97 packets. I’ve used different yeast calculators and they all same something different. Then there are guys in my homebrew club who say something different. It’s all confusing. I plan to sprinkle 4 packs.

 

[mac_1103]

My guess is that the calculators are giving different results because the people who wrote them all have different opinions about the correct pitch rate. Recommended pitch rates for ale yeasts can range from 0.35M cells / mL / °P up to 1.25 M cells / mL / °P. If you went by Fermentis' TDS, you would probably use 2-3 packs for 11 gallons of mid-gravity wort but I think most folks here would say that you're smart to pitch 4 instead. That will give you at least 0.75M cells / mL / °P.

 

[hotbeer]

Pitch dosage for K97 and I think most other ale yeast from Fermentis is 50 to 80 g/hl. That's about 1.89 - 3.02 grams per every gallon of wort in the FV.

So for 11 gallons you'll be good with at least 20.79 grams of yeast. You might be better if you use more. But only your experience will tell that.

For home brewing pitching too much will never be likely to have a bad effect. Pitching too little might. But I'm still a little uncertain what that is other than slow to get going. Maybe it's a factor for things getting stalled. Maybe it's more a factor for big beers.

 

[hottpeper13]

Never used that yeast but would think the fermentation temp would be low, say 55* to 60* at pitch then upped to 64* then to 68*. for those types of ale (German) you need to pitch more. Maybe some calculators take that into the logarithm. Me, I'm cheap(read frugal) and would make a 2L starter with one pack,chill , decant and make a vitality starter on brew day with 1 qt of 10 min boiled and chilled wort. Pitch the whole thing.