FermPro 900

[8Ball]

Picked up some FermPro 900. From the manufacturer’s website:
Product Description

(Optimum temperature 80-95°F)

This high performance distillers yeast is a popular strain at numerous distilleries. The origin is a whiskey strain well suited for Bourbon or rye whiskeys, offering excellent yields and a robust flavorful congener profile. It is well suited for normal or cooler fermentations, allowing for extended fermentation times. Works well up in the mid 20 Brix range.

Suggested usage: 1 gram of yeast per gallon of mash

So I made an all grain Irish style mash yesterday. 16 pounds in 7.5 gallons water. The usual adjuncts and conversion was optimal. I aerated the mash overnight to add O2 and to facilitate cooling.

Made a yeast starter yesterday when I started the overnight cool down to pitch temperature: 16 grams of FP900, 24 oz water, 4 oz wort, pinch of Fermax, hydrated at 85F.

Good foamy cap in about 15 minutes.

This morning (18 hours later), I pitched the yeast starter.
Temp: 75.7F (a little cool), ph 4.86, SG 1.071.

4 hours later, no yeast activity at all. Flat, no bubbles, dead. So I measured out another 18 grams of FP900, and sprinkled it directly on top of the wort. One hour later and I have a good foamy grain cap going and the temperature is rising due to an active ferment.

So, FWIW, I’ll be pitching the FP900 yeast starter soon after I hydrate the yeast from now on. Apparently this stuff likes to get right to work upon being hydrated.

[Texas Jim]

Why did you pitch so much yeast? The FermPro directions are 1 gram per gallon. You did about 2.5.

Do you get better results overpitching?

[8Ball]

Why did you pitch so much yeast? The FermPro directions are 1 gram per gallon. You did about 2.5.

Do you get better results overpitching?

I actually under pitched by a half with this yeast because of the manufacturer’s dose recommendation of 1g/G.

My OG was 1.071, I use 0.05 grams per point/gallon.
(71*7.5*0.05)=26.625 grams
26.625*1.5= 39.9375 grams is what I would pitch if I was using bakers yeast.

I do a very long, natural, open fermenter, cool down to pitch temperature with my all grains, usually 18 hours or more. This maximizes the conversion since I throw a little gluco enzyme in for insurance. Since I don’t like my wort to get infected, I throw a lot of yeast at it to discourage bacteria growth.

So far, so good. I have good, clean, on the grain ferments that finish dry in about a week or so.

[StillerBoy]

I actually under pitched by a half with this yeast because of the manufacturer’s dose recommendation of 1g/G.
My OG was 1.071, I use 0.05 grams per point/gallon.
(71*7.5*0.05)=26.625 grams
26.625*1.5= 39.9375 grams is what I would pitch if I was using bakers yeast.

What formula do you use for calculating the amount of yeast to use.. what you have stated make no sense.. and your fermenting temp is off big time, 75*F is cold for that yeast..

The company states " 1 g per gallon and fermentation range is 80 - 95*F

So that mean in my book, 7.5 -8 gr of yeast for a 7.5 gal batch, and I would ferment at 85*F, which is mid range, and usually the best range..

Mars

[8Ball]

I use 0.05 grams of yeast per point gallon. The formula is in my earlier post. The FP900 is rated for cooler temps, so yea a little cool to start, but I was fermenting outside in ambient cool weather. It worked fine, so not too cold like you assume. Lend me your book, I’m running short on TP.

[Texas Jim]

I actually under pitched by a half with this yeast because of the manufacturer’s dose recommendation of 1g/G.

I was going by their dosage recommendations on their data sheet of 1 gram per gallon of mash. I've seen your formula at brewsites, but I just go by the pitching rate they state on the package.

As long as it works.

[8Ball]

I think a lot has to do with the specific gravity. Somewhere between 2 to 4 grams per gallon.