Beer Forum

Would someone in the know mind filling me in on what the harvest date should represent in the repitching slurry section of Jamil's fantastic calculator?

Here's an example that highlights my confusion: I'm going to be repitching some Wyeast 1098 for a second batch of Northern English Brown either this weekend or next (the batch was brewed a week and a half ago, I'm only using a primary fermenting vessel). If I enter the date I harvest from my carboy regardless of which weekend I keg this batch, I would have the same viability factor for yeast that's been sitting under my beer for an extra week.

What am I missing? Is the date a theoretical one from when primary fermentation is over, or is the calculator designed for repitching top cropped yeast?

What date do I enter to get the number the Pope intended to give for this situation?

Thanks For The Help,
Evan

I would say that in general it represents the date you remove the beer from the cake, wash (if that's part of your procedure), and prepare/store for later use. If you leave a portion of beer behind and store it in fermentation conditions, I'd say it refers to the day you remove that portion and ready it for pitching. If you don't store it, and you immediately pitch into new wort, that would be the date of harvest. Obviously there are plenty of possible variables her, but addressing the all in the calculator would be impossible. considering that Jamil, as far as I know, harvests from the bottom of his primary fermenter and doesn't top crop, his harvest date could apply to both methods....man that seems like a wordy response.

I got this in a PM from Jamil:

The harvest date is approximately once the yeast has flocculated and fermentation is 100% complete. A few days one way or the other is OK and is within an acceptable margin of error.


(Thanks for the help, Pope.)

J.Brew wrote:I would say

Well I took a stab at it anyway.

It was a good stab. The real trick is to use a consistent method and to adjust your process one way or the other based on success/failure. Maybe you increase the amount or decrease, based on taste. The numbers are more of a marker to help keep you consistent.