Author Topic: Yeasts and Quantity  (Read 2167 times)

Offline Manuj

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Yeasts and Quantity
« on: June 25, 2018, 03:53:53 PM »
Hi guys,

I noticed a weird thing with BS2.3, or at least this is what I think.

When I brew with my Braumeister 50l, I split the batches (so that buckets fit in my fermentation fridge).
I sometimes make some tests because I have 2 buckets, dry hop most often, but more recently I am testing a substitute to WB-06 (that I think I dislike but my friends loved the beer) in the second bucket.

So here's what I did :
=> opened the 50l recipe
=> added the second yeast (so that both yeast will appear in order list)
=> I am very aware that BS is not ment to handle both yeasts, within session tab, I put information in comments section and consider BS very useful when brewing, and until fermentation starts (for water calculation, stock, ...)

Then what I noticed :
As I am now fermenting those 2 buckets with those 2 different yeasts. The two buckets did not have the same gravity when I checked today, so I came back to BS to check that out.
=> if I change quantity on those yeasts (switching/selecting yeast by "zeroing" quantity or not), this has no effect on attenuation calculation (final gravity stays the same).
=> I have to delete yeast (keep only one at a time) to have the final gravity correctly calculated.

So my overall question : is it normal that putting a yeast to "zero" quantity will anyway keet that yeast for final gravity calculation ?
If I put zero quantity to a grain, then it is not used for gravity calculation, same for hops.
If this is normal, I would recommend to inform the end user that "0" quantity for a yeast is not acceptable.
Maybe there is a reason for brews using two yeasts in one bucket (for some sour beer for instance) that I don't understand. But right now it looks weird to me.

Thanks for any clarification, and help me understand how BS handles yeasts.

Offline Oginme

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Re: Yeasts and Quantity
« Reply #1 on: June 25, 2018, 07:31:44 PM »
As you are building a recipe, BeerSmith uses a default value for yeast attenuation (I think something around 70% or 75%) for initial calculations.  When you define your yeast that you will use, the program then uses the apparent attenuation defined in that yeast profile. So, I believe that when you set your yeast quantity to zero, it refers to the default value for giving a FG target.
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Offline Manuj

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Re: Yeasts and Quantity
« Reply #2 on: June 26, 2018, 05:17:04 AM »
Since I have 2 yeasts (Y1 and Y2), one with quantity set to zero (Y1), the other to 1 pkg (Y2), I was first assuming that Beersmith would only use attenuation of the Y2 profile. But the reality is that I have to manually delete Y1 to get that calculation correct with Y2.

This is fine with me that if no yeast is defined, or all to zero quantity, then the program would use the default attenuation.