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Brewing Topics => Brewing Discussion => Topic started by: GlediBr on October 11, 2017, 04:39:28 AM

Title: Adjusting the attenuation in BS
Post by: GlediBr on October 11, 2017, 04:39:28 AM
Hello everyone,
im getting a super attenuation from the Danstar Nothingham Ale dry yeast. second my measurements is about 91% :0
Beersmith Standard assumption is ca 75%. due to that i?ve got a predicted FG of 3.2 and in reality is 1.2.
Can i just add the new attenuation and save it for Danstar? I believe that this attenuation would not be allways the same as well right?
I know that for the final calculation BS take into account the mash Profile, etc.  I dont mind having a 0,3% +- but having 1,5-2% higher or lower ABV is already something...
thanks in advance for any tips
Title: Re: Adjusting the attenuation in BS
Post by: Oginme on October 11, 2017, 05:28:45 AM
The standard assumption is 75% before you add the yeast to the recipe.  Once you add the yeast strain to the recipe, the program uses the maximum attenuation for that yeast.

When you say you got 91% apparent attenuation, on what grist did you achieve that number?  The addition of simple sugars to a recipe will skew the apparent attenuation of any yeast strain higher than normal, since the simple sugars ferment out completely.  The other thing to check is to make sure that you don't have any contamination by a wild yeast or bacteria which may be consuming many of the more complex sugars that the yeast will not touch.  This too will skew your attenuation numbers higher than the yeast can normally produce.