Lactose - Unfermentable

I have a sweet stout recipe with 1 lb of lactose per 5 gallons of beer.  I cannot find how to make this unfermentable - beer smith is treating lactose as if it were fully fermentable and adding it to the alcohol and subtracting it from the finished gravity.  It should not add anything to the alcohol content and it would bump up the F.G. by 1.006; while also adding to the S.G. appropriately.  Does anyone know how to change this?  My sweet stout is going to be much weaker than I originally anticipated...

Thanks!

Are you kidding? Does the people who make this software even brew beer?

I add lactose as an adjunct and not a sugar.  In my recipe, there is 1lb lactose.  There is a slight increase in estimated ABV (10.0% --> 10.5% on my imperial stout) and estimated final gravity (1.029 --> 1.030).  I would think the final gravity would be a few points higher.  I don't know how right these are but seems to be OK.

Research in using Saccharomyces cerevisia to ferment lactose in cheese whey byproducts for fuel have proven beer yeast strains lack the enzyme to effectively ferment lactose.  But they do ferment some.  They are just not good at it.  There are some mutations that tend to do better but still not useful.

The longer the yeast is held at fermentation temperatures with lactose, the more they are able to ferment.  If I were a math wiz, I would do more research in how effective beer yeast is in fermenting lactose (I think it is 2%) then use the fermentation times to estimate the alcohol contribution as well as the gravity changes.  But I am not and O don't write brewing software..  Well maybe a little.

Cheers!

Adding lactose as an adjunct in the software doesn't give the correct results either. 

Currently, Beersmith shows the correct OG value when lactose is added as a sugar, but the Estimated FG and ABV will be poor estimates.

Since this issue was identified back in 2004, are we to assume Beersmith will never calculate lactose properly? 

Maybe it will work in the phone and tablet version..

In the meantime, the free beer recipe calculator at hopville.com outputs the correct values when using lactose. 

I was surprised to find this bug and it created some confusion in the fermentation process before I realized it was a bug. 

After searching the forum for answers, I was even more surprised to find out someone brought this issue up in 2004 and nothing has been done about it since then.

  mad face!

I made this point to Brad a few months ago. He said that it would be fixed in the next version of beersmith. 

That's good news.  Any word on maltodextrin being calculated properly with an update?  Currently, it adds no gravity to the recipe which is false. 

Any update on this?  I noticed this problem also while making a sweet stout.  My OG was 1.064 and after 3 weeks in it was only 1.038.  I have 1 1/2lbs of lactose in my brew but according to the abv calc my brew will only be 3.5abv.  I didn't realize at first that the lactose was adding so much estimate abv, when it really shouldn't.

fury556 said:

Any update on this?  I noticed this problem also while making a sweet stout.  My OG was 1.064 and after 3 weeks in it was only 1.038.  I have 1 1/2lbs of lactose in my brew but according to the abv calc my brew will only be 3.5abv.  I didn't realize at first that the lactose was adding so much estimate abv, when it really shouldn't.

Click to expand...

It has been said this will be fixed eventually. 

However, your beer is probably going to be bad.  You might be able to save it by boiling and cooling some DME and adding it to the fermenter.

Embarrassingly enough, this is still not fixed.  :'(
There is probably a way to fix this by yourself, adjusting the Potential and Yield. I have no idea what the correct numbers are.
Do you?

BruuLog said:

Embarrassingly enough, this is still not fixed.  :'(

Click to expand...

Uh, embarrassingly enough, it has been addressed. 

There is probably a way to fix this by yourself, adjusting the Potential and Yield. I have no idea what the correct numbers are.
Do you?

Click to expand...

Why, yes I do... At least two methods.

Within an existing recipe you can double click the ingredient to get the specs window. In the properties column on the right hand side, you'll see a check box to make the item Not Fermentable.

In the Grain (fermentables) ingredient list, you can double click the ingredient to get the same spec window. Again, the check box is on the right side, under Properties.

brewfun said:

BruuLog said:

Embarrassingly enough, this is still not fixed.  :'(

Click to expand...

Uh, embarrassingly enough, it has been addressed. 

There is probably a way to fix this by yourself, adjusting the Potential and Yield. I have no idea what the correct numbers are.
Do you?

Click to expand...

Why, yes I do... At least two methods.

Within an existing recipe you can double click the ingredient to get the specs window. In the properties column on the right hand side, you'll see a check box to make the item Not Fermentable.

In the Grain (fermentables) ingredient list, you can double click the ingredient to get the same spec window. Again, the check box is on the right side, under Properties.

Click to expand...

Thank you for your help. It works.

PS! "addressed" is not "fixed"

BruuLog said:

PS! "addressed" is not "fixed"

Click to expand...

Almost nothing in homebrewing is fixed.