Milk Porter

[Nosybear]

If your batch is 5 gallons, the SG delta would be 41 (the points in 1 pound of lactose, apparently it hydrates and I did not take that into account) / 5 gal (the volume of the batch). That's 8.2 unfermentable points of gravity. Another hypothesis: You're off by 4 points - that's really not much, a half-pound of sugar in a 5 gallon batch. Measurements can err, the FG is a prediction so it may just be that your final gravity is just 4 points high.

 

[thunderwagn]

What @Nosybear said. Lactose is non-fermatable. You need to account for that in both OG an FG.

 

[AGbrewer]

So basically you guys are saying is to take 8.2 points off the OG and FG to find my attenuation?

If that is what you are suggesting, then my attenuation is around 75% which is more inline with the spec on that yeast.

 

[Nosybear]

So basically you guys are saying is to take 8.2 points off the OG and FG to find my attenuation?

If that is what you are suggesting, then my attenuation is around 75% which is more inline with the spec on that yeast.

Yes. The 8.2 points are unfermentable sugar. So the apparent attenuation of the remaining sugars should be the number you're after.

 

[AGbrewer]

Thanks everyone for the help. I'll try to remember that the next time I add Lactose to a beer.

 

[thunderwagn]

I think beersmith calculates the use of lactose and accounts for it if memory serves correctly. BF must not.

 

[BOB357]

I think beersmith calculates the use of lactose and accounts for it if memory serves correctly. BF must not.

You are correct. When lactose is entered in the BeerSmith database the Not Fermentable box needs to be checked. This will cause an equal increase in both OG and FG, as it should.

 

[Craigerrr]

You are correct. When lactose is entered in the BeerSmith database the Not Fermentable box needs to be checked. This will cause an equal increase in both OG and FG, as it should.

I just checked Brewfather quickly, and lactose affects OG/FG as expected.