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Old 09-22-2012, 01:21 PM   #1
Dec 2009
Charleston, South Carolina
Posts: 40
Liked 1 Times on 1 Posts

Hi there. I've read many posts regarding when to add the Lactose, but still am not getting an answer to the questions I have. So, here we are...

I made the below clone of a Young's Double Chocolate Stout. The first time I made this, I added the lactose at the start of the boil. It didn't come out super sweet at all. Which brings me to question 1:

Can you boil the sweetness out that you're trying to capture?

After reading other posts about this, I now know to do it at then last ten minutes or so, which I aim to do... next time.

This go around I up and totally forgot to add it at all. I'm about a week and a half into the fermentation and am about to transfer it to a secondary. Before doing that I pose question 2 & 3:

I read that you add it at any stage, but is it better to add the lactose at the secondary or the kegging stage?
Despite what post boil stage it is added, should the amount be changed?

In trying to figure this all out for myself instead of on the boards, my brain got to thinking and giving me more questions, 4 & 5:

Is the sugar in chocolate fermentable?
If the answer is no, then could I just use more semi-sweet chocolate at the secondary instead of the unsweetened bakers chocolate?

I'm hoping a oversight like this can lead to a happy surprise and a tweak to this recipe.

Thanks to anyone who can help!

Young's Double Chocolate Stout

% Amount Name Origin Potential SRM
66.7 8.00 lbs. Marris Otter Great Britain 1.038 2
16.7 2.00 lbs. Crystal 55L Great Britian 1.034 55
8.3 1.00 lbs. Chocolate Malt Great Britain 1.034 475
6.3 0.75 lbs. Milk Sugar Generic 1.030 0
2.1 0.25 lbs. Roasted Barley Great Britain 1.029 575

Potential represented as SG per pound per gallon.


Amount Name Form Alpha IBU Boil Time
1.00 oz. Fuggle Whole 5.00 19.7 60 min.
1.00 oz. Goldings - E.K. Whole 4.75 7.5 25 min.


Amount Name Type Time
0.50 Oz Irish Moss Fining 15 Min.(boil)


White Labs WLP002 English Ale

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Old 09-27-2012, 05:44 PM   #2
Dec 2009
OFallon, IL
Posts: 469
Liked 28 Times on 25 Posts

I'm curious about when the best time is to add the Lactose in the boil so I hope you get your questions answered soon Also, should you always use a whole pound? When would half a pound be more appropriate? OR does it just depend on personal taste?

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Old 09-28-2012, 01:43 AM   #3
Jul 2011
Alpharetta, GA
Posts: 132
Liked 3 Times on 3 Posts

I always boil mine the last few minutes. And for using a whole pound I only use a half in my session stout (og is around 1.04) for anything larger I'd use a whole pound.

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Old 09-28-2012, 04:28 AM   #4
Mar 2012
Broomfield, CO
Posts: 86
Liked 13 Times on 10 Posts

For lactose, it shouldnt matter when you add it to the beer. I for one add it at flame out to make sure it has time to fully dissolve in the wort.

To get an idea of how lactose is going to affect your beer, try tasting it. Notice how it isnt very sweet for raw sugar, but is more mildly sweet and creamy/rich. Thats what your adding to your beer with lactose. Not so much sweetness but body.

As for how much to add, a good rule of thumb is no more than 5% of your total fermentables (i.e. 1lb of lactose to 19lbs of grain/DME/honey/etc)

ETA: looks like your recipe has a 12lb fermentables bill, so .75/12= 6.2% is lactose. Close enough.

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Old 09-28-2012, 12:52 PM   #5
biochemedic's Avatar
Jun 2010
Carnegie, PA
Posts: 2,220
Liked 248 Times on 187 Posts

I think you can add it at any time. I actually use it in my cider to get a bit of sweetness and still be able to bottle condition, and I do that at bottling along with the priming sugar. I just added some to my pumpkin ale, and did that at kegging time too.
Packaged: Fruitcake Old Ale
Primary: 15 Min Pale Ale (Waimea hops), Unoriginal clone (hoppy session mead)
Secondary: Why do I keep this line here...?
Bulk Aging: Simple Cyser '15, Cocobochet, Wild Cider (2014 & 2015)
Planned: So many ideas, not enough time to brew them....

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Old 09-28-2012, 01:16 PM   #6
Dec 2009
OFallon, IL
Posts: 469
Liked 28 Times on 25 Posts

Here's something I got in another post:

Originally Posted by EdMerican View Post
I'm curious about this myself. I was planning on adding it late anyway, just as habit. Perhaps to prevent underutilization of hops like in a partial boil extract batch?

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