Author Topic: Unfermentable lactose  (Read 339 times)

Offline jpeets

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Unfermentable lactose
« on: October 14, 2018, 08:03:45 PM »
 I’m having troubles reaching my original gravity numbers I add the lactose with 10 minutes left in a boil does this affect my original gravity number

Offline Robert

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Re: Unfermentable lactose
« Reply #1 on: October 14, 2018, 08:08:58 PM »
Yep, lactose will add to your OG like any sugar, just won't ferment.  If you think your OG doesn't reflect the addition,  are you sure it's completely dissolved and mixed in,  and not sitting on the bottom when you take your sample?  Ten minutes should do it, but... it's a thought.
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Offline BrewBama

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Unfermentable lactose
« Reply #2 on: October 14, 2018, 08:28:53 PM »
If you are having trouble meeting SG you could add some Dry Malt Extract to hit today’s number. ...but you still need to troubleshoot the reasoning behind low SG.

In my brewery, ‘low SG’ is a relative term. If within a point or three I am good and chalk it up to tolerance. This is a natural process using agricultural products. Therefore, variation is acceptable. If way off, well now I got some splainin to do.

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« Last Edit: October 14, 2018, 08:57:21 PM by BrewBama »
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Offline jpeets

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Re: Unfermentable lactose
« Reply #3 on: October 14, 2018, 09:43:07 PM »
 I have an electric brew kettle when I do IPAs I’m usually getting around 70% efficiency when I’m doing my stouts with the lactose I’m only getting around 60%

Offline BrewBama

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Re: Unfermentable lactose
« Reply #4 on: October 14, 2018, 09:54:30 PM »
Can you post your recipe (ingredients and process)?  Several great brewers here will be interested in helping you understand possible reasons if they have additional information.

Are your IPA(s) ‘session strength’ while stouts ‘imperial’ or ‘high octane’?  I ask because some breweries get less efficient as grain weight increases.


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Offline jpeets

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Re: Unfermentable lactose
« Reply #5 on: October 14, 2018, 10:10:18 PM »
Ipa’s Around 5abvs stouts trying for low 7s
2.5gal brew in a bag
6lbs Maris otter
4oz brown malt
4oz choc malt
4oz black patent
10oz whole grain rolled oats
12oz lactose
 And I recirculate the mash and 152 for 70 minutes
Lactose added the last 10 minutes of the boil
« Last Edit: October 14, 2018, 10:18:55 PM by jpeets »

Offline BrewBama

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Unfermentable lactose
« Reply #6 on: October 14, 2018, 11:33:13 PM »
First thing I see is no roasted barley. Of course that has nothing to do with low efficiency but normally stout has it ...but it’s your beer and you can certainly brew it the way to want. Here’s a pretty good article on Oatmeal Stout: https://beerandbrewing.com/make-your-best-oatmeal-stout/  of course it’s just one way to go but it gives reasoning.


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Offline jpeets

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Re: Unfermentable lactose
« Reply #7 on: October 14, 2018, 11:54:49 PM »

Great quick read Thanks I got 2 great tips I’ll try next time

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Offline Robert

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Re: Unfermentable lactose
« Reply #8 on: October 15, 2018, 12:24:32 AM »
First thing I see is no roasted barley. Of course that has nothing to do with low efficiency but normally stout has it ...but it’s your beer and you can certainly brew it the way to want. Here’s a pretty good article on Oatmeal Stout: https://beerandbrewing.com/make-your-best-oatmeal-stout/  of course it’s just one way to go but it gives reasoning.


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Actually, reading tons of Ron Pattinson's historic porter and stout recipes lately, I've only found a couple that use roasted barley; they usually used pale malt with a limited percentage of some combination of amber, brown, black, crystal, and sugars.   He also says the "oatmeal" versions generally used oats at less than 0.5% --  because then they could brew just one beer and, perfectly legally, sell some of it as porter or stout and some as oatmeal stout!   (How advertising image influences your sensory perception:  discuss.) So really, you can formulate your recipe any way you like; the modern guidelines and conventions have little to do with beers just a half century ago, but are well established in their own right,  and it's your beer anyway.  These styles seem open to a wide range  of interpretation,  unless you're trying to meet comp specs.  (It seems the raw barley only got into Guinness in the 1980s.)

(The only recipe I can lay my hands on right now using roasted barley is a porter, not a stout!  So much for that distinction.)
« Last Edit: October 15, 2018, 12:33:07 AM by Robert »
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Offline BrewBama

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Unfermentable lactose
« Reply #9 on: October 15, 2018, 12:33:11 AM »

Actually, reading tons of Ron Pattinson's historic porter and stout recipes lately, I've only found a couple that use roasted barley; they usually used pale malt with a limited percentage of some combination of amber, brown, black, crystal, and sugars.   He also says the "oatmeal" versions generally used oats at less than 0.5% --  because then they could brew just one beer and, perfectly legally, sell some of it as porter or stout and some as oatmeal stout!   (How advertising image influences your sensory perception:  discuss.) So really, you can formulate your recipe any way you like; the modern guidelines and conventions have little to do with beers just a half century ago, but are well established in their own right,  and it's your beer anyway.  These styles seem open to a wide range  of interpretation,  unless you're trying to meet comp specs.  (It seems the raw barley only got into Guinness in the 1980s.)

Interesting.


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Offline Robert

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Re: Unfermentable lactose
« Reply #10 on: October 15, 2018, 01:18:47 AM »
And I thank you, Bama, for that link.  It's an extremely well thought out recipe I might put to use.  I'm anxiously awaiting the limited annual release of Great Lakes Ohio City Oatmeal Stout.   It's one of their best beers, should be year round, and they really treat it like  an afterthought.   I'll be stocking up while everyone else fights over cases of Christmas Ale.  That recipe might be even tastier.
Rob Stein
Akron, Ohio

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Offline TeeDubb

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Re: Unfermentable lactose
« Reply #11 on: October 15, 2018, 03:56:03 AM »
Getting back to your original question, it may help to measure your OG before and after you add the lactose.  A pound of lactose in 5 gal of wort should add about 6-7 points of gravity.  It will also raise your final gravity by about the same amount.  For your efficiency calculations, I think you mean your 'mash conversion efficiency'
and if that is what you care about, I would omit the effect of the lactose addition. 

Note: most brewing calculators, like the one on Brewer's Friend, can include un-fermentable sugars like lactose in the mash efficiency calculation.  All things equal, adding lactose to the formula they use will drive down the reported mash efficiency simply because the sugar in lactose is un-fermentable.  So, a little confusing if you're trying to compare your mash process efficiency on a IPA vs. a stout with lactose.