Revisiting Lactose Intolerance

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Brooothru

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I'm trying to find any contemporaneous information relating to the use of lactose in brewing. Most data are, well, dated on the topic both from the archives of this forum as well as Reddit and other web portals. The opinions here and elsewhere are literally all over the place, and most are 3 to 5 years old (or older). Can somebody help me out?

My objective is to not cause intestinal distress to anyone lactose intolerant (a "lactard"?). I am not lactose intolerant. My wife is. Fortunately she does not drink my beer. Unfortunately for me, some of my guests, to varying degrees, are. So, cut to the chase: for those who are lactose intolerant or those who might have some academic insight into the process, how does the addition of lactose in the grain bill affect those who can't digest dairy products?

From the outset, I realize it's a question of degree, both in the level of intolerance in an individual as well as the amount of lactose in the consumed product. According to the interwebs (therefore it must be true...or not) the amount of lactose in various 'dairy' products varies from as little as 1.5% to nearly 10% by weight. I'm assuming what is meant is the weight of "sugars" in the product rather than percentage of the product's weight, but that could be wrong. My wife has zero problem with yogurt (1.5% lactose) or butter (0.6% lactose) or even ice cream, but anything more than a few tablespoons of milk in a sauce, or a bowl of 'soft-serve ice cream' (ice milk, that is) will result in an urgent need to find a porcelain rest stop.

So from a practical perspective, what is the bottom line for people who are lactose intolerant and who also have or do currently consume milk stouts or milkshake IPAs? Is it possible that either brewing yeasts or alcohol in finished beer have a mechanism to create lactase from the lactose and make it digestible? Would an enzyme like amyloglucosidaise render the otherwise unfermentable lactose tolerable?

The endgame goal is to brew a sessionable pale ale/IPA (~4% ABV) that still has body. Maybe ¼ to ½ pound of lactose in an 8# grist for a 5 gallon batch. Probably use flaked oats to some degree and possibly maltodextrin, but the concern there would be amyloglucosidaise converting 'unfermentables' to sugars resulting in higher alcohol and less mouthfeel. Also looking to produce a less-hazy beer, in the style of a West Coast IPA (i.e., not crystal clear necessarily).

Maybe this is just chasing the illusive unicorn, but hey, I've got plenty of time on my hands and a gusto for experimentation. Thanks in advance for anecdotes, advice and experiences.

Brooo Brother
 
Lactose really isn't needed for body. I'd suggest looking at your brewing water profile and your mash schedule.

It seems obvious that drinking beer with added lactose would cause issues for anyone lactose-intolerant.

Typical brewers yeast (or anything else generally in beer) do not in any way metabolize lactose, and amyloglucosidase/glucoamylase does not break it down either. Pay attention to the -ase suffix, which means it's an enzyme. Lactase is the enzyme that breaks down lactose (the -ose suffix means it's a sugar), and this enzyme is available as Lactaid and generic products. Your lactose-intolerant friends could consider using this as directed when consuming any dairy products.
 
The perspective of someone who’s became lactose intolerant in his 20s and has lived with it for almost 30 years:

At first it started with only ice cream causing me problems. I switched to frozen yogurt then to diet frozen yogurt. Then it became: as long as it was only ice cream once a month it was okay. Eventually anything with heavy cream or milk became a problem in any quantity or frequency.

Cheese wasn’t a problem for me until 5 years ago. Cheese doesn’t just give me the gastro problems. I also get nausea & migraines.

Years ago, I used to brew an awesome milk stout. Now, it would probably destroy me for a couple days.

My opinion: if you want to brew with lactose, go ahead & do it. Warn anyone you know with known lactose problems and let them make the decision for themselves.

As for your recipe, I wouldn’t put lactose in a Pale Ale. If you want to increase the body of a ≈4% ABV PA, mash around 147F & use 4 to 8oz of CaraPils or Torrified Wheat to maintain the body.
 
Typical brewers yeast (or anything else generally in beer) do not in any way metabolize lactose, and amyloglucosidase/glucoamylase does not break it down either. Pay attention to the -ase suffix, which means it's an enzyme. Lactase is the enzyme that breaks down lactose (the -ose suffix means it's a sugar), and this enzyme is available as Lactaid and generic products. Your lactose-intolerant friends could consider using this as directed when consuming any dairy products.

I wish I had taken better notes while trying to break the internet. I came across a yeast "similar to brewers' yeast" that allegedly produced lactase, and the writer questioned what effect, if any, saccharomyces cerevisiae might have in breaking down lactose, at least partially, to buffer the affects on lactose intolerant persons. The writer did site the name of the yeast strain, but gave no references, and of course I didn't write it down. One common theme from responders who self-identified as lactose intolerant seemed to be that Lactaid was an effective palliative, but wasn't always needed when consuming either a milk stout or a Milkshake IPA. Ill effects seemed to be (anecdotally) dependent more on which brand or brewery the beer came from, suggesting that varying amounts of lactose were present in different beers. The question is whether that amount was recipe specific, brewer specific, process specific or specific to the person consuming the beer. Absent any controls on the respondents, the data are meaningless in drawing solid conclusions.

Increasingly I'm concluding that lactose is likely a dead end for what I'm attempting to produce, but figured I'd run it by the braintrust here. I'll probably go with oats or maltodextrin to attempt to increase body and mouthfeel, though the inclusion of amyloglucosidaise might increase the alcohol content by making the dextrins fermentable to brewing yeast. I know that amylo is effective in attacking the 1,4 and 1,6 limit dextrins so that they can be converted to fermentable sugars, but I don't understand what effect it has on converting maltodextrin or the starches in flaked oats which have already been partially gelatinized when they were heated during the pressing/flaking process. After all, the final goal is lower alcohol with more mouthfeel. Wish me luck.

Brooo Brother
 
The perspective of someone who’s became lactose intolerant in his 20s and has lived with it for almost 30 years:

At first it started with only ice cream causing me problems. I switched to frozen yogurt then to diet frozen yogurt. Then it became: as long as it was only ice cream once a month it was okay. Eventually anything with heavy cream or milk became a problem in any quantity or frequency.

Cheese wasn’t a problem for me until 5 years ago. Cheese doesn’t just give me the gastro problems. I also get nausea & migraines.

Years ago, I used to brew an awesome milk stout. Now, it would probably destroy me for a couple days.

My opinion: if you want to brew with lactose, go ahead & do it. Warn anyone you know with known lactose problems and let them make the decision for themselves.

As for your recipe, I wouldn’t put lactose in a Pale Ale. If you want to increase the body of a ≈4% ABV PA, mash around 147F & use 4 to 8oz of CaraPils or Torrified Wheat to maintain the body.

Sorry to hear about your lactose issues. We have a few friends, in addition to my wife (and daughter, now 40) who became intolerant starting in early adulthood. We have several others who suffer and live with varying degrees of celiacs disease. Neither condition is easy to cope with. The reaction to exposure is exactly what I'm hoping to avoid, and fore-knowledge and forewarning are the best courses of prevention. I just want to avoid an unintended exposure to a guest who may not know that lactose is in my Session IPA, unlike a celiac sufferer who just assumes that the grains in beer will result in issues for them. Thanks for the suggestions. The carapils along with torrified wheat or flaked oats should work.

Brooo Brother
 
wish I had taken better notes while trying to break the internet. I came across a yeast "similar to brewers' yeast" that allegedly produced lactase, and the writer questioned what effect, if any, saccharomyces cerevisiae might have in breaking down lactose, at least partially, to buffer the affects on lactose intolerant persons.
There's no reason to add lactose if your intention is just to then break it down.
There's no "buffering" against lactose intolerance. Either there's enough lactose to cause someone problems, or there isn't.

The question is whether that amount was recipe specific, brewer specific, process specific or specific to the person consuming the beer. Absent any controls on the respondents, the data are meaningless in drawing solid conclusions.
Obviously amount is the main factor. Any added lactose is normally unchanged by the brewing process. However the effects and tolerance level are specific to the individual consuming the beer.

After all, the final goal is lower alcohol with more mouthfeel.
I'm confused why you're asking about adding enzymes when you don't want the effects they produce. ??? Enzymes produce higher alcohol, and possibly less body.
 
Would an enzyme like amyloglucosidaise render the otherwise unfermentable lactose tolerable?

I don't know if that particular enzyme can break lactose down into its constituents, galactose and glucose, but if it can, you'd probably be defeating the purpose. Yeast loves to eat glucose, and according to at least one study I read, can adapt to galactose. So you'd possibly have nothing left from the lactose (except alcohol and CO2).
 
I'm confused why you're asking about adding enzymes when you don't want the effects they produce. ??? Enzymes produce higher alcohol, and possibly less body.

By obtaining greater attenuation I hope to use less base grain and end up with less alcohol. I've had some pretty good luck with amyloglucosidaise in low alcohol/low carb clones of Michelob Ultra, et. al., using 40% fewer grains to get 4.2~4.7% ABV lagers, as well as a 7.2% Brut IPA with a 'standard' grain bill that normally would have produced a 5~6% beer. FGs have been in the 0.996-0.998 range using non-diastaticus strains like Chico, though I'm sure the harvested yeasts would test STA-1 positive with the amylo still active.

The problem with those beers as well as with commercial session beers is that they lack body and mouthfeel. They make terrific 'lawnmower beers', but what I'm trying to get is a sessionable beer that has body and taste but won't leave me stumbling and drooling if I have more than two in an afternoon on the patio this summer (in isolation, it appears).

Broo Brother
 
I don't know if that particular enzyme can break lactose down into its constituents, galactose and glucose, but if it can, you'd probably be defeating the purpose. Yeast loves to eat glucose, and according to at least one study I read, can adapt to galactose. So you'd possibly have nothing left from the lactose (except alcohol and CO2).

That's pretty much what I was afraid of, but wasn't sure of, so I thought I'd throw it out there. In fact, doesn't Sacc. cerevisiae consume glucose more efficiently than maltose?
 
In fact, doesn't Sacc. cerevisiae consume glucose more efficiently than maltose?

You could say that. Yeast has to do some work to break maltose down into glucose before using it.
 
I'm sure the harvested yeasts would test STA-1 positive with the amylo still active.
STA-1 is a gene. Adding enzyme doesn't give the yeast genes. :)

what I'm trying to get is a sessionable beer that has body and taste but won't leave me stumbling and drooling if I have more than two in an afternoon on the patio this summer (in isolation, it appears).
I feel like that's pretty much every beer I brew. Most of my brews are around 5% ABV and for my palate have good body. I never add lactose, partly because I'm lactose intolerant, but also because I don't like the texture that it adds to beer.

Do you build your water profile?
 
Because it was asked, amyloglucosidase cannot breakdown lactose - no starch or maltodextrin active enzyme can.
 
STA-1 is a gene. Adding enzyme doesn't give the yeast genes. :)


I feel like that's pretty much every beer I brew. Most of my brews are around 5% ABV and for my palate have good body. I never add lactose, partly because I'm lactose intolerant, but also because I don't like the texture that it adds to beer.

Do you build your water profile?

Yes. I start out with either R.O or distilled and build from there. Since hoarding and rationing started I've had to resort to a portable 4-stage reverse osmosis we used in our RV. Takes forever to collect 9 gallons for a batch, but worth the effort. We are on a deep well with good quality water for cooking/drinking. Ward Labs showed the following:

pH 6.8 Ca 28 ppm Mg 13 ppm Na 10 ppm SO4 5 ppm Cl 33 ppm HCO3 92 ppm Tot. Hardness 124 ppm

That report was from a sample taken in early Fall, three years ago. As with most wells there is seasonal and year to year variability in the water chemistry, though we are on a very deep well adjacent to a large protected watershed fed from nearby heavily wooded hills with variable rock strata, and is probably more stable than most water tables. We are also near mixed agricultural use land, mostly low density dairy farms and some corn and soy bean production. Makes for an interesting water profile: not horrible for most beers but not especially great for any particular ones. R.O. lets me design what I want from Guiness to Helles and anything in-between, though I prefer to add as little as possible to get in the ballpark of target.

In any event, I'm taking your advice and steering clear of the lactose. It might likely sweeten it too much anyway.

Brooo Brother
 
That's good to know. What, if any, effect does amyloglucosidaise have on maltodextrin or flaked oats or torrified wheat?

Amyloglucosidase specifically hydrolyzes alpha-1,4-linked glucose residues from the ends of starch or maltooligosaccharides (maltodextrins). It will do so regardless of the source of this substrate (i.e. barley, oats, wheat, etc). It won't affect other sources of "body," such as protein or beta-glucans. Is this what you are getting at?
 
It's worth mentioning that high chloride helps with body/fullness (70+ ppm), combined with maintaining a relatively low sulfate (< 40ppm). At least that's my strategy. I've used enzyme in a couple beers and they don't feel thin to me, but maybe your taste is different.

Your water isn't that bad as a starting point, better than my tap water.

@hopjuice_71 is 100% correct.
 
Amyloglucosidase specifically hydrolyzes alpha-1,4-linked glucose residues from the ends of starch or maltooligosaccharides (maltodextrins). It will do so regardless of the source of this substrate (i.e. barley, oats, wheat, etc). It won't affect other sources of "body," such as protein or beta-glucans. Is this what you are getting at?

The way I thought "maltodextrin powder" (available at the LHBS) worked in beer brewing was that it was only about 10-15% fermentable because a-amylase and b-amylase were only able to work on maltose and unable to hydrolyze the other 85% of the saccharides. The saccharides in barley, I believed, were primarily maltose with lesser amounts of glucose and sucrose, among others. I had assumed that the unattenuated (unfermented) sugars potentially in a mashed grist bill were the result of a-amylase and b-amylase being unable to hydrolyze all of the maltose and none of the other saccharides. I reasoned that amyloglucosidaise achieved greater starch conversion in the mash by hydrolyzing the 1,4 and 1,6 branches of the starches in barley (i.e., maltose) which would otherwise not be reached by the a- and b- enzymes. Clearly, a little knowledge can lead to erroneous conclusions. I guess that's what happens when an engineer tries to play biochemist or microbiologist.

So I see from your explanation that amyloglucosidaise "specifically hydrolyzes alpha-1,4-linked glucose residues from the ends of starch", so when I add ½ tsp to my mash the result is more glucose in the wort for the yeasts to consume, making a drier, higher ABV finished beer. The net effect would be the same if I simply added corn sugar to the boiling wort (except the saccharide would be sucrose instead of glucose).

And yes, "body" is what I'm trying to achieve, but with less grain in the grist bill and lower alcohol in the finished beer, without the finished beer having residual sweetness from unfermented sugars. My thought was that using maltodextrin (or Carapils/Carafoam) and dosing with amyloglucosidaise in the mash might achieve this without drying and thinning out the finished beer, but it looks like it would have exactly the opposite result.

Flaked oats or torrified wheat may be what I have to resort to, using, as you pointed out, the proteins and beta glucans to add mouthfeel, but at the expense of clarity in the finished beer. I usually do a complex step mash which utilizes a rest at 113F for :15 minutes, even though almost all modern grains are fully modified. Palmer talks about it, and Fix recommends, in their writings, historical step mashes with rests in the range of 113F-131F for solubilization, beta glucans, peptididase and protease reductions It's been my experience that :15 minutes at 113F benefits in liquefaction, reducing beta glucans and haze-producing proteins while not significantly reducing body or head retention. Anything in the 120F-131F range of that temperature spectrum will affect both body and head retention, according to Fix, so I rest below that range. It gives me finished beers that generally have good body, leave "notches" on the side of the glass, and pour clear out of the tap even at kegerator temperature in the upper 30s.

It looks like oats/wheat with the barley, maybe maltodextrin or more Carapils, and no amyloglucosidaise will be the path forward. I'll have to give more thought to the 113F rest, but with oats/wheat in the grist I don't want to get a stuck or channeling mash since I recirculate. Many thanks to you, @RPh_Guy and @VikeMan for the helpful insights.


Brooo Brother
 
It looks like oats/wheat with the barley, maybe maltodextrin or more Carapils, and no amyloglucosidaise will be the path forward.

I'd say you're on the right track.

I'll have to give more thought to the 113F rest, but with oats/wheat in the grist I don't want to get a stuck or channeling mash since I recirculate.

A protein rest (your 113F rest) breaks down proteins. With modern, well modified malts, that has already been done and doing that rest in your mash probably reduces body. Stuck lauter/recirc can be avoided by adding rice hulls.
 
The way I thought "maltodextrin powder" (available at the LHBS) worked in beer brewing was that it was only about 10-15% fermentable because a-amylase and b-amylase were only able to work on maltose and unable to hydrolyze the other 85% of the saccharides.
Yeah basically whatever enzymes they use (on corn starch) to make maltodextrin mainly leave chains of sugar 4 units or longer, which normal brewers yeast cannot metabolize.
The saccharides in barley, I believed, were primarily maltose with lesser amounts of glucose and sucrose, among others. I had assumed that the unattenuated (unfermented) sugars potentially in a mashed grist bill were the result of a-amylase and b-amylase being unable to hydrolyze all of the maltose and none of the other saccharides.
You mean "hydrolyze all of the dextrins."
I reasoned that amyloglucosidaise achieved greater starch conversion in the mash by hydrolyzing the 1,4 and 1,6 branches of the starches in barley (i.e., maltose) which would otherwise not be reached by the a- and b- enzymes. Clearly, a little knowledge can lead to erroneous conclusions. I guess that's what happens when an engineer tries to play biochemist or microbiologist.
The primary effect of amyloglucosidase is breaking down the dextrins, not maltose.
Whether it cleaves maltose, I'm not sure, but it doesn't matter since maltose is already very fermentable to brewers yeast.
So I see from your explanation that amyloglucosidaise "specifically hydrolyzes alpha-1,4-linked glucose residues from the ends of starch", so when I add ½ tsp to my mash the result is more glucose in the wort for the yeasts to consume, making a drier, higher ABV finished beer. The net effect would be the same if I simply added corn sugar to the boiling wort (except the saccharide would be sucrose instead of glucose).
No, the effects are not the same at all. Adding enzyme increases fermentability by breaking down dextrins. Adding enzyme would be a little similar to replacing a large portion of the grain with sugar, but that still wouldn't be the same because malt adds things besides sugar/starch.

BTW corn sugar is dextrose, not sucrose.

I usually do a complex step mash which utilizes a rest at 113F for :15 minutes
I agree with @VikeMan ...
I think this is hurting the body. I would suggest starting no lower than 131°F
It gives me finished beers that generally have good body
I'm confused why you're chasing body if your beers already have good body? It is only the beers with enzyme that lack body? I would definitely reevaluate your mash schedule, and try it without the low protein rest.

BTW oats and wheat don't necessarily cause haze.

Also BTW, using multiple and/or prolonged beta rests can help increase attenuation without needing to add enzyme. And also there are less powerful enzyme products you can use (regular amylase), but I'm not sure if those would be helpful.
 
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Yeah basically whatever enzymes they use (on corn starch) to make maltodextrin mainly leave chains of sugar 4 units or longer, which normal brewers yeast cannot metabolize.

You mean "hydrolyze all of the dextrins."

The primary effect of amyloglucosidase is breaking down the dextrins, not maltose.
Whether it cleaves maltose, I'm not sure, but it doesn't matter since maltose is already very fermentable to brewers yeast.

No, the effects are not the same at all. Adding enzyme increases fermentability by breaking down dextrins. Adding enzyme would be a little similar to replacing a large portion of the grain with sugar, but that still wouldn't be the same because malt adds things besides sugar/starch.

BTW corn sugar is dextrose, not sucrose.


I agree with @VikeMan ...
I think this is hurting the body. I would suggest starting no lower than 131°F

I'm confused why you're chasing body if your beers already have good body? It is only the beers with enzyme that lack body? I would definitely reevaluate your mash schedule, and try it without the low protein rest.

BTW oats and wheat don't necessarily cause haze.

Also BTW, using multiple and/or prolonged beta rests can help increase attenuation without needing to add enzyme. And also there are less powerful enzyme products you can use (regular amylase), but I'm not sure if those would be helpful.

Once again, thanks for the detailed answer. Little by little the science is beginning to filter in, but I fear I'm often conflating terms, products and processes. I need to sit down and spend time "coming to terms with 'terms'," before I can resolve my issues, define my goals and plot a course. Only then will I be prepared to learn by doing. You guys are giving me a graduate level course that I should have learned in my under graduate studies. Thanks for your patience.

Brooo Brother
 
I'd say you're on the right track.



A protein rest (your 113F rest) breaks down proteins. With modern, well modified malts, that has already been done and doing that rest in your mash probably reduces body. Stuck lauter/recirc can be avoided by adding rice hulls.

I agree, but according to Fix a brief rest at 113F (bottom of the 113F-131F 'protein rest') does not adversely affect body. Palmer writes:

"Before the turn of the (last) century, when the interaction of malt and water chemistry was not well understood, brewers in Pilsen used the temperature range of 86-126°F to help the enzyme phytase acidify their mash when using only pale malts. The water in the area is so pure and devoid of minerals that the mash would not reach the proper pH range without this Acid Rest. Most other brewing areas of the world did not have this problem.

Pale lager malt is rich in phytin, an organic phosphate containing calcium and magnesium. Phytase breaks down phytin into insoluble calcium and magnesium phosphates and phytic acid. The process lowers the pH by removing the ion buffers and producing this weak acid. The acid rest is not used nowadays because it can take several hours for this enzyme to lower the mash pH to the desired 5.0 - 5.5 range. Today, through knowledge of water chemistry and appropriate mineral additions, proper mash pH ranges can be achieved from the outset without needing an acid rest."

I think that's the "acid rest" and "modification" most of us are thinking about when referring to "protein rest" (protease enzyme). According to Palmer, protease is active 113F-131F, but Fix suggests that below 120F in that range that a brief rest isn't problematic to proteins. Note that Pilsen brewers conducted hours' long acid rests. What I'm trying to do with a :15 minute rest is neither acidification nor 'significant' protease reduction, but rather capture other processes that also occur at 113F. Specifically they are solubilization of starches, breaking down gums, and production of FANS. All those things happen in a mash temperature range that includes 113F.

So I'm not trying to do a protein rest or lower pH through an acid rest since modern malts don't usually benefit from it. It's those other under-appreciated enzymes that I'm hoping to use to improve the mash. If the pH drops a little or if a few proteins get reduced without affecting body, then that's just a bonus. And thanks for the reminder of rice hulls. I did a 50% wheat/50% barley beer last summer and still have some rice hulls left over from that mash. I just included them in my recipe along with flaked oats.

Brooo Brother
 
Specifically they are solubilization of starches, breaking down gums, and production of FANS. All those things happen in a mash temperature range that includes 113F.
* "Solubilization of starches" is called gelatinization, and it doesn't occur to a significant extent at a temperature that low.
* Breaking down of gums (beta glucans) is definitely not needed.
* Additional FAN is not needed. Wort has lots of YAN regardless, and combined with a healthy pitch rate and reasonable fermentation practices, there's no need for an additional nitrogen-liberating step.

Hope this helps.

Again, based on a lot of data from people intimately familiar with step mashing, I'd suggest starting no lower than 130-131°F. ... Which you'll notice is in the range you quoted, but this higher temperature is less likely to negatively affect the medium-length proteins that affect body and head.
 
What I'm trying to do with a :15 minute rest is neither acidification nor 'significant' protease reduction, but rather capture other processes that also occur at 113F. Specifically they are solubilization of starches, breaking down gums, and production of FANS.

solubilization of starches: happens at Saccharification rest temps
breaking down gums: do you mean beta glucans? Not necessary with well modified malts
production of FANS: Not necessary with well modified malts

I think you are overthinking this, i.e. you have a solution in search of a problem.

BTW, Acid rests and Protein rests are different. The temp ranges happen to overlap. Neither is necessary with well modified malts. And when we say "well modified malts" we're talking about the malting process.
 
I can see I have some misconceptions I have to square with reality.

Ya know, I respect John Palmer, but I really wish he had never even mentioned acid and protein rests in "How to Brew." Acid rests are a historical curiosity. And protein rests have very limited application. Most brewers could brew a lifetime of brews without needing to do one.
 
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