Has anyone tried caramelizing lactose?

[helibrewer]

Carmelization is a hydrolysis reaction. For Table sugar (surcrose) it breaksdown into glucose and fructose. For Lactose (another dissacharide) it breaksdown into glucose and galactose.

Yeast will not ferment galactose in the presence of glucose and I have seen some literature that suggests that with glucose present the yeasts gene for fermenting galactose never gets turned on so even once all the glucose is consumed, the galactose will not be fermented providing residual sweetness.

 

[ColumbusAmongus]

Carmelization is a hydrolysis reaction. For Table sugar (surcrose) it breaksdown into glucose and fructose. For Lactose (another dissacharide) it breaksdown into glucose and galactose.

Yeast will not ferment galactose in the presence of glucose and I have seen some literature that suggests that with glucose present the yeasts gene for fermenting galactose never gets turned on so even once all the glucose is consumed, the galactose will not be fermented providing residual sweetness.

Ah...not even close. Hydrolysis is specifically the addition of water to cleave a bond. Polysaccharides do hydrolyze in presence of heat and water but much more happens after that in caramelization. You end up with all sorts of crazy high molecular weight species, not just a pot of monosaccharides.

 

[bottlebomber]

Carmelization is a hydrolysis reaction. For Table sugar (surcrose) it breaksdown into glucose and fructose. For Lactose (another dissacharide) it breaksdown into glucose and galactose.

Yeast will not ferment galactose in the presence of glucose and I have seen some literature that suggests that with glucose present the yeasts gene for fermenting galactose never gets turned on so even once all the glucose is consumed, the galactose will not be fermented providing residual sweetness.

Interesting. What is your source for this if you don't mind? It seems like your saying that caramelized lactose is at least partially fermentable, while lactose itself is not. Is that right?

Edit: Oh, and are you a member of the Beerocrats?

 

[emjay]

Ah...not even close. Hydrolysis is specifically the addition of water to cleave a bond. Polysaccharides do hydrolyze in presence of heat and water but much more happens after that in caramelization. You end up with all sorts of crazy high molecular weight species, not just a pot of monosaccharides.

This. It should be rather obvious with even just a momentary glance that caramelized table sugar is more than simply glucose and fructose. It results in all kinds of different higher-order sugars, which should not be fermentable, especially since we actually know exactly which sugars these yeast species can ferment.

 

[ColumbusAmongus]

I'm still like 98% certain that this is actually untrue.

It is not true. Like I said, caramelization results in high molecular weight species that aren't even classified as sugars at that point.

 

[ColumbusAmongus]

This. It should be rather obvious with even just a momentary glance that caramelized table sugar is more than simply glucose and fructose. It results in all kinds of different higher-order sugars, which should not be fermentable, especially since we actually know exactly which sugars these yeast species can ferment.

Exactly. Monosaccharides aren't brown either.

 

[bottlebomber]

Emjay, let me know if you can find any flaws in this - I'm going to weigh out around 50 grams of table sugar x2. One is going to be caramelized. The other is simply going to be dissolved. Both will be equal in volume (after redissolving in the case of the caramelized sugar). Now there's two things in curious about. If both are weighed accurately, and both have the same volume at 70 degrees, will the hydrometer read the same on both. And more importantly, how will they ferment comparatively. I will split a packet of yeast by volume between the two.

My theory is that they will be equally fermentable. However I have a funny thought that they may read differently on the SG. You suggested, if I'm not wrong, that the caramelized sugar would be highly unfermentable. I think you may be wrong, because a Bochet is probably similar in composition and it is fermentable.

 

[ColumbusAmongus]

Emjay, let me know if you can find any flaws in this - I'm going to weigh out around 50 grams of table sugar x2. One is going to be caramelized. The other is simply going to be dissolved. Both will be equal in volume (after redissolving in the case of the caramelized sugar). Now there's two things in curious about. If both are weighed accurately, and both have the same volume at 70 degrees, will the hydrometer read the same on both. And more importantly, how will they ferment comparatively. I will split a packet of yeast by volume between the two.

My theory is that they will be equally fermentable. However I have a funny thought that they may read differently on the SG. You suggested, if I'm not wrong, that the caramelized sugar would be highly unfermentable. I think you may be wrong, because a Bochet is probably similar in composition and it is fermentable.

No, he is right. Yeast will not ferment the polymeric hodge-podge of junk that is part of the caramel. Your test should result in a darker solution and a lighter solution. The darker solution will indicate the presence of unfermented caramelized junk.

I think you still have a lot of fermentable sugar left in a caramel so you might not see too huge of a difference.

 

[bottlebomber]

I think you still have a lot of fermentable sugar left in a caramel so you might not see too huge of a difference.

Thats kind of what I was thinking. There may be a difference, but not a large one. However, I was thinking that some of the caramelized solution may not even be fully soluble, and will not contribute to the reading. We shall see.

 

[Bierliebhaber]

I've made dulce de leche with sweetened condensed milk...I wonder if it would be soluble without curdling. I suppose adding a bit to 1-2 oz of RIS would answer that.

 

[helibrewer]

Exactly. Monosaccharides aren't brown either.

Monosacch will absolutely carmelize (brown) and at relatively low temps (160C for Glucose).

I wasn't trying to suggest that those were the only end product and there are 12 steps in carmelization each leaving a different set of end products. If you go all the way to Black Jack (step 12) you have nothing left that is fermentable and plenty of diacetyl, furones and furans.

Caramel malt has carmelized sugars and they do contribute to fermentability, just not to a great extent.

 

[ColumbusAmongus]

Thats kind of what I was thinking. There may be a difference, but not a large one. However, I was thinking that some of the caramelized solution may not even be fully soluble, and will not contribute to the reading. We shall see.

It probably is with a light caramelization but I am not so sure a hydrometer is the best "instrument" since it only measures density. The solubilized caramel component will prob contribute to the OG so I wouldn't expect a diff there and then the FG diff will prob be too small to measure on a hydrometer.

If he wants to be dorky, he could measure the volume of CO2 kicked off but even then...the difference is prob smaller than the error of a home experiment.

 

[emjay]

If both are weighed accurately, and both have the same volume at 70 degrees, will the hydrometer read the same on both.

Not necessarily, even if it remains all in solution, as the density of the molecules produced can differ. If they're different, you might even try having a third solution, using caramel to the same SG as the table sugar solution. I suspect the difference might be smaller than you're capable of reliably measuring, though.

You suggested, if I'm not wrong, that the caramelized sugar would be highly unfermentable. I think you may be wrong, because a Bochet is probably similar in composition and it is fermentable.

Here's the thing... even I will admit that caramel isn't necessarily "highly unfermentable", for two reasons. The first is that the term itself is subjective... at what point does it go from somewhat unfermentable to "highly" so?

But more importantly, and on a somewhat related note, caramelization is a process that can be done to different degrees, it's not like there's a sharp division between uncaramelized and caramelized sugar. So what I'm saying is that fermentability will be affected by the degree to which you caramelize the sugars. If you only lightly caramelize them, it will be more fermentable than a well-caramelized solution. And in practice, I'd say it's always going to be fermentable, if only partially so.

We know that all these higher order sugars and other crazy molecules are created during the caramelization process, and we know that the yeast we use only has the enzymes to ferment a handful of simpler sugars. I'm not sure where in the science you think there's room for the possibility that it will remain 100% fermentable, because it should be clear that there isn't.

That's not to say that caramelizing lactose is pointless, as it will certainly produce a different product, but the assumption that led you to think it necessary is indeed incorrect.

Feel free to do the experiment anyways, as there's little harm in doing it. Unless you conduct it poorly, that is, so just make sure the sugar is VERY well-caramelized so that it isn't merely slightly unfermentable with the difference in FG falling within the margin of error. Use a specialized FG hydrometer if you can to reduce this margin of error. But really, if the initially brown solution doesn't turn clear, there isn't even really any need to take the measurement, is there?

Anyways, I don't mean to sound like a pompous ******* or dismissive of your idea "just because", and I hope you understand that. But the science behind all this is well understood and there's really no scientific basis whatsoever for your hypothesis.

 

[bottlebomber]

Not necessarily, even if it remains all in solution, as the density of the molecules produced can differ. If they're different, you might even try having a third solution, using caramel to the same SG as the table sugar solution. I suspect the difference might be smaller than you're capable of reliably measuring, though.

Here's the thing... even I will admit that caramel isn't necessarily "highly unfermentable", for two reasons. The first is that the term itself is subjective... at what point does it go from somewhat unfermentable to "highly" so?

But more importantly, and on a somewhat related note, caramelization is a process that can be done to different degrees, it's not like there's a sharp division between uncaramelized and caramelized sugar. So what I'm saying is that fermentability will be affected by the degree to which you caramelize the sugars. If you only lightly caramelize them, it will be more fermentable than a well-caramelized solution. And in practice, I'd say it's always going to be fermentable, if only partially so.

We know that all these higher order sugars and other crazy molecules are created during the caramelization process, and we know that the yeast we use only has the enzymes to ferment a handful of simpler sugars. I'm not sure where in the science you think there's room for the possibility that it will remain 100% fermentable, because it should be clear that there isn't.

That's not to say that caramelizing lactose is pointless, as it will certainly produce a different product, but the assumption that led you to think it necessary is indeed incorrect.

Feel free to do the experiment anyways, as there's little harm in doing it. Unless you conduct it poorly, that is, so just make sure the sugar is VERY well-caramelized so that it isn't merely slightly unfermentable with the difference in FG falling within the margin of error. Use a specialized FG hydrometer if you can to reduce this margin of error. But really, if the initially brown solution doesn't turn clear, there isn't even really any need to take the measurement, is there?

Anyways, I don't mean to sound like a pompous ******* or dismissive of your idea "just because", and I hope you understand that. But the science behind all this is well understood and there's really no scientific basis whatsoever for your hypothesis.

I'm getting two messages here - one concerning what we are currently discussing (which I guess is technically OT), the matter of whether or not caramelized table sugar is significantly less fermentable than sugar which has not been caramelized. I think the difference will be negligible, and in fact the experiment is already underway, sans permission. My scale is only accurate to a gram, so I will take the advice and make the solutions uniform on my Brix refractometer. I'll also double check them on the hydro. I will retract my statement that the caramelized version is 100% fermentable, in lieu of this - it is not significantly less fermentable. I am confident of this to the extent that I feel comfortable monitoring the experiment with the equipment I have.

The second matter being your assertion that caramelized lactose may not be useful as a brewing practice. I don't know if it is, which is why, after being unable to locate any information on it, I started the process (and the thread). As far as I'm aware of you haven't tried it, and you don't know anyone else who has, so to denounce the practice would make you categorically a little pompous, yes. I am at least willing to give it a shot. Now, if I make one beer with it, one which I designed the recipe for and have never made, and my conclusion is "it's good!", that is hardly scientific. It is something I want to keep playing with. Just like everything else I do, I will decide for myself whether it is worthy, and share the results.

 

[emjay]

The second matter being your assertion that caramelized lactose may not be useful as a brewing practice.

Huh? I didn't say that. In fact, I said the opposite. :/

That's not to say that caramelizing lactose is pointless, as it will certainly produce a different product

The thing I have been disagreeing with was your initial assertion (and then later reassertion) that caramelizing sucrose for beer was an exercise in futility as it would just be completely fermented anyways, which simply isn't true.

 

[bottlebomber]

Huh? I didn't say that. In fact, I said the opposite. :/

My apologies for the misunderstanding. See, I've been spending too much time with you in the debate forum. If I had been spending more time in the Tap Room, I could just call you a bitch and be done with it

The thing I have been disagreeing with was your initial assertion (and then later reassertion) that caramelizing sucrose for beer was an exercise in futility as it would just be completely fermented anyways, which simply isn't true.

Aaah, gotcha. It's been a long week. Well, the good news is that said fermentation is underway. I deeply caramelized 50 grams of sugar until it was smoking. Even with my primitive equipment, both samples came out to exactly 1.028 on my refractometer, and 1.030 on the hydro. I wish I would have made it higher gravity to get a broader spectrum, and it might not be adequate. If no obvious difference is measurable, I may try it again with 150 grams.

The difference to me though, is that for my application I would not use simple sugar, because it is a stout. I wanted the caramel to be fully non-fermentable, not just partially.

 

[emjay]

You should do a third and fourth solution with caramelized and straight lactose, at the same gravity. The galactose could indeed make the former partially fermentable.

 

[bottlebomber]

You should do a third and fourth solution with caramelized and straight lactose, at the same gravity. The galactose could indeed make the former partially fermentable.

I think I will! That was definitely an interesting idea. Even though Heli never really followed up with any source material he seemed to know what he was talking about, and that's grounds for an experiment. I know from what I did that the flavor was very different. I've never heard of galactose.

 

[emjay]

I think I will! That was definitely an interesting idea. Even though Heli never really followed up with any source material he seemed to know what he was talking about, and that's grounds for an experiment. I know from what I did that the flavor was very different. I've never heard of galactose.

Just like the disaccharide sucrose is made up of the monosaccharides glucose and fructose, lactose is the same, except there is a galactose instead of a fructose. I know brewers yeast is capable of fermenting galactose, and I would expect lactose to "invert" like sucrose does when heated, so it would make sense.

However, he grossly oversimplified and even straight up mischaracterized the caramelization process. In fact, what he described pretty much IS the "inversion" process (ie hydrolysis).

 

[bottlebomber]

Results are in.

Lol.

Both samples have dropped clear for a good day now. The gravity of the straight sugar went from 1.028 down to .998. The caramelized version started at 1.028, and when fermentation was complete it came down to... Wait for it...

1.020. Maybe 1.018.

So I can definitely conclude(read concede) that caramelized table sugar is SIGNIFICANTLY less fermentable. I am actually really glad I did this, because I had planned on priming the beer with caramelized sugar, and now I know to not do this. The degree of fermentability is far to unpredictable. Cool experiment.

 

[bottlebomber]

The other thing I learned that I was wondering about, is that I've heard it mentioned that table sugar must be boiled to ferment properly. Bollocks.

 

[emjay]

Results are in.

Lol.

Both samples have dropped clear for a good day now. The gravity of the straight sugar went from 1.028 down to .998. The caramelized version started at 1.028, and when fermentation was complete it came down to... Wait for it...

1.020. Maybe 1.018.

So I can definitely conclude(read concede) that caramelized table sugar is SIGNIFICANTLY less fermentable. I am actually really glad I did this, because I had planned on priming the beer with caramelized sugar, and now I know to not do this. The degree of fermentability is far to unpredictable. Cool experiment.

Definitely cool. About the fermentability I had expected from moderate-to-well caramelized sucrose. Just under 19% attenuation.

You should now do the same with 1.028 lactose solutions, making sure that the caramelized lactose is at least as well-caramelized as the sucrose was.

The other thing I learned that I was wondering about, is that I've heard it mentioned that table sugar must be boiled to ferment properly. Bollocks.

It's technically easier. I suppose it might even be true for some mutant strains.

Yeast is not typically able to ferment sucrose directly. It must enzymatically cleave it into glucose and fructose, and then ferments those monosaccharides. Boiling it first (especially, but not necessarily, with some sort of acid) helps "invert" it (ie it creates what's called "invert sugar") which is essentially the same thing - splitting the disaccharide sucrose into glucose and fructose.

So the claim might have SOME basis in reality, though it's pretty safe to assume you don't need to. But boiling sucrose before adding it is always a good practice (from a sanitation standpoint), and it IS technically easier for the yeast to ferment the invert sugar.

Now that I think of it, it may even be possible for boiled sugar to allow a bottle to carb more quickly than sucrose. I actually doubt the difference would be noticeable - and I certainly don't think the sucrose would make it lag even a single day behind - but it could be an interesting experiment

 

[emjay]

Also, you can still use it for priming. You have to make a large amount, well-mixed. Then you'd have to test the batch's fermentability like you did here.

To find the required mass of the caramelized sucrose needed, just multiply the mass of sucrose you need (Ms) by the fermentability of sucrose (Fs = 100%), divided by the real attenuation of the caramelized sample (Fc).

The following describes the equality of mass times fermentability:
Mc * Fc = Ms * Fs

And you can figure out what you need by rearranging it to what I described in words in the second paragraph.
Mc = Ms * Fs / Fc

In this case:
Mc = Ms * 100 / 18.77
Mc = Ms * 5.33

In other words, you'd take the mass of sucrose you would use to get the carbonation you want, and multiply it by 5.33 to get the mass of the caramelized sugar you'd need. If there's water involved, then you would need to calculate the volume of priming solution needed, and the SG of it. Then you either make a caramel solution that has the same SG, but use 5.33 times the volume, or one that has the same volume, but 5.33 times the gravity points.

Hopefully I didn't make it sound too complicated, because it's not. This would be a great way to maximize the caramel flavor without thinning out the beer (or increasing ABV) more than you would have with a standard priming solution anyways, and it would be a shame to miss out on that just because it involves a bit of math. If it seems too complicated, I'd be happy to do the math if you could give me the OG and FG of the fermentability test for the particular batch of caramel you intend to use.

 

[bottlebomber]

The equation seems solid. I would definitely want to repeat the experiment at least once more before I stake an expensive batch of beer on it. If I could do it two more times and get very similar results I'd feel comfortable carbing a batch this way. Even a difference of 10% attenuation would make me feel a little leery though. As you mentioned before, there's a broad range in caramelization.

 

[emjay]

The equation seems solid. I would definitely want to repeat the experiment at least once more before I stake an expensive batch of beer on it. If I could do it two more times and get very similar results I'd feel comfortable carbing a batch this way. Even a difference of 10% attenuation would make me feel a little leery though. As you mentioned before, there's a broad range in caramelization.

Yeah, that's why I said you'd have to test the attenuation of the same batch of caramelized sugar that you plan on using to prime.

 

[bottlebomber]

Gotcha

 

[keesh]

I'd just like to add that this thread has progressed quite nicely and I am very happy to have see your results, bottlebomber. Also, the discourse is excellent.

 

[bottlebomber]

I'd just like to add that this thread has progressed quite nicely and I am very happy to have see your results, bottlebomber. Also, the discourse is excellent.

Thanks! I've still got 2 more experiments to do with the lactose now, but I'd like to use the thread to document other things I do with the caramelizing efforts, until I hone some good applications or decide it isn't worth the effort.

 

[seabass07]

Old thread bump.

Any chance your final beer ended up with some caramelized milk flavors? I'm curious about what kind of flavors you got with the caramelized lactose in the final beer.

 

[bottlebomber]

Old thread bump.

Any chance your final beer ended up with some caramelized milk flavors? I'm curious about what kind of flavors you got with the caramelized lactose in the final beer.

Yes, absolutely they did. I am going to experiment with this process again soon to see how much lactose I can get away with using before I get an overly heavy beer. I used 12 oz for the creme brûlée stout, and the FG was 1.025 but not even close to being overly sweet. I think depending on the recipe you could use 1-1.5 lbs. the FG will be quite high, but it doesn't taste sweet. I'm going to try this method in a caramel amber ale to see what I'm dealing with. The flavor came through in the stout but the recipe I developed had a terrific amount of roasted grain.