Loss of Diastatic Power from Toasting Malt

[TheMadKing]

Ok some actual data:

This malt is no longer diastatic. A mini mash of .5 hours fine grind resulted in a positive iodine test.

The color is much less than you reported @dmtaylor in your batch despite double the time in the oven.

The mash pH is 5.2 using my filtered home water (not DI. residual alkalinity is 24ppm)

The mini mash smells like medium dark toast, and tastes like dry toast with almost no sweetness or Caramel flavors at all

So I'm chalking this up to the water soak before I started. I think I will prefer the results with toasting dry malt

 

[Miraculix]

The grain picked up a nice biscuit/light toast flavor at 40 minutes but the moisture content is still quite high.

It tastes great but I'm worried about its shelf stability with the moisture this high. It's still cooling so I hope it continues to dry

The flavor is best compared to melanoidin I think

You've been basically mashing partially the grains while baking. The enzymes defolded and therefore became vulnerable to temperature. My guess is that there is now no diastatic power left because of the water.

Edit: parallel post

 

[TheMadKing]

You've been basically mashing partially the grains while baking. The enzymes defolded and therefore became vulnerable to temperature. My guess is that there is now no diastatic power left because of the water.

Edit: parallel post

Yep agreed, I'm doing a second batch right now with no water

 

[TheMadKing]

Ok one more to report back:

3lb american 2-row toasted at 300F for 55 minutes

smells like dark bread crust, or almond roca (no not like almonds, just very nutty with a hint of chocolate)

The mini mash sat for 30 minutes and still resulted in a positive iodine test indicating that this malt is also no longer diastatic. I can taste a hint of sweetness though, so perhaps there is still a small amount of enzymes left. The color is medium brown, I'd estimate the liquid color to be about 15 SRM. It tastes toasty and bready, and just hint of roast.

I would definitely call the resulting malt "brown" but unfortunately I have denatured the majority of the enzymes. I think @dmtaylor you managed to strike the right balance on your first shot, and you may have toasted a bit lighter than I'm going for too. I'm overall happy with the resulting malt, and I think it will make a nice addition to my scottish ale, but it's not suitable for a SMASH beer any time soon.

In keeping with @bracconiere s post earlier, I will try a low and slow method too where I roast it at 185F for several hours and see what that gets me too

 

[dmtaylor]

The mini mash sat for 30 minutes and still resulted in a positive iodine test indicating that this malt is also no longer diastatic. I can taste a hint of sweetness though, so perhaps there is still a small amount of enzymes left. The color is medium brown, I'd estimate the liquid color to be about 15 SRM. It tastes toasty and bready, and just hint of roast.

In keeping with @bracconiere s post earlier, I will try a low and slow method too where I roast it at 185F for several hours and see what that gets me too

Great experiment, thanks for sharing.

I wonder if 30 minutes wasn't long enough to run an iodine test. I had conversion happening within a few minutes, but I didn't do any iodine tests. If I were expecting an iodine test to come out clean, I would have waited at least 75-90 minutes for that. I mean, I know when I am using Munich malt for the main base malt, I need to extend my normal mash time of 45 minutes to at least 60-90 minutes because there is in fact lower diastatic power in these darker base malts. If I ran an iodine test at 30 minutes, I would absolutely expect a positive result. What I'm saying is...... you might still have enzymes in there... AND I think an iodine test is of very low value, unless I was running a mash of say 2-3 hours when I might expect it to come out totally negative. Any time before that.... not so much. The 75-90 minute point might be the point of being "good enough" for decent efficiency and fermentability, regardless of iodine test.

I do think a very loooong roast at 185 F should give interesting results. But just might take 3, 4, 5 hours at that temperature to get much impact.

 

[dmtaylor]

And all that being said......

I fear my attenuation is going to suck. Currently fermentation is slowing way down. My Tilt right now is saying 1.029 on the batch fermented with Diamond (started at 1.053). I sure hope it keeps on chugging for a while longer as I would like it to go under 1.020. But at this point, I am beginning to have doubts that it will happen. So I fear I did not mash long enough. Sure, starches were breaking down into complex sugars and dextrins, but.... much of these cannot be fermented by beer yeast. Dagnabbit. I hope my fears are untrue. But I'm often correct about such things. Time will tell.

 

[Silver_Is_Money]

I'm doing my first test today. As a baseline I'm following the advice of Randy Mosher and I soaked the malt for a few minutes, and I'm baking for 40 minutes at 375.

So far so good and it smells great

Soaking the malt before roasting it may put you on the path to producing a caramel/crystal type malt.

 

[bracconiere]

I will try a low and slow method too where I roast it at 185F for several hours and see what that gets me too

i usually leave it at 170f overnight, the oven auto shuts off after 12 hours.....but my oven creeps up to 200f maybe a couple degrees hotter. so i'd recommend starting at 170f, wait 2-3 hours, shoot an IR temp gun at the grain. and adjust from actual temp...


my understanding is that 200f kilning makes basically dark munich...and i've used it for 4 years before that post, and know it has plenty diastatic power...


i'd describe the taste, to the best of my ability, decievingly light, and carmel nutty, for how dark it is....

you're using already kilned malt though, so YMMV...

 

[TheMadKing]

Soaking the malt before roasting it may put you on the path to producing a caramel/crystal type malt.

I thought the same thing, but then he specifies a process for creating crystal malt which requires soaking for 24 hours.

I think moisture can be used without creating crystal malt, but I only soaked for 5 minutes and it was too much. I think a light spritz of water, or even a bowl of water in the oven to increase the humidity might yield better results

 

[TheMadKing]

Now I fully understand why there are recommendations to rest your malt for a couple weeks

I stashed those (and a third batch of toasted pils. 30 min at 400F, still not able to self convert, but very nice smelling) in paper bags in a closet and shut the door.

30 hours later I opened the door to look for something and the whole closet is absolutely OVERPOWERING with the smell of the malt. It smells very similar to overheated popcorn and isn't entirely pleasant, so I think that'll be those volatiles coming out.

 

[Silver_Is_Money]

I still think its best to hold the temperature at (or below) 250 degrees F., and vary the oven time, rather than trying to hurry things along by bumping temperatures into the 350-400 degree F. range.

One major caveat: Conventional cooking ovens are notoriously terrible at holding temperature at or near the desired set point temperature. This alone makes it difficult to equate one persons malt toasting experience with another's.

 

[Miraculix]

I still think its best to hold the temperature at (or below) 250 degrees F., and vary the oven time, rather than trying to hurry things along by bumping temperatures into the 350-400 degree F. range.

One major caveat: Conventional cooking ovens are notoriously terrible at holding temperature at or near the desired set point temperature. This alone makes it difficult to equate one persons malt toasting experience with another's.

You'd actually need to keep a thermometer inside all time to be able to reliable tell the ongoing temperature.

 

[dmtaylor]

My fermentation appears to be stalled at 1.027, that's 50% attenuation from OG 1.053. Dagnabbit. I'll have to think about how best to resolve. I really don't like the idea of adding some type of enzymes, but now I have to give it more serious thought. Temperature has been stable at 64-65 F so that's not the issue. I just didn't mash long enough for the very low amount of enzymes that were in there.... enough to convert starch to dextrin, but not enough to convert dextrin to simple sugar. I'm disappointed.

 

[TheMadKing]

My fermentation appears to be stalled at 1.027, that's 50% attenuation from OG 1.053. Dagnabbit. I'll have to think about how best to resolve. I really don't like the idea of adding some type of enzymes, but now I have to give it more serious thought. Temperature has been stable at 64-65 F so that's not the issue. I just didn't mash long enough for the very low amount of enzymes that were in there.... enough to convert starch to dextrin, but not enough to convert dextrin to simple sugar. I'm disappointed.

A tiny amount of glucoamylase will get it moving again. You'll need to cold crash and keg it when it hits the FG you want though because otherwise it'll ferment totally to 1.000

 

[TheMadKing]

I want to resurrect this thread once more and report back.

The Scottish Ale competition was a couple weeks ago and I'm sorry to report I didn't win. I took 2nd place out of 10 entries with a score of 38.

I ended up using 1lb of the toasted pils malt in a more conventional grain bill and I think it was too much. The resulting beer was very heavy in the mid-range melanoidin flavors and had my and Miraculix's dreaded marzipan flavor. I also suspect that my addition of 2lb of simple sugar caused a more estery beer which is the root of that marzipan flavor.

Overall it was a good beer, and i think my home toasted malt was a successful specialty grain, but i have not yet achieved a self converting brown malt.

I'll give it a few more shots though!

 

[Miraculix]

I want to resurrect this thread once more and report back.

The Scottish Ale competition was a couple weeks ago and I'm sorry to report I didn't win. I took 2nd place out of 10 entries with a score of 38.

I ended up using 1lb of the toasted pils malt in a more conventional grain bill and I think it was too much. The resulting beer was very heavy in the mid-range melanoidin flavors and had my and Miraculix's dreaded marzipan flavor. I also suspect that my addition of 2lb of simple sugar caused a more estery beer which is the root of that marzipan flavor.

Overall it was a good beer, and i think my home toasted malt was a successful specialty grain, but i have not yet achieved a self converting brown malt.

I'll give it a few more shots though!

The mazipan still is a big mystery to me... I've managed to lower it, but sometimes it still shows up. The last batch I've tasted it included invert sugar..... Hmmmmm....... You might be on to something with your ester theory.

At least I'm not alone with it.

 

[Miraculix]

How are you heating your mash when doing stepped mashes? You do stepped mashes, don't you?

 

[Misplaced_Canuck]

The mazipan still is a big mystery to me... I've managed to lower it, but sometimes it still shows up. The last batch I've tasted it included invert sugar..... Hmmmmm....... You might be on to something with your ester theory.

At least I'm not alone with it.

Very late to the game on this one... What percentage of home-toasted malt are you using?

 

[Miraculix]

Very late to the game on this one... What percentage of home-toasted malt are you using?

None, i think you might have addressed the wrong person.

 

[Misplaced_Canuck]

None, i think you might have addressed the wrong person.

Yeah, I was addressing to MadKing...

 

[AlexKay]

Sugar Creek has a London Brown diastatic malt on their website. It's been listed as "coming soon" for a while. I dropped them a line to figure out when soon might be.

 

[Dland]

My fermentation appears to be stalled at 1.027, that's 50% attenuation from OG 1.053. Dagnabbit. I'll have to think about how best to resolve. I really don't like the idea of adding some type of enzymes, but now I have to give it more serious thought. Temperature has been stable at 64-65 F so that's not the issue. I just didn't mash long enough for the very low amount of enzymes that were in there.... enough to convert starch to dextrin, but not enough to convert dextrin to simple sugar. I'm disappointed.

Just wondering, is it possible the toasting rendered some of the sugars less or unfermentable?

I'm actually not clear on this, has been my understanding that malts like dark crystal add unfermentables. Was not aware that longer mash (with enzyme activity) would make un fermentable sugars fermentable, but I guess maybe the betas do this if strong enough.

 

[dmtaylor]

Just wondering, is it possible the toasting rendered some of the sugars less or unfermentable?

I'm actually not clear on this, has been my understanding that malts like dark crystal add unfermentables. Was not aware that longer mash (with enzyme activity) would make un fermentable sugars fermentable, but I guess maybe the betas do this if strong enough.

Yes, you are onto something. Crystal malts add unfermentables because the enzymes are active for part of the caramelization process but then killed off. I do believe I experienced the same phenomenon in my own beer.

Even alpha will break down most of the less fermentable sugars into more fermentable sugars. Beta is helpful, but if the beta breaks down, alpha can do a lot as well, especially if given extra time (such as an overnight mash).

FWIW… my experimentally home-toasted beer ended up very tasty and well carbonated over time. I added like a half a Beano tablet to it, and the idea worked. Beano is definitely not a cure-all, but… in THIS case, it was helpful.

 

[TheMadKing]

How are you heating your mash when doing stepped mashes? You do stepped mashes, don't you?

I use an electric HERMS system, so I open my recirculation pump up full flow and set my HLT temperature to about 3-4 degrees above where I want the mash to settle and let the mash temp rise as fast as it can.

 

[TheMadKing]

Yeah, I was addressing to MadKing...

I used 10% in this recipe. I think dropping it down to 5-7% might be better

 

[Miraculix]

I use an electric HERMS system, so I open my recirculation pump up full flow and set my HLT temperature to about 3-4 degrees above where I want the mash to settle and let the mash temp rise as fast as it can.

OK, so you are not heating a biab setup via direct heat as I do... I thought maybe I am scorching the grain a little bit and create the marzipan flavour that way, but if you get it by just heating the liquid this is not a valid idea anymore.

 

[TheMadKing]

OK, so you are not heating a biab setup via direct heat as I do... I thought maybe I am scorching the grain a little bit and create the marzipan flavour that way, but if you get it by just heating the liquid this is not a valid idea anymore.

Yeah assuming we are describing the same flavor at all lol

My money is on ester content from sugars and english yeasts. I only notice it in malty English ales, never american ales or german lagers

 

[Miraculix]

Yeah assuming we are describing the same flavor at all lol

My money is on ester content from sugars and english yeasts. I only notice it in malty English ales, never american ales or german lagers

Interesting. I also do not have this problem when brewing mmmmurican pales. But I must say, I often use Nottingham for APAs, so that would be English, but low ester English.

I mean, I mainly brew bitters, but I also mainly witness these marzipan offs within bitters and a lot of them get some invert.

Maybe the esters are kind of a precursor for the marzipan and then later it only needs a hint of oyxygen to blossom? No idea tbh.... it looks like oxygen really plays a role.