Testing fermentability of crystal malt

[passedpawn]

One thing to be sure of - replication of your treatments. For this experiment to be more valid you should repeat your experiment several times (more the better). This way you will capture more of the variance in your procedure and things you can't (or aren't) controlling for.

Re-read original post.

 

[nilo]

Update on the results of the first test.
Basically, it shows that a good amount of sugars from a crystal malt is fermentable.
As I stated before, this is just the first set of data points of several more to come to give it some credibility.
One thing that actually surprised me was the detection of startches in wort of all three malts. I though that all starch were already coverted to sugars inside the grain, but that doesn't seems to be the case.
I think that I didn't get the max PPG from the grain. I will turn the grain into flour next time to make sure I get anything possible. I milled the grain 3 times on this first test.
Below is a table that shows the most important parameters tested and results. Also attached the fermentation profiles and pic of the iodine tests of crystal 10L.

 

[passedpawn]

Woah, that's crazy. Incomplete starch conversion, and fermentable. Great info. I'm latching this into my database upstairs. Thanks. If you have the time and desire to repeat, that would be excellent

 

[Bigscience]

Did you do the starch test on a paper towel?

Also, how did you take the gravity readings?

 

[nilo]

Did you do the starch test on a paper towel?

Also, how did you take the gravity readings?

=>Yes

=>Daily with a refractometer.

 

[motobrewer]

all 3 approached 1.010 and stopped?

 

[nilo]

all 3 approached 1.010 and stopped?

That is correct

 

[Kaiser]

Nice job Nilo, I have been pointed to this thread and subscribed to it.

Have you also tested the FG with a hydrometer, there has been some discussion over on the AHA board that lead to the conclusion that the commonly used Brix to FG conversion is not necessarily accurate. You don't have to do that every day but it would be nice to see the last FG to be read with both the refractometer and the hydrometer.

If you want to simplify the testing you may also test the gravity only once after all signs of fermentation have ceased. That's what I did when I ran fermentability experiments like yours.

Cheers,
Kai

 

[motobrewer]

That is correct

hm, was this expected? any thoughts?

i would have thought FG's would have been different for each malt.

 

[nilo]

Nice job Nilo, I have been pointed to this thread and subscribed to it.

Have you also tested the FG with a hydrometer, there has been some discussion over on the AHA board that lead to the conclusion that the commonly used Brix to FG conversion is not necessarily accurate. You don't have to do that every day but it would be nice to see the last FG to be read with both the refractometer and the hydrometer.

If you want to simplify the testing you may also test the gravity only once after all signs of fermentation have ceased. That's what I did when I ran fermentability experiments like yours.

Cheers,
Kai

Thanks for the imput Kai.
Gravity was only taken with a refractometer, using a long formula to covert from brix.
I have tested the formula results before with other batches against a hydrometer and it proved very accurate.
But I can use both refractometer and hydrometer for OG and FG's for future tests, just to be on the safe side.

 

[BrewMoreBeers]

subscribed.

 

[Bigscience]

Did you do the starch test on a paper towel?

Also, how did you take the gravity readings?

=>Yes

=>Daily with a refractometer.

Well I'll be damned. I was going to say that you got a false positive due to the paper towel but I just tried it out and it worked out great. I never would have guessed that. I don't even use a waxed paper plate when test. I guess you learn somthing new every day.

 

[nilo]

Just finished brewing the second test batches, and have good news.
PPG were exactly the same than before for all 3 crystal malts(C10=20, C40=16, C120=16), confirmed also with a hydrometer. Looking good. Will report back once fermentation is completed.

 

[motobrewer]

interesting. i'm still confused as to why they all stopped at 1.01. i mean, that seems pretty random....

i figured they would all be x% fermentable.

 

[nilo]

interesting. i'm still confused as to why they all stopped at 1.01. i mean, that seems pretty random....

i figured they would all be x% fermentable.

The way I see it is that C10 is more fermentable than the other two and because the PPG is higher, all ended at same FG. The more roasted a malt, the less PPG and less fermentables. For crystal malt, there seems to be a threshold, which I'm not sure where it is (may be at 30 or 40L) after which the roasting level doesn't matter anymore and all will behave the same.
For other roasted malts (not crystals), it could be different. Like a 350L chocolate malt for example. I would expect no fermentables at all.
Once we get more data, we will hopefully see a clear pattern.

 

[theonetrueruss]

looking forward to the results.. I've been trying to find info on this myself... with no luck

 

[DeathBrewer]

Awesome experiment.

I recently learned from this forum that beta amylase can actually convert the long sugars (at some level) to shorter chains that become then fermentable, so I think that if you mash a crystal malt with another malt with diastatic power, it will affect the fermentability of the points coming from the crystal.

This has been my understanding, but I knew that you could get some fermentables from steeping as well but no idea how much. Glad to see the confirmation!

I hadn't thought about how the software calculated it...I'll definitely take that into consideration for future recipes! Can't wait to read more!

 

[GuldTuborg]

Great little experiment! I'll be watching this.

 

[BuzzCraft]

Nice job, nilo. Subscribed.

 

[nilo]

New update, test batch 2 is completed, and guess what?
Same results!
I did confirm with a hydrometer both OG's and FG's.
Here's a summary of results for both tests, fermentation profiles and a pic in case anyone wonders what a 1# of crystals looks like in 1 gal batch.
My next test will be 3 batches using only 2row malt, then a mix of 50% 2 row and 50% crystals.

 

[theonetrueruss]

Interesting that the FG is winding up at 1.01 so far regardless of the malt.. I wonder why that is? It seems unlikely that the different malts would jsut happen to have the exact right amount of fermentables to make it come out that way with different OGs.... I wonder if 2# of 120 was used in 1 gal if it would still make it down to 1.01?

 

[ajf]

Interesting that the FG is winding up at 1.01 so far regardless of the malt.. I wonder why that is? It seems unlikely that the different malts would jsut happen to have the exact right amount of fermentables to make it come out that way with different OGs.... I wonder if 2# of 120 was used in 1 gal if it would still make it down to 1.01?

Well, there's one sure fire way to find out.

Do it, and report back with the results.

I surely wouldn't expect nilo to do the experiment for you. I think he is doing quite enough to give us all a better understanding of what goes on during fermentation, and I applaud his efforts.

-a.

 

[theonetrueruss]

I just might... might be a good thing to try out over the xmas holiday. Planning a brew day over new years.. might do at the same time... 2 1 gallon with the same yeast in the same temp... 1 with 1#120 and 1 with 2#120 and see if there is a difference. hmm.. I'm gonna need to get another gallon jug. (only have 1 right now)

 

[BreckBastion]

Have you tasted the final product? Just curious. It would obviously seem very sweet with the lack of hops.

 

[wacko]

I wonder if you could make a crystal wine. Maybe shoot for 1.07 SG and end up with 1.035 and have a sweet beer at about 4%?

 

[wacko]

I guess the alc will be low for that style.

 

[nilo]

Have you tasted the final product? Just curious. It would obviously seem very sweet with the lack of hops.

It tastes nasty. I think it could be because the extraction of tanins during sparge as I washed the grain many times to get all possible sugars or because the yeast got stressed in processing the not so much fermentable sugars.

 

[Kaiser]

It tastes nasty. I think it could be because the extraction of tanins during sparge as I washed the grain many times to get all possible sugars or because the yeast got stressed in processing the not so much fermentable sugars.

Nilo, thanks for the update and thanks for sticking with this experiment. It’s the oddities in results that keep you thinking about refined experiments, isn’t it?

As for sparging, you don’t have to try to get all the sugar out of the grain. Doing a no-sparge, for example is sufficient. You can assess the grain potential based on the mash thickness and the gravity of the wort. That’s what maltsters do when they determine the extract potential.

The formula is

Extract potential = 100 * (Plato – R) / (100 – Plato)

Where Plato is the extract content of the wort in the mash and R is the mash thickness in l/kg. extract potential is then given in % of the malt’s weight. This cuts out the lauter efficiency.

Kai

 

[nilo]

Nilo, thanks for the update and thanks for sticking with this experiment. It’s the oddities in results that keep you thinking about refined experiments, isn’t it?

As for sparging, you don’t have to try to get all the sugar out of the grain. Doing a no-sparge, for example is sufficient. You can assess the grain potential based on the mash thickness and the gravity of the wort. That’s what maltsters do when they determine the extract potential.

The formula is

Extract potential = 100 * (Plato – R) / (100 – Plato)

Where Plato is the extract content of the wort in the mash and R is the mash thickness in l/kg. extract potential is then given in % of the malt’s weight. This cuts out the lauter efficiency.

Kai

Kai, the extract potential from this formula will still be affected by the milling process, right?
What I'm saying is that if you mill the grain coarse, mash and use this formula, the resulted extract potential will be less than if you mill it fine and redo the test.
What I was trying to do is to make the sugars as much soluble as possible by milling several times and to make my lautering efficiency close to 100% by washing it very well.
I thought it would give me the very max practical sugar extraction of a grain, which brewers would then apply their estimated mashing/lautering efficiency on top of that.
I'm not very convinced yet that I'm doing my best to extract the sugars. I may do a batch next using the grain turned into fine powder.
Thoughts?

 

[Kaiser]

Kai, the extract potential from this formula will still be affected by the milling process, right?

Yes, this extract potential is still affected by milling and mashing. If you put this potential in relation to the fine grid extract potential (after compensating for moisture content) you get the conversion efficiency.

What I'm saying is that if you mill the grain coarse, mash and use this formula, the resulted extract potential will be less than if you mill it fine and redo the test.

Yes.

What I was trying to do is to make the sugars as much soluble as possible by milling several times and to make my lautering efficiency close to 100% by washing it very well.

I see your point about getting the lauter efficiency to 100%. However, this is not needed if you determine conversion efficiency or extract achieved after mashing by using aforementioned formula. When I did my mashing experiments I wasn’t aware of this either and my process was to keep the lauter efficiency constant by using the same batch sparge method each time. If I would have known about conversion efficiency at the time I would have been able to get actual conversion efficiency numbers.

I'm not very convinced yet that I'm doing my best to extract the sugars. I may do a batch next using the grain turned into fine powder.

You can keep doing what you are doing. Just record the first wort or mash gravity at the end of mashing and the mash thickness at this point. The rest can be done when you analyze your results.

Kai