19 replies to this topic

[3rd party JKor]

I have a crapload of old grain left over from the last bulk buy I did when I was brewing a lot.  This is 4yo grain, I believe.  I had brewed a few batches with it early last year Jan/Feb. One of the beers, I felt, came out very good, one was meh.  It was with a completely new system, new water, new recipes, new everything, so i really couldn't say it was the grain or not, especially since one beer was very nice. 

 

Rather than throw out 100+ pounds of grain, I figured I should at least try to prove whether or not it's still fine of brewing (FYI, the raw grain flavor and texture, to me, is no different than 'fresh' grain).  So, I now have ingredients to brew two batches of session IPA, one with old grain one with new grain.  Not the best style for comparing grain, to be sure, but session IPA was next on the list.

 

I don't really have much attachment to the grain, I almost chucked it a few times already considering I didn't know when I'd ever use it, but didn't have a good place to throw it away.  I figure if it's useable, now, might as well use it.

[positiveContact]

My guess is it will make good beer.  I've used grain that old before.

[SchwanzBrewer]

If it tastes good, it feels fresh, hasn't absorbed much moisture, doesn't have bugs in it, and doesn't have mold on it then it's probably fine to use.

[3rd party JKor]

Yeah, that has always been my feeling as well.  It's always been stored in a cool place in plastic bins.  It's more of a curiosity to do the experiment.  Experiments are fun!

[denny]

My guess is it will make good beer.  I've used grain that old before.

 

Yep.

[3rd party JKor]

I ran this experiment on Saturday.  Two beers with the same grain bill (roughly) using new and old malts.  The grain bill was 2# of pale, 2# of Vienna and 0.25# of C15.  Mashed at 153.

 

Two big differences have been seen thus far.  The new grain mash converted almost completely near 100% based on Kai's first wort gravity chart, I had 13.6 Brix on the refractometer for 2.35qt/lb.  The older grain only reached 11.7 Brix.  the initial mash pH of the older grain mash was 0.1-0.2 higher, which may have contributed.  I probably should've adjusted with some lactic to get it in line with the other mash, but it was too late by the time I decided I should've adjusted.  I ended up extending the mash a bit and extending the sparge to get the gravities close (1.049 v 1.046). 

 

I also noticed the older grain batch did not produce as clean of a cold break.  This could have been due to slightly different quantities of Whirlfloc (I didn't measure carefully), or some side effect of extended mashing/sparging.  I'm not 100% sure.  The clear wort from the older batch, while mostly clear, had a slight noticeable haze compared to new grain wort.

 

Both were fermenting nicely as of this morning, more to come...

[positiveContact]

so was the old batch all old grain and the new batch was all new grain?

[neddles]

If the old grain batch had incomplete conversion then couldn't the haze simply be unconverted starch?

 

What was the new grain pH? Depending on how high the new grain pH was having a pH 0.1-0.2 higher could have been closer to pH optimum than the new grain batch.

Edited by nettles, 20 July 2015 - 12:05 PM.

[3rd party JKor]

so was the old batch all old grain and the new batch was all new grain?

 

Yes

 

 

If the old grain batch had incomplete conversion then couldn't the haze simply be unconverted starch?

 

What was the new grain pH? Depending on how high the new grain pH was having a pH 0.1-0.2 higher could have been closer to pH optimum than the new grain batch.

 

It could be unconverted starch, but I saw the difference in the whirlfloc effectiveness and related it to that.

 

I measured pH via colorpHast, new grain pH was ~5.1, old grain pH was ~5.3.  using the typical colorpHast offset of +0.3, the old grain batch *could* have been above ideal conversion range.

[Brauer]

Yes

 

 

 

It could be unconverted starch, but I saw the difference in the whirlfloc effectiveness and related it to that.

 

I measured pH via colorpHast, new grain pH was ~5.1, old grain pH was ~5.3.  using the typical colorpHast offset of +0.3, the old grain batch *could* have been above ideal conversion range.

Higher pH alone might be enough to explain the decreased protein flocculation.

 

I have to wonder if the higher pH is due to age or just variation between 2 lots of malt?

[3rd party JKor]

Higher pH alone might be enough to explain the decreased protein flocculation.

 

I have to wonder if the higher pH is due to age or just variation between 2 lots of malt?

 

 

Yes, you can see why the experiment wasn't perfect. 

 

It'll end up just being a step in the process.  Next up are some mini mash experiments that are a little more controlled.

[Brauer]

Yes, you can see why the experiment wasn't perfect. 

But, still, very interesting.

 

Believe me, after 30-something years as a research scientist, a perfect experiment is a rare and elusive thing.

[3rd party JKor]

I don't have the time to design and execute even a half-assed experiment to decide if it's worth it to use some old grain.  It's really just an A-B comparison to see if it's good enough.  Now that a potential conversion issue came into the picture, i'll chase that down.  If I can get good conversion on a mini-mash with proper pH, I'll probably just put the check mark there and decide based on the finished beer.

[Brauer]

I don't have the time to design and execute even a half-assed experiment to decide if it's worth it to use some old grain. It's really just an A-B comparison to see if it's good enough. Now that a potential conversion issue came into the picture, i'll chase that down. If I can get good conversion on a mini-mash with proper pH, I'll probably just put the check mark there and decide based on the finished beer.

Yeah, and an A/B comparison is all you need, in most cases. I've had a lot of success with older base malt; maybe out to 4 years or more. I do store my grain well - cool and dry, in airtight containers with desicant (in most cases).

Edited by Brauer, 21 July 2015 - 09:03 AM.

[3rd party JKor]

Just did a gravity check on these beers as I'm going to be moving to kegs and dry hopping this weekend.  Both beers fermented out well, the old grain batch went from 1.046 to 1.009 and the new from 1.049 to 1.010.

 

Both taste really nice, though the malt character is different.  That's expected as the base grain was not the same.  CMC Pale Ale (old) vs Rahr 2-row (new).  The well regarded maltiness of the CMC pale ale definitely comes through.  The Rahr batch has the more forward hop flavor and I'm getting more body from the CMC batch.  The lower gravity of the CMC batch is letting the bitterness through more as well.  Just slightly, certainly not in a bad way.

 

Thus far I'd say they are both good beers...but *much* more testing is required. 

 

I may send these in for judging, just out of curiosity.  Maybe.

 

 

ETA:  The earlier mentioned clarity issues followed through to the fermented beer.  The older beer is noticeably more hazy.  Although the new beer *very* clear at this stage and the older beer is only very slightly hazy.  As far as appearance, neither beer would give me any concern.  Not that I have much concern for a little haze, but I wouldn't consider either a 'problem'.  The older beer will probably clear out nicely in a few weeks.

 

ETA2:  These beers also had Clarity Ferm added at pitching, so presumably these beers are gluten free. 

Edited by JKor, 31 July 2015 - 08:52 AM.

[denny]

Doesn't seem like you can attribute the cloudiness to the age of the malt since you used 2 different malts.

[positiveContact]

Doesn't seem like you can attribute the cloudiness to the age of the malt since you used 2 different malts.

 

indeed - this is page 3 information JKor!

[3rd party JKor]

Doesn't seem like you can attribute the cloudiness to the age of the malt since you used 2 different malts.

 

 

No, I don't think that's attributable to the age of the malt.  If anything it's the quantity of whirlfloc used.  The whirlfloc tab didn't break apart evenly and the 'new malt' batch got the bigger chunk.  I didn't think it would make a difference because supposedly one tablet is enough for a 10 gal batch.  Both 2.5 gal batches had well over 1/4 of a tab, so I wasn't concerned until I saw the difference.  The new batch may have had as much as 50% more WF.  These are also older whirlfloc tabs, perhaps they've lost some activity and needed that extra amount that the new batch got to be effective.

[3rd party JKor]

indeed - this is page 3 information JKor!

 

 

I thought I had mentioned that earlier but I don't see it.  I had the CMC from North Country Malt and just got whatever I could from the LHBS, which was Rahr 2-row.

[denny]

No, I don't think that's attributable to the age of the malt.  If anything it's the quantity of whirlfloc used.  The whirlfloc tab didn't break apart evenly and the 'new malt' batch got the bigger chunk.  I didn't think it would make a difference because supposedly one tablet is enough for a 10 gal batch.  Both 2.5 gal batches had well over 1/4 of a tab, so I wasn't concerned until I saw the difference.  The new batch may have had as much as 50% more WF.  These are also older whirlfloc tabs, perhaps they've lost some activity and needed that extra amount that the new batch got to be effective.

 

I have to doubt that the small difference in amount of whirlfloc would account for that.  Maybe difference in the S/T protein amounts in the 2 malts.