Weird question, but I'm in the middle of a 'forced experiment'...

[SemperFermentis]

Was trying parti-gyle, not for the first time but did experience something new. Didn't even come close to my predicted OG. Added some more grain to the second run, as scheduled, and now I'm not getting a complete conversion (via the iodine test). Is it possible that I could have brought the original temp up high enough to prevent a conversion on the second pass, despite the fact that I'm in 'normal' temperatures again? (152 degrees F)

Just wondering if this is possible, or that I'm just impatient...could definitely be impatience, however now I've got a question without an answer...

 

[nmenninga]

Yes, you can denature enzymes by raising the temp too high, and there's no bringing them back. They are not like yeast where more time is always a good option.

 

[SemperFermentis]

Yes, you can denature enzymes by raising the temp too high, and there's no bringing them back. They are not like yeast where more time is always a good option.

Yes, which is what I think might have happened. My question is more specifically related to the additional grain that I added to the mash for the second round, wouldn't that add more enzymes to the mash and result in a second conversion?

Or, would the temperature somehow affect the starches/sugars from the original mash and prevent a conversion from taking place?

 

[nmenninga]

Fresh grain, if well modified, should resume the work, no problem. Higher temps should actually make remaining starches more convertible, in theory.

A true scientist would do the experiment. How did it work out?

 

[SemperFermentis]

Fresh grain, if well modified, should resume the work, no problem. Higher temps should actually make remaining starches more convertible, in theory.

A true scientist would do the experiment. How did it work out?

Oh, trust me, I tried! I'm definitely of the adventurous type, but with that much grain on the line I think anyone would have given it a shot. Honestly, I never got a full conversion, and I think it would be quite a bit more accurate to say that it probably never converted at all. The wort that I pulled from the mash was almost milky, as if I was doing a wit beer, and the iodine test went black pretty quick.

I ended up staying up until about 3AM in order to boil off enough water from the first wort to reach an appropriate gravity to mix with the second runnings. In the end, I did get about where I wanted to be, however smaller beer did indeed turn out smaller, about a gallon less than I intended it to be, volumetrically speaking.

I'm going to post the recipe this evening with my notes and see if anyone wants to take a gander at what the heck went wrong.

 

[nmenninga]

Maybe you drove your pH too far down, it is a stumper, though.

 

[SemperFermentis]

Maybe you drove your pH too far down, it is a stumper, though.

That's a good suggestion, which is why I'm in the process of obtaining a pH meter, FINALLY.

Here's the recipe I used:

14 lbs White Wheat Malt
8 lbs Pale Malt (2Row American)
1 lbs Crystal 40L
8 oz Carared
8 oz Honey Malt
Nearly a pound of rice hulls

I mashed this in with 162F water at a ratio of 1.25 qts/lb and obtained a mash temp of 150. This was easily maintained with the amount of grain and water in the tun, which was a 10 gallon igloo with a false bottom.

Beersmith told me to expect an OG of 1.110, which I usually obtain or get better due to my lengthy mash times (I go until I get a full conversion). I got a full conversion, (although I'm wondering if I missed something now, a mystery like this will leave you to question everything but I'm pretty sure I got a full conversion)

Measured OG, taking into account temperature, came out at 1.072. That's a pretty large margin of error. I even added some 170F water to the wort and ran it back through, nothing better.

At this point I'm thinking that my sparge wasn't normal as per my usual procedure. Usually I bring up the mash temperature to 165F for the sparge by adding some water from my HLT, however with this grain bill I didn't have the room that I normally do in order to do this so I had to start pulling wort at about 155F. I'm thinking, after talking to some people, that I might have been dealing with some channeling or maybe my mashout temp wasn't high enough to dissolve all the sugars.

I then went on the assumption that I didn't have a full conversion, which looking back now was probably not the problem. I added about 8 more pounds of grain and re-mashed. This grain, I'm quite certain, didn't convert. 2 hours of boiling down the first wort to bring up the gravity (boiled off about 2 gallons) and mashing the second time yielded no conversion.

By this time it was 11 o'clock and I just said 'F-it' and pulled the second wort off and added it to the first wort. The end product was (funnily enough) a 1.116 post boil hopped wort that is fermenting nicely, and 4 gallons of 1.060 that is also fermenting well.

At this point I know that I have beer, but it was one hell of a process. I hope it's not awesome because I have no idea how to do this again, lol! But it should be interesting with the lengthy boil and such.

Damn this got long winded, but here's the recipe and what happened. Any input would be appreciated.

 

[Denny]

More proof that the iodine test isn't a good indicator.

 

[nmenninga]

Are you sure the wheat was malted, not plain?

 

[SemperFermentis]

Are you sure the wheat was malted, not plain?

Yes, it was white wheat malt. I've worked through about 75% of the 50lb bag I purchased, this was the first time I had an issue.

 

[SemperFermentis]

More proof that the iodine test isn't a good indicator.

Wow, must have missed this one. I'm going to have to go back and look into that. (...and the knowledge base keeps growing...)

 

[Denny]

Wow, must have missed this one. I'm going to have to go back and look into that. (...and the knowledge base keeps growing...)

it is so easy (and common) to get false results with the iodine test that I avoid it and advise others to do the same.

 

[nmenninga]

I use pH paper, it isn't very precise, but it does give you an indication if you are out of range. Cheaper than a probe, may help you decide if a probe is a good investment.

 

[IL1kebeer]

What was your pre-boil volume and mash efficiencyin BeerSmith?

I entered that recipe in BeerSmith with 75% efficiency and with a preboil volume of 6.2 gallons. The preboil gravity that it calculated was 1.075, just a bit higher than what you got.

Is BeerSmith telling you that your preboil gravity is 1.110 or that your OG is 1.110? With that grain bill you would have to be doing 3 gallon batches for a preboil gravity of 1.110 and a preboil volume of around 4 gallons.

 

[SemperFermentis]

What was your pre-boil volume and mash efficiencyin BeerSmith?

I entered that recipe in BeerSmith with 75% efficiency and with a preboil volume of 6.2 gallons. The preboil gravity that it calculated was 1.075, just a bit higher than what you got.

Is BeerSmith telling you that your preboil gravity is 1.110 or that your OG is 1.110? With that grain bill you would have to be doing 3 gallon batches for a preboil gravity of 1.110 and a preboil volume of around 4 gallons.

I will have to check that when I get home, however it's totally possible that I could have screwed something up in Beersmith, I've only just recently been starting to use it. If this is the case, then it would make sense I suppose.

 

[SemperFermentis]

it is so easy (and common) to get false results with the iodine test that I avoid it and advise others to do the same.

So how do you ensure that your conversion is complete...or do you at all?

 

[Denny]

So how do you ensure that your conversion is complete...or do you at all?

By mashing at a proper temp for a proper amount of time! If I'm under 150, I mash for 90 min. Over 150, I mash for 60 min. Unless you totally screw up, you WILL have conversion in that amount of time. I also usually use Kai's conversion efficiency chart to ensure that I have full conversion. But that's more for giggles than anything else.

Why would you think you didn't have conversion?

 

[SemperFermentis]

By mashing at a proper temp for a proper amount of time! If I'm under 150, I mash for 90 min. Over 150, I mash for 60 min. Unless you totally screw up, you WILL have conversion in that amount of time. I also usually use Kai's conversion efficiency chart to ensure that I have full conversion. But that's more for giggles than anything else.

Why would you think you didn't have conversion?

Well, because that was just the school of thought that I was brought up in I suppose. The basic idea was just to check and make sure.

In my earlier experience some of the recipes call for 60 min mashes, however I noted that I didn't have as full of a conversion as if I went for 90 min. I just kept checking on force of habit. (Heavy chemistry, metrology, engineering background = anal + force of habit)

I guess based on what I know now, these individuals were merely trying to control their attentuation to some degree by "cutting the mash short"?

 

[Denny]

Well, because that was just the school of thought that I was brought up in I suppose. The basic idea was just to check and make sure.

In my earlier experience some of the recipes call for 60 min mashes, however I noted that I didn't have as full of a conversion as if I went for 90 min. I just kept checking on force of habit. (Heavy chemistry, metrology, engineering background = anal + force of habit)

I guess based on what I know now, these individuals were merely trying to control their attentuation to some degree by "cutting the mash short"?

Maybe, but mash time is a very small, uncertain way to control attenuation. A longer mash will break down more long chain dextrins and produce a more fermentable wort, but grist composition and especially mash temp is a much more reliable way to do that. Believe me, I understand OCD...I'm so OCD that it's actually CDO because the letters are in the right order! But if you're an experienced brewer (or someone who's mashed for 5 hours becasue the iodine test STILL didn't show conversion!), you know that the mash is gonna work. Trust yourself and your methods, not a questionably reliable test.

 

[IL1kebeer]

I will have to check that when I get home, however it's totally possible that I could have screwed something up in Beersmith, I've only just recently been starting to use it. If this is the case, then it would make sense I suppose.

Go to the "Mash" tab in your recipe and look at the preboil volume and preboil gravity at the bottom right of the application. I suspect that the volume is between 6 and 6.5 gallons and the preboil gravity is close to 1.072. It will probably be ballpark because this depends on your equipment settings and est. efficiency.

 

[SemperFermentis]

Go to the "Mash" tab in your recipe and look at the preboil volume and preboil gravity at the bottom right of the application. I suspect that the volume is between 6 and 6.5 gallons and the preboil gravity is close to 1.072. It will probably be ballpark because this depends on your equipment settings and est. efficiency.

Good to know Denny! I've seen you on here sir, so I'm honored you took the time to help me out with this.

Followed the directions, and it seems like you're probably right. I have Pre-Boil volume of 6.5, and have a set efficiency of 84% (Whiiiiiiiich I should probably change) Pre boil gravity is 1.091, so I think that we've gotten to the bottom of my problem.

Now I just need to figure out why my second grain addition didn't mash correctly, although I suspect that's a temperature issue. I'll have to try this again, and take better notes while paying closer attention. Looks like I ultimately need to educate myself up on some BreerSmith.

Thanks to everyone for their input on this, and if there's anything else to consider here, I'm all ears!

 

[IL1kebeer]

I think I made a mistake when I entered your recipe. I put 8oz of pale malt instead of 8 lbs.

Here is a BeerSmith podcast that explains more about high gravity brewing. At around 6 minutes into it I think they start talking about the problems that you are facing.

Sorry for the confusion.

http://beersmith.com/blog/2012/02/2...-beers-with-john-palmer-beersmith-podcast-33/

 

[SemperFermentis]

I think I made a mistake when I entered your recipe. I put 8oz of pale malt instead of 8 lbs.

Here is a BeerSmith podcast that explains more about high gravity brewing. At around 6 minutes into it I think they start talking about the problems that you are facing.

Sorry for the confusion.

http://beersmith.com/blog/2012/02/2...-beers-with-john-palmer-beersmith-podcast-33/

Thanks for the link, I'll be sure to check it out. I'm probably suffering from a lack of knowledge base on the program, but it still seems like you're barking up the right tree.

Weird though, as I went through my notes I noticed that I only collected approximately 5 gallons in my first runnings. If I had continued to 6.5, this would have lowered my pre boil OG, right? I think I'm just going to have to try this recipe one more time, after some serious education in the BeerSmith category.