Iodine tests

[oldschool]

After i started this thread, i visited a small local brewery to buy some equipment. They don't do any testing like this.

 

[BierMuncher]

I mash a minimum of 45 minutes and up to 90 minutes for my dryer beers. My FG's finish between 1.003 and 1.012.

Never been a drop of iodine in my brewshop. Seems a needless extra step. I've also never seen iodine testing being done in local micro's. Refractometers...yes. But that's more for record keeping and tracking batch consistency and not to get a "yes or no" on whether there mash session was a success.

I say leave the iodine for treating minor cuts and simplify your brew process.

 

[The Pol]

I mash a minimum of 45 minutes and up to 90 minutes for my dryer beers. My FG's finish between 1.003 and 1.012.

Never been a drop of iodine in my brewshop. Seems a needless extra step. I've also never seen iodine testing being done in local micro's. Refractometers...yes. But that's more for record keeping and tracking batch consistency and not to get a "yes or no" on whether there mash session was a success.

I say leave the iodine for treating minor cuts and simplify your brew process.

I will be playing with iodine on my next batch, along with testing my PH throughout the process. Brewcast will be 10-27

 

[Catt22]

I mash a minimum of 45 minutes and up to 90 minutes for my dryer beers. My FG's finish between 1.003 and 1.012.

Never been a drop of iodine in my brewshop. Seems a needless extra step. I've also never seen iodine testing being done in local micro's. Refractometers...yes. But that's more for record keeping and tracking batch consistency and not to get a "yes or no" on whether there mash session was a success.

I say leave the iodine for treating minor cuts and simplify your brew process.

I did the iodine test the first few times I brewed all grain batches. Never got a starch presence indication at all. I quit doing the test altogether as it seemed to be a waste of time. I've never had a mash not convert and I realy don't see how it could not convert so long as you don't screw up the mash royally somehow. I did recently use Kaisers FW mash efficiency formula mostly out of curiosity. It indicated 100% conversion. Now, I don't plan to check for conversion in the future unless some kind of problem crops up which I doubt. Has anyone here had a mash fail to convert?

 

[The Pol]

I dont think this is about not converting the mash, but incomplete conversion. I am interested in how long it takes to convert my mash, I want to get some #s. If I am fully converted at 30 mins, I wont mash for 60 obviously.

I will be using Kaisers sheet, iodine and testing PH (digital) for my upcoming mashes to get some #s to work with.

 

[Catt22]

I dont think this is about not converting the mash, but incomplete conversion. I am interested in how long it takes to convert my mash, I want to get some #s. If I am fully converted at 30 mins, I wont mash for 60 obviously.

I will be using Kaisers sheet, iodine and testing PH (digital) for my upcoming mashes to get some #s to work with.

I think you will discover that the conversion is complete at 30 mins and possibly less. I always mash for at least 60 mins and often for 90 min as I have read that there are some other beneficial reactions taking place beyond the basic starch to sugar conversion. I did once do a 20 min mash just for grins and the conversion was complete based on the iodine test. The beer turned out fine and it placed second in a big competition. The short mash duration certainly did no harm in that case, but the result could be much different for various recipes. I'm never in a hurry when brewing, so I routinely go 60 minutes or longer.

 

[shortyjacobs]

Worth noting that the reason the "micros" don't do a lot of things is because their process is well established. They screw around every once in a while with new recipes, but for the most part it's tried-and-trues.

If you do the same recipe over and over, then you don't need to be as picky with testing things. For folks like us who make different recipes nearly every week, I would expect the extra data can be useful, no?

That said, iodine, hydrometers, and handheld refractometers are for wussies. I'm getting an HPLC and a 2 ghz NMR machine to measure conversion, concentration of sugars, and alcohol content.

 

[Kaiser]

Has anyone here had a mash fail to convert?

I had that happen with 100% dark munich mash beers. When the mash is stubburn and doesn't show a negative iodine test I check the wort going into the kettle. Mostly that one turns out fine and I'm not concerned about starches in the kettle. I also like to see that large decoctions convert or at least nearly convert before I bring them to a boil.

2-row and other lightly kilned malts should not have that problem at all.

I'm surprised that there are micro brewers who don't do that test. It seems like a cheap insurance even though it is very likely that there is no issue.

As I said before, a brewer should know what the iodine test does and what it doesn't do. He/she should also know how to do that test correctly and interprete the results. Just like he/she should know how to use a hydrometrer. If the test is done for every batch is up to the brewer.

Kai

 

[The Pol]

I have never tested for conversion... never really cared to. But with my system repeatability within +/-1% eff. I want to start looking at when I am converted, where my PH stands during the process etc. If I can get a better understanding of what is going on and when... that can only improve my process, or future manipulation of the process.

I would also attempt cutting my mash shorter. From 60 to 30 minutes before I begin my mashout, if possible.