Iodine test
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Not unless you do something incredibly "off piste" 
Cheers!
Cheers!
Sorry - it's so cold today I was thinking of skiing already 
Anyway...there's a well traveled path - and then there's heading off the trail on your own.
With today's malts a decent crush, reasonable water to grist ratio, and holding even a ball-park temperature, will convert in way less mashing time than most traditional recipes provide...
Cheers!
Anyway...there's a well traveled path - and then there's heading off the trail on your own.
With today's malts a decent crush, reasonable water to grist ratio, and holding even a ball-park temperature, will convert in way less mashing time than most traditional recipes provide...
Cheers!
I believe he's saying unless you're doing something out of the normal no it isn't required. Anytime I checked for conversion with iodine it was complete. I don't even bother checking anymore.
See definition 1.1
https://en.oxforddictionaries.com/definition/us/off-piste
If you're using standard well-modified grains that are appropriately crushed, mashing at the correct temperatures for sacchrification, and mashing for typical amount of time, then conversion will be completed and no iodine test is strictly necessary...
I can be instructive to perform the test in 5 minute intervals so you can see it progress, but modern malts are probably fully converted at 15-20 minutes... So a 60 minute mash is practically guaranteed...
Unless, of course, you go off piste 😀
https://en.oxforddictionaries.com/definition/us/off-piste
If you're using standard well-modified grains that are appropriately crushed, mashing at the correct temperatures for sacchrification, and mashing for typical amount of time, then conversion will be completed and no iodine test is strictly necessary...
I can be instructive to perform the test in 5 minute intervals so you can see it progress, but modern malts are probably fully converted at 15-20 minutes... So a 60 minute mash is practically guaranteed...
Unless, of course, you go off piste 😀
Never been a fan of the iodine test, and never done it myself. The most often recommended method says to take only wort, and avoid grits in the sample. That's totally wrong, because conversion of soluble starches in the wort happens extremely fast, and the rate limiting step is gelatinization of starch in the grits. So, if there is any starch left after just a few minutes of mashing, it is in the grits. So, to do a proper test you must include grits in your sample, and it's best if you crush them a little as well. This will tell you whether or not you have really converted all of your available starch.
A much better way to monitor the completeness of the mash is to periodically measure the SG of the wort in the mash. Turns out that for any specific strike volume to grain weight ratio (I.e. mash thickness), the maximum wort SG is almost constant (ref.) This allows you to quantitatively monitor your conversion efficiency during the mash by comparing your current SG to the max potential SG.
Brew on
A much better way to monitor the completeness of the mash is to periodically measure the SG of the wort in the mash. Turns out that for any specific strike volume to grain weight ratio (I.e. mash thickness), the maximum wort SG is almost constant (ref.) This allows you to quantitatively monitor your conversion efficiency during the mash by comparing your current SG to the max potential SG.
Brew on
"I have all the best words"
The hacking up of starches that'll render positive on an iodine test happens very quickly, especially in mash liquid. The hacking all the way into the smaller sugars takes longer.
I have done periodic iodine tests over the years. With the exception of ONE time using strictly malt flour and cold water, not at mash temp, it has never failed. I also do not bother any more.
Basically don't trust iodine to tell you the story. You're much better served relying on gravity as indicated above, and even then. If your goal is a high mashed (say 156-158F) highly unfermentable wort, you're probably good to proceed as soon as it's at gravity. For a highly fermentable wort (say 147-149F) it may take longer for beta to mop up after alpha and reach the level of fermentability that you want.
I have done periodic iodine tests over the years. With the exception of ONE time using strictly malt flour and cold water, not at mash temp, it has never failed. I also do not bother any more.
Basically don't trust iodine to tell you the story. You're much better served relying on gravity as indicated above, and even then. If your goal is a high mashed (say 156-158F) highly unfermentable wort, you're probably good to proceed as soon as it's at gravity. For a highly fermentable wort (say 147-149F) it may take longer for beta to mop up after alpha and reach the level of fermentability that you want.
Veldy
Member
I've not performed an iodine test more than once and the last time was more than twenty years ago!
If it's your first mash, I'd say try it if you've got iodine, but otherwise, just taste the wort. If it's sweet and not gritty, you're good to go as far as starch is concerned.
If it's your first mash, I'd say try it if you've got iodine, but otherwise, just taste the wort. If it's sweet and not gritty, you're good to go as far as starch is concerned.
Iodine will tell you if there is any starch left in the grains. If your grain is milled reasonably fine, there won't be much if any starch left after an hour long mash. If the iodine show starch left you can extend the mash to 90 minutes or more in hopes that the rest will convert.
No. I haven't done one in 18 years.
Sorry - it's so cold today I was thinking of skiing already
Anyway...there's a well traveled path - and then there's heading off the trail on your own.
With today's malts a decent crush, reasonable water to grist ratio, and holding even a ball-park temperature, will convert in way less mashing time than most traditional recipes provide...
Cheers!
Let's just go with piste-off. Yodaski.
What he said. I used to have a thing for highly dextrinous beers, and I was in and done. (Until, I think, it was in MBS where a study was shown on the MW of these sugars, and the sensory threshold. May be recalling totally incorrectly).
But beta-chewing at the tails does proceed more slowly. I iodine-tested every run, along with any other possible testing, because I thought I just looked cool.
