Recirculating Mash Question

[Grizybaer]

By longer sugars, u means longer carbs that are not as long as starch But not as short as simple sugars. Is there any reason recirculating would hinder this conversion?

 

[maida7]

The longer sugars are called dextrines. A wort can be full of dextrines and not contain any starch. Dextrines are not easily fermentable but they can be further broken down into smaller chain sugars like maltose. After starch is converted the wort will have a mix of dextrines and maltose (and other things). More dextrines = less fermentable and fuller body beer. More maltose = more fermentable lighter body beer. Depending on the temp of the mash you can control the balance of dextrines to maltose.

That is a very simplified version.

I don't think recirculation would hinder any of the enzyme action. but... if the recirc drops the temp... Temp makes a big difference to enzymes so consider how you will maintain your temps if you are recirculating.

 

[TrickyDick]

My mash tun is a 10 gallon cooler and not fired. So, I couldn't re-heat when temps drop. I recently bought a pump and was going to try to expand its use into the mash steps. You know, gotta try to show a little ROI to SWBO. I would only be using it for a few minutes to vorlauf, not recirc the entire mash.

I once built a stem injection system with a Presto pressure cooker and a 1/4 copper tube to step mash in the Gott Cooler I had at the time. I don't recommend it is you use a false bottom however. Also generated a lot of teig.

TD

 

[TrickyDick]

I think that iodine test will be false positive in wort with unconvertable malt (like crystal and carapils).

I think that many brewers are using bad iodine solution, which in my experience varies in its ability to detect starch.

I recently switched to a new solution and it was positive after an hour. and after 90 min, and so on, until I gave up at 3 hours and just finished the brew session. I did NOT cook my mash enzymes either. I think it was positive because the iodine solution (Mucho Expensivo) was high quality discarded based on expiry dates from work and I took home to brewery therefore. When I compared to crapola solution I had that was years old it was negative when the HQ stuff was insanely positive.

Bottom line for me, I am going to mash for an hour, maybe more if its a really really light style beer at a low mash temp, or if I am doing a step mash. I am going to do an iodine test. I am not sure how I will modify the mash schedule as of yet, since I have this new very sensitive iodine solution, its causing me to re-think my process. Besides, an hour mash gives more time to clean the fermenters, and Relax and Have A HomeBrew too!

TD

 

[orangehero]

In my experience, the iodine test can be finicky and isn't very useful.

Also dextrins are not fermentable. S. cerevisiae can metabolize glucose, maltose, and depending on strain varying ability to metabolize maltotriose.

From braukaiser:

Aside from producing a wort of desired fermentability it is the goal of mashing to reduce the maximum length of dextrins in the sweet wort to less than 9 glucose molecules for unbranched and less than 60 for branches chains. At this point they don't show a reaction with iodine anymore and the wort or mash is said to be iodine negative. If that is not done and these long glucose chains are carried over into the beer, the beer may develop a so called "starch haze". Despite its name in most cases this haze is not caused by starch but by long dextrines which become less soluble and precipitate in the presence of alcohol. Those dextrines give a red to purple color reaction with iodine.

 

[grumpybrewingco]

I have wondered if recirculation during step mash makes a difference as well. I am making a Belgian Wit tomorrow. Sacc rest for 15 minutes at 120-125 then protein rest at 148 for 45 min. I am planning on recirculating for the entire time.
I usually recirculate for single infusion anyway.

 

[luhrks]

I continually vorlauf during my mash running a HERS system. My efficiency tends to be on the insane side (90%ish).

I don't mash for a set time. I mash until I hit my numbers, then start mash out.

 

[baer19d]

I have a propane burner direct heated mash tun and I recirculate whenever the burner is on so I don't scorch it and it seems to work fine.

 

[Noladave]

I have the same problem. And haven't figured it out. I use a keg for a mash tin as soon as I turn my pump on the temp drops. I can turn my burner on low and the temp will go up. Only problem is it keeps going up. Anyone else have this problem?

 

[Noladave]

I have a lot of hear loose when I do it. I use a keg for a mashton and use a burner to hear it. But wow the heat drops fast. I turn my burner on and the heat rises but doesn't stabilize.

 

[Sadu]

I tried a 30 min mash and boil once on a recipe I have brewed twice before. Efficiency went from 80%ish down to 63% which is by far the worst I have ever got. pH was good, and crush was good. Suffice to say I'll be sticking with 60-90 min mashes.