Skip to main content

How can I be sure my mash is really finished?

If you are new to all-grain brewing, or you're brewing a higher-gravity beer than usual and want to be sure the mash has converted all the available starches to sugars, here is an inexpensive but effective way to do it.

Before brewing, go to your local drug store and pick up a bottle of Tincture of Iodine.  That's the stuff often placed on cuts as an antiseptic.

When you think your mash may be finished, extract a small sample from it.  Add a drop of iodine to the sample.  If you see the sample turn dark purple or black, there is still starch in the mash to be converted.  If there is little to no color change, your starches should be fully converted to sugars.  Time to move on to the boil!

Below is a picture of what the test results look like.  The tube on the left contains starch and has turned a dark color.  The one on the right does not.

Image courtesy of imgarcade.com



Comments

Popular posts from this blog

Things I've Learned Brewing with The Grainfather, Part 2

In the last post, I shared an overview of The Grainfather, recommended equipment to use with it, and an overview of the brewing process.  In this installment, I'm going to talk specifically about mashing and sparging. Having brewed over a dozen batches with it, I'm finally becoming very comfortable with the device, the mash process, and how to get what I want out of it. I don't consider myself a "master" of it yet, though. For those who have never done all-grain brewing, I want to provide a quick overview of the mash process itself. Mashing - With or Without The Grainfather The goal of mashing is to turn the starches in the grain into sugars. More specifically, you want to turn the starches into a mix of fermentable and unfermentable sugars that provide the flavor profile associated with the beer you are brewing. A sweeter beer might warrant more unfermentable sugars. A more dry beer will demand few unfermentable sugars. To a great extent, controlling the

Brewing with The Grainfather, Part 3 - Cleaning and Overall Thoughts

In Part 1 of this series, I introduced The Grainfather and discussed how to use it for mashing and sparging.  In Part 2, we talked about boiling and chilling the wort with The Grainfather and its included counterflow chiller.  In this final segment, we'll discuss cleanup and overall thoughts about the device and its usage. Cleanup Once you've pumped the wort from The Grainfather into your fermenter and pitched your yeast, you're well on your way to a delicious batch of homebrew.  Unfortunately, you've still got some cleanup work to do. The cleanup process in my experience will take 20-30 minutes.  It involves the following tasks: Removing and discarding the grain from The Grainfather's grain basket Cleaning the grain basket, kettle, recirculation tube, and wort chiller Cleaning all the other implements used in brewing (scale, scoops, mash paddle, etc.) At the end of the brewing process, there will be hops bags (if you used them), grain and other residu

Chapman Brewing Equipment 7 Gallon Stainless Steel Fermenter

Chapman's 7-Gallon Stainless Fermenter Recently, I found the Chapman Brewing Equipment 7-gallon SteelTank stainless steel fermenter on sale on Amazon for approximately $110.  That's about half the price of the other stainless steel fermenter I own, Ss Brewing Technology's Brewmaster Bucket. In fairness to the Brewmaster Bucket, the Chapman fermenter lacks a number of features.  The Chapman has no legs underneath it.  It's not designed to stack multiple fermenters on one another.  It has no thermowell or thermometer.  It doesn't have a conical bottom to catch yeast and sediment.  It also doesn't have a spigot you can use for bottling.  So the extra $100 buys a few features you're not getting here. That said, there is nothing wrong with this fermenter.  It seems very well made from 304 stainless steel.  There are good strong looking handles.  The gasketed lid can be clamped down for sealing and safety when carrying.  It even ships with a 3-piece airlo