by Haza » Tue Jan 11, 2022 9:16 pm
Who hoo, finally something I know about! :D
I know about this from making when making stupid American cream ales!
As most all grain beer brewers already know malted barley has an excess of protein, that corn and rice don't and you can use this to your own advantage to make a mash that will be converted easily by the enzymes in the malt.
Corn and rice starches don't gelatinise at mash temperatures and aren't available to the malt enzymes for conversion into sugars. Boiling the cereal gelatinizes the starch, but then you have cooked rice or cornmeal mush, and those are hard to handle in a brewery – think sparging (rinsing) nightmare!
Plus, when they cool, they become really stiff (like a porridge) and hard to move or incorporate into the mash. The secret turns out to be malt. By adding a small amount of malt to the cereal and mashing a short time before cooking, the cereals become quite thin and stay that way there’s a whole stack of reading you can do on betta and alpha amylase but - let’s not go down that rabbit hole.
With modern malts you don’t need to add as much as they did 100 hundred years ago was to use 30% malt by weight. The current practice of using only 10% of something with a high enzyme character like a pilsner or American ale malt – steer clear from caramel or crystal malts as they have had most of the enzymes that you want already caramelised with heat in the malting roasting process.
Use about 1.5 litres of adjusted water for every 500g of corn and increase that to 2 litres if you are going to use rice and corn meal should be cooked covered about 30 minutes with a lid on the pot Stir as you bring them up to a boil and occasionally during the boil, adding more water if necessary. It's best not to overcook rice, but corn can be cooked longer for more flavour and colour reactions to take place in the cooker if you want these.
Meanwhile, you have started the main, or malt mash, and timed it so just as the cereal mash is done, it is time to boost the temperature of the main mash. It's best to plan this ahead on paper.
The recommended mash schedule for the Barley main mash - mash in at 62 – 63°C, rest for 30-45 minutes (wrap the pot or kettle in old towels / sleeping bags) while boiling the cereal mash, add the cereal mash, which brings the combined mash to about 73-74°C (you may need to add some boiling water or heat), and rest another 30-45 minutes. This produces a wort with high fermentability.
If you want to go even further once the mash has cooled and you have sparged you can also get a dry enzyme form brew shops that works at fermentation temperatures that will further break down the non-fermentable sugars in your wash and really drive down the final gravity.
Hope that helps
Cheers