by Kravin » Wed May 08, 2013 9:27 pm
OK quick and VERY rough crash course:
Mashing is the process of converting malted grain (starches) into sugars via the use of moisture and temperature using enzymes.
So in nature; a grain falls to the ground and absorbs moisture from the soil, then the sun heats it up which activates enzymes within the grain, which in turn reacts with the starches and converts them into sugars. The grain then uses that sugar as a nutritional source to sprout, establish itself in the soil and grow into a plant. which then starts the cycle again.
Maltsters collect grain and add moisture and heat to it so the enzymes are activated. then they suspend the process by kilning it at about the time the grain is ready to sprout. This is then called malted barley\wheat\rye etc.
What we are doing when we mash, is crushing the grain to release the starch, mixing it all together with warm water into a porridge and then activating the enzymes to 'eat' the starches, converting them into sugars for our yeast to 'eat' and then turn into alcohol.
so, things you'll need:
something to crush your malted grain or any other adjuncts you intend to brew with.
an insulated vessel that will maintain a constant even temperature for over an hour, or a way of maintaining a constant even temperature for that time.
A way to separate the fluid (wort) from the grain once the mashing process is finished (fine mesh bag, pillow case, false bottom, bucket with finely drilled out holes or slots, some sort of sieve).
First, crush your grains.
Most home brew shops that supply grain can also mill it for you too. if you have your own mill, make sure the crush is enough to separate the endosperm (white bits) from the inside while still keeping the grain hull as intact as possible.
this will allow the hulls to act as a filter as well as allow to the water to flow a lot better when rinsing (sparging) the grain. As some insurance, ask the home brew store to throw in an appropriate amount of rice hulls into the grain bill. this will aid in sparging without adding anything else to flavour. this would be especially true if you're using rye or oats, or anything that tends to go gluggy when mixing in warm water.
Batch size.
How much wash are you going to make?
for an all grain mash, the grain will absorb roughly 1L per 1Kg of grain.
so if we were making 40L of wash with 12Kg, we will need roughly 52L of water.
The Mash
for our 40L batch, lets throw say, about 35L of water at around about 70C.
then add your grain and mix well to avoid any clumps (doughballs).
the consistency of the mash should be like a chunky soup or a loose porridge so add some water if it's looking a bit dry.
for the sake of this crash course, we're aiming at holding the mash at 62C, so have some boiling water and some cool water on hand to adjust the mash temp accordingly.
now you need to hold it there for about an hour. depending on how your insulating your mash tun (insulated vessel) you might need to keep adding some boiling water and mixing to maintain that temp.
After the hour, throw some boiling water in there to bring the temp up to about 68C and let the grain bed settle for 5 minutes.
then drain\sieve\strain the wort into another vessel
Sparge
the rest of the water we have laying about, have that ready at about 75C and dump it into the grain, mixing well. let the grain bed settle again for 5 minutes and drain\sieve\strain into the vessel the first runnings are in.
you should be pretty close to your 40L batch size.
Check your gravity. if your low, most home brew shops sell LDME (light dry malt extract) or LME (liquid malt extract). this is basically what you have drained into the vessel, only it's been dried and powdered or condensed into a sugary syrup. you can use this, or sugar or dextrose or something fermentable to raise your gravity or dilute with water to lower it.
Ferment
Now this is where it's a little bit grey for me.
it looks like most distillers just ferment this out 'as is' with good results.
optionally you can boil it for say 15min or up to an hour for protein coagulation and leave that behind in the kettle when you transfer it to cool.
if you opt to boil it, you'll need to allow for evaporation and for the stuff (trub) in the bottom of your kettle and adjust accordingly to your batch size.
depending on how vigorous your boil is, you can allow for up to 10L over the hour or as little as a hundred ml over 15min.
Adjuncts
if you wanted to use corn, rice or anything without the Amalayse enzymes required for starch conversion in the mash, I would suggest about 2Kg of base malt (eg: pale malt) per 10Kg of corn\rice etc.
that should give you enough enzymatic action\diastatic power to still allow for starch conversion.
So that's a starting point for you, that will give you some moderate results.
Hope that helps.
Please correct\adjust or add anything to the above if need be.
it's an up the guts noob guide to mashing, not supposed to be completely accurate...
Kravin