Using a Corona Mill to Make Fresh Masa

In keeping with the general theme of finding multiple uses for brewing related ingredients and equipment, I thought I'd write a quick post about an alternative use for Corona mills.  In fact, I shouldn't say 'alternative', since these mills are sold for grinding nixtamalized corn to make masa, and are being re-purposed by budget-conscious homebrewers like me for crushing grains.

To make masa you need dried field corn.  I've been using this stuff from Amazon, but when I get back from England I plan to see if I can find wholesale suppliers for all the unmalted grains I use in brewing and baking.  I also plan to try using this corn in some beer---either ground up into grits and boiled in a cereal mash, or maybe even in the form of mealy masa added straight to the mash.  But that's another post.

Once you have your dried corn, you need to nixtamlize it so that it will form a dough.  I first learnt about this process on an old episode of Good Eats, but recently I've been relying on the excellent description of the process in this post.  Nixtamlizing the corn involves boiling and soaking it in an alkaline solution: the most common way to do this is by using 'cal', which is also sold as pickling lime.  I add one tablespoon per pound of corn, make sure its well covered with water (it will expand as you soak it), then bring it to a boil for twenty minutes before letting it soak and cool overnight.

The next day you need to give the corn several rinses in clean water to get rid of the lime.  At the same time, you should try to agitate it or rub it together so that the hulls fall away from the corn (this will already have happened to most of them---they seem to sort of dissolve).  Then once the corn is clean and drained its time to get out your Corona-style mill.

Unlike brewing, we're not at all concerned to preserve any husk material here, so its fine to screw the mill down to its tightest setting.  I go down as tight as possible, so that it won't move, then back off a fraction and crush the corn.  Its a bit of work, and often frustrating as the mill works itself loose, but ultimately not that much effort.  The result is a mealy grain that compacts into a rough dough.

Now comes the hard part: do you want to run the grain through the mill again?  Lots of people recommend this, and it certainly leads to a finer texture in the finished product.  The problem is that milling the meal is much harder than milling the corn (at least with my Corona), because you have to force it into the drive shaft as you mill (it won't fall in by itself as grain or whole kernels do).  This makes milling the grain a second time significantly more difficult and time consuming.  I've done it four of the five times I've made masa, but on my most recent attempt I only milled it once, and I thought the results were acceptable in the tacos I made.

Once you have your meal, its time to decide what you want to do with it.  I've made tamales in the past, but the easiest thing (if you have a tortilla press) is to make tacos.  You work small amounts of water into the meal until it forms a smooth dough.  Be careful here: if you add too much at once, the dough will get sticky and it will be difficult to press it.  I've settled on a consistency I like through trial and error, but I get there by touch rather than specific amounts.  I then press golf-ball sized rounds of dough on a cast iron press lined with a cut-up ziploc bag.

Finally, I remove the bag and carefully peel off the tortilla: if you've got the consistency of the dough right this shouldn't be too hard, but sometime they stick, especially if the dough is wet.  I cook them on a wide griddle, following instructions from one of Rick Bayless's books: he has you lay the tortillas on part of the griddle set to low heat for about fifteen seconds, until they release from the metal.  Then you flip the to a hotter part of the griddle, cooking them for about 30-45 seconds on each side.  I like to transfer them to a basket lined with a kitchen towel at this point to steam for a few minutes.  After that, they're ready for filling!

I really like the results, but it is a lot of work, especially if you grind the meal more than once (this might be easier on a better mill).  We can get pretty good corn tortillas in the supermarket here (certainly much better than anything I ever had access to in England!), so this is only something I do when I have a bit of time on my hands.  That said, the masa seems to keep reasonably well vacuum-sealed in the freezer, so I've started making big batches and portioning it out for later use.  This means a lot of work up front, of course, but I think its worth it in the long run.