Adventures in Nixtamalization

[gray]

Tim this is an awesome post. I have been studying nixtamilization for awhile and not had the time to play with it.
You have inspired me now. And eliminated a lot of trial and error. Thanks to all.

[Walk]

What about burning corn cobs for ash?

[steev]

Sure.

[oxbowfarm]

I have my first batch of ash nixtamalized corn ready to be rinsed off this morning. I estimated based on wood ash "liming effect" recommendations to use about three times more ash than I've been using pickling lime. So I added 6 tablespoons fresh wood ash. There is still a very tiny amount of charcoal in the ash that was broken small enough to sift through the aluminum window screen I used as my mesh. Pericarp breakdown was a bit slower than I would have expected from pickling lime, took approximately 20 minutes at a simmer to break down the pericarp on White Flour Grex. This is about 5 minutes longer than I've been experiencing with pickling lime. I will increase my ash on the next batch to 7 or 8 tablespoons.

I also have been thinking a lot about the question of "what kind of ash do you use?" Intuitively, I agree with steev that it should not matter at all what type of wood you are burning, since only minerals are going to be left in the ash.

I found another really great resource discussing ash composition. If you want to geek out on wood ash, this is a great article to read. In essence is says that wood ash is primarily Calcium and Potassium compounds with all other minerals being a lower percentage. The exact ratios of all the minerals in a specific wood ash sample, and the compounds which they are present in, are dependent on the species of wood being burned and the temperature to which the ash is heated. Ash is primarily carbonates above 500 deg C but carbonates are degraded as temperature increases towards 1000 deg C. By 1000 deg C all carbonates are converted to oxides. If the ash gets heated above 1000 deg C it will slowly volatilize Potassium, Copper and Boron which will reduce in percentage the higher the temp or the longer the ash is held at the high temperatures.

It also looks like if you want to make a very specifically high mineral ash, you can seek out a high mineral species, or specifically burn bark vs wood. Bark is very high in mineral content, especially Calcium minerals.

Basically this article makes a good case that it would be perfectly acceptable to use conifer ash to nixtamalize corn. In fact, the conifer tested had a higher Potassium content than the hardwoods tested.  You could also make the argument that ash nixtamalization is nutritionally superior to using calcium hydroxide based on the broader spectrum of minerals present in the ash.  Pickling lime is likely very close to pure Calcium hydroxide or Calcium and Magnesium hydroxide.  Wood ash contains (in decreasing order of concentration) Calcium, Potassium, Magnesium, Sulfur, Phosphorus, Manganese, Zinc, Iron, Aluminum, Sodium, Silicon, Boron, and Copper. 

[Walk]

Nov 24, 2014 8:27:53 GMT -5 oxbowfarm said:

I found another really great resource discussing ash composition. If you want to geek out on wood ash, this is a great article to read.

I just checked out this link and got a virus alert from my anti-virus software. May be a problem?

[oxbowfarm]

I did not get a virus warning, but I'm on a 12 year old Dell.

The title of the paper is "WOOD ASH COMPOSITION AS A FUNCTION OF FURNACE TEMPERATURE" from Biomass and Bioenergy Vol.4, No. 2, pp. 103-116, 1993

There's possibly an alternate source to view that paper than the link I shared.

[oxbowfarm]

In the ongoing quest to understand tortillas and Mexican corn, it is worth looking at the corn section on the Biodiversidad Mexicana website.

They have all the current segregations of Mexican corn races, a description of the use and agroecosystem where the corn thrives, a map of the range of each race, and really great photos. There is a function to translate the text into English. I think it uses Google translate so it isn't perfect, but its good enough. This is the best source I've found to list the actual preferred uses for each corn in Mexican cuisine.

From what I can tell from searching through the site, Mexicans make tortillas out of almost every texture of corn. dents, flints, and flours. The only major type of corn they don't seem to make tortillas out of much are small seeded popcorns, but they do grind those up very commonly into pinole. I highly recommend the site. maicerochico had linked it to me a while back and I didn't appreciate it much because I didn't notice the translation button. With the text translated it becomes an awesome resource.

[oxbowfarm]

Found a nice video of ash nixtamalization, it isn't really a recipe, because its a video for teaching the Mohawk language. It has really good images of the basic process.

www.youtube.com/watch?v=fJd-oivL2Bc

[oxbowfarm]

Unfortunately I did not take a comparison photo of ash nixtamalized White Flour Grex and "cal" nixtamalized White Flour Grex. I will make sure and do so the next time. There are definite visual differences. The ashed corn is much darker in color, even after rinsing off the pericarp.

I would also say that I need to increase the amount of ash to get the same potency as I get with the lime. The pericarp did not perfectly all rinse off with my first batch of ashed corn, so I assume the solution needed to be stronger. In a recent conversation on Facebook I was told that traditional Mohawk ash nixtamalization recipes call for equal volumes of ash and corn. That is a lot of ash!

Flavor was very good, but not discernibly different from cal nixtamalized corn. The ashes stain the corn slightly around the tip of the kernel, a slight brownish tint. It isn't very noticeable unless you look at a batch of cal nixtamalized corn side by side. I will do some more corn both ways and get a picture to demonstrate.

[steev]

Being unconcerned about the cosmetic quality of the corn and intending to heat (and often cook) with a wood stove, I doubt I'll ever bother with cal or lye; besides which, I expect the depleted ash/pericarp solution to have fertilizer value.

[Walk]

Nov 30, 2014 9:31:05 GMT -5 oxbowfarm said:

Found a nice video of ash nixtamalization, it isn't really a recipe, because its a video for teaching the Mohawk language. It has really good images of the basic process.

www.youtube.com/watch?v=fJd-oivL2Bc

Thanks for posting this link. I had tried ash once but obviously didn't use enough of it. I've been using pickling lime since. I do put all of the rinse water on the compost to recover some fertilizer value from it.

I found it interesting that the Mohawk method makes hominy then dries it before milling, instead of wet milling. So what they're ending up with is masa harina? It sure is in a convenient form that way for storage and quick meal prep. A little faster version of slow food?

[oxbowfarm]

Dec 1, 2014 16:55:22 GMT -5 Walk said:

Thanks for posting this link. I had tried ash once but obviously didn't use enough of it. I've been using pickling lime since. I do put all of the rinse water on the compost to recover some fertilizer value from it.

I found it interesting that the Mohawk method makes hominy then dries it before milling, instead of wet milling. So what they're ending up with is masa harina? It sure is in a convenient form that way for storage and quick meal prep. A little faster version of slow food?

I'm not actually sure what the Mohawk do with the dried, milled, hominy flour/masa. I was surprised to see them milling it up at the end of the video myself. The only Haudenosaunee recipe I have for hominy uses the whole kernels in soup. There is a red pericarp, 8-row flour corn that I am planning to trial next year called Mohawk Red Bread corn, so the Mohawk seem to have a tradition of making some form of bread product with their corn. I don't really know anything specific about their corn usage traditions though.

[steev]

I would suspect that dried hominy is just handier to store than milled, further, I'll bet they made mush, as did California tribes with pounded acorns and horse-chestnuts, although they didn't need to leach the ground hominy, of course.

Holly mills corn flour which is primo for a thickener or a coating for fried flesh; milled hominy would work.

[oxbowfarm]

Ash Nixtamalization

I went with a 2:1 corn to ash ratio for this last batch. Half gallon water, 1 quart corn, 1 pint sifted ash (very fresh ashes and my White Flour Grex corn).


Since we'e burning wood now, I set the pot to heat on the woodstove. The main difference that made for this batch was, since the stove was running fairly hot, that the corn cooked for 15 minutes at a roiling boil vs a simmer like I had been doing on the range top. Thus the ring of charcoal bits and pericarp shreds on the side of the pot. This picture is immediately after removing from the heat. Next step is to let is sit overnight.


Here's the corn after rinsing and washing the next day.


Right off the bat I can say that this ratio made a VERY strong alkaline solution. The pericarps were mostly removed in the pot during boiling, long before I ever did the final rinsing step. I could feel the alkali on my hands saponifying my skin oil and making them slippery while I wash washing the corn. I will reduce the ash by half again for the next batch. Ashes are bulkier than cal, and there was a layer of muddy ash on the bottom of the pot, which you never see with cal. It required several extra changes of water to dilute the extra alkali and wash off all the excess ash. I can see why a 1:1 ratio might be traditional though. Ashes would be abundant, and you'd never have to worry about under-processed corn with so much extra alkali. But I'd like to use just enough to get the job done to make washing the hominy afterwards easier. I'd like to try this ratio with red pericarp corn though, to see how it behaves in much stronger alkaline solution.  I also would recommend not pouring the first rinses down the drain, you are likely to fill your trap with ash mud. I've been dumping those first rinses on the compost.


P.S. Update. This was WAY to much ash. There was a very strong, chalky bitterness which I attribute to excess unreacted alkali. It was edible, but unpleasant. This is the first batch of hominy/nixtamal that I will not be eating. It is going to the chickens. I am going to cut the ash in half or more on my next ash nixtamalization trial.

[DarJones]

If I am working the ratios right, you should try 3/4 cup sifted ashes, 1 quart corn, and 2 quarts water.