Grinding corn

Sweet Tatorman's picture

There was some recent discussion in another thread about grinders for corn. Rather than further hijack that thread I am starting this one specific to the topic to add my $0.02.
Except on occasions I am away from home, I eat something made from cornmeal I have ground [most typically cornbread] almost every day of the year. What I have been using for many years and highly recommend if you are serious about grinding frequently is a commercial coffee grinder of the type you see in grocery stores where you select and grind your own beans. There are two major companies which dominate the market for this type of grinder; Bunn and Grindmaster. All of my experience has been with various Grindmaster models. These things were built to last and are easy to maintain. My first acquisition was a Grindmaster model 500 which from the serial number was made in the mid 1930's. It still runs fine though is not my "daily grinder". That would be a model 875 which is only a few decades old. Current models include the 810, 835, 850, and the 875 among others. These 4 models differ only in the hopper capacity and all share the same motor and grinding mechanism. Interestingly the burr set in my 1930's model 500 is exactly the same as in these four current models though the grind size adjustment mechanism differs. If desired, it is possible to sharpen the burr set though this is not done in the commercial space where new replacement burrs are installed instead. . All that is needed is a cordless dremel type tool with a diamond coated grinding disc, a vise, and a couple of hours. The potential for sharpening the burr set is why I have stuck with Grindmaster vs the Bunn as what I have seen of the Bunn burr set design it would be more difficult to attempt to sharpen. There is a model 890 Grindmaster that has a different burr set design that also looks more difficult to sharpen.
Somewhat counter intuitively, the grinder draws more power with sharpened burrs than with unsharpened ones. The throughput increases even more though which results in a reduction in Whr/lb. Specific numbers for this. My Model 875 as received required 37 seconds and 8 Whr to grind a lb at my usual grind setting. Post sharpening it required 19 seconds and 7 Whr per lb. My usual grind setting is one click stop courser than espresso.
These grinders can be had very cheaply relative to their new prices. Restaurants, coffee shops, grocery stores go under on a regular basis thus making these available. These things are heavy! I've seen some go on ebay for less than the cost of shipping. I just now scanned the "completed" listings on ebay and saw a model 850 sold for $0.99 for local pickup only. If you are a bargain hunter you likely will do best with a local find.
Pictured below [photo harvested off of web] is a Model 875 and a pair of 835's. The models 810, 835, 850, and 875 look fairly similar but differ in height due to differing hopper capacity.

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Sweet Tatorman's picture

Mr B and I as well as some others here will remember these from the grocery stores of our childhood.
This was the first Grindmaster model I acquired.

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ClareBroommaker's picture

My first paid job was in a grocery store and it was often my job to clean out the chute and catch tray under that machine. I was not yet a coffee drinker, but my mother was, and my family was probably at its poorest at this time. So I used to bag up the "sweepings" and take it home to Mom. The grind, the roast, the brand-- didn't matter. Just mix it up and take what you get.

lathechuck's picture

Have you tried grinding anything other than corn? Oats, or wheat?

By the way, do you have any idea what accounts for the vast difference in price between $5/bushel wheat (bulk commodity, about 50 lbs.) and whole wheat berries for home milling ($25 for 10 lbs)? It can't just be the cost of unloading the barge into cute little bags.

Blueberry's picture

Nice machine! So if you grind corn with a coffee grinder what do you use to grind coffee? Only joking an being a wise a$$. Will have to be on the look out for a Grindmaster. Remember them at The A&P, Winn-Dixie and a little Mon&Pop store near the house.

Sweet Tatorman's picture

>Only joking an being a wise a$$.<
Wise a$$ or not, I'll use your question as an intro to the story of how Sweet Tatorman became a "prepper".
Something much more important to the Tatorman than sweetpotatoes is starting the day with the best possible coffee. The Tatorman will drink Bud Light, has even been known to drink "Two Buck Chuck" wine, but with coffee only the very best will do. To this end I have been doing my own roasting for many years using the best available green coffee beans. I only grind minutes before using in a quality consumer grade electric grinder.
Over a decade ago I had a power outage in the afternoon that persisted into the evening. By nightfall a sense of dread overcame me realizing I would have no means to grind coffee in the morning should the power still be out. By bedtime I had a plan of action. As luck would have it, I had recently been given a tour at my request by the owner/operator of a commercial chicken operation. I noted the presence of four standby diesel-generators. With a commercial chicken operation if you don't have power in the heat of the Summer you will shortly be dealing with 100's of thousands of festering dead chickens. The plan was to head over there in the morning with grinder and coffee. It turned out that the power was back on in the morning so this was not necessary. Traumatized by the near miss, I resolved to get a quality hand grinder. It turns out that post WW2 but pre German reunification there were many German ones made. I quickly acquired one but seem to have been unable to stop at just one. Like you and your 3 Kee mowers, I could not resist the allure of high utility at a low cost.

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Alacrates's picture

Wow, that is a great idea - it is amazing how much more durable & straight-forward some of these commercial machines are compared to what is on offer in the world of consumer appliances!

I'm curious, if you are always making your own cornmeal, what kind of kernels do use and where do you get them? Does it look like a big sack of popcorn kernels, or more like dried corn-on-the-cob kernels? What amount of dried corn do you keep before grinding it?

Sweet Tatorman's picture

I grow my own. Typically I harvest in the range of 40 to 60 kg per year and consume and give away somewhat less so tend to run a couple of years backlog on hand, probably 100 kg or so at the moment. The two varieties I grow which seem to do the best for me are Boone County White and Hickory King. These are both white open pollenated varieties dating from the 19th century. I have been growing from saved seed for a number of years and despite less than optimum isolation of the two types have so far managed to keep my saved seed true to type as near as I can tell.
Since you are skilled in the culinary arts I'll comment on the differences in characteristics of cornmeal ground from whole kernels vs store bought cornmeal. Whole grain corn is about 10% fat content calorically. Once ground the oils in the corn are exposed to oxygen which promotes going rancid. For this reason in the case of commercially produced cornmeal there is a milling step on the front end that removes the portion of the kernel that contains most of the fat. Unfortunately this step also removes some of the other useful nutrients. In my case it is usually about 10 minutes from grinder to oven so oil going rancid is not an issue. Refrigerated whole grain cornmeal is fine for a couple of months and even longer if frozen. Most cornbread recipes include some amount of added fat usually a vegetable oil or bacon fat. With the fat content retained in whole grain cornmeal I omit adding any fat at all to my cornbread. One other comment on whole grain cornmeal is that it has a lot more texture to it than the commercial stuff; somewhat "gritty" but in a good sense.
For an old post of mine that discusses growing corn for cornmeal see link below. This is from the old site but is still accessible. I don't think David has migrated this thread to the new forum site as I could not locate it with the search function.
Picture attached below.

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Alacrates's picture

Thanks for details Tatorman. Seed saving, corn growing, grain grinding, burr sharpening - this is some serious green wizardry! I appreciated hearing about it.

No restaurant that I've worked in ever ground their own flours/meals. I was aware of the problem of grains and flours going rancid after a certain period of time, but I'd never considered that fresh ground flours/meals that still have those often-removed outer layers would have different properties for cooking, I guess it only stands to reason though. I would bet that keeping all the parts of the grain would be the healthiest way, makes me wish that there were local shops that would grind a certain amount the grains on the day you were going to cook/bake with them, and I'm sure there are shops like that in many places.

I'll really have to try to get more involved with growing food. Just the way my life has worked out so far, working in kitchens for a long time until I switched to plumbing about 6 years ago, apartment living has always been my default, though I've helped out a bit in family members gardens, and had plots in community gardens as well.

One last question, just curious as to how you dry the corn for storage? Is there a shelf life on the dried kernels, or do you use it up before that ever becomes an issue?

Sweet Tatorman's picture

Shelf life of whole kernel corn is dependent upon % moisture content and storage temperature. A rough "rule of thumb" is that for each 1% reduction in moisture content or 10F reduction in storage temperature the shelf life will double. End of life is somewhat arbitrary. I can report that I have done a couple of blind taste tests of cornbread made from corn of different ages. With 11% moisture content and storage at 70-75F I cannot distinguish between 1 and 2 year old corn. With 1 and 3 year old corn I can distinguish between them but not in a way that favors the taste attributes of one over the other. Storage is in one gallon plastic milk jugs where I have coated the lip of the opening with Vaseline to ensure a good seal of the cap. If the corn is exposed to the ambient air it will eventually absorb moisture from the air until it reaches an equilibrium moisture content which is determined by the temperature and %RH of the air. Typically this will be at a value not conducive to long term storage.
In drying I typically target 12% or less moisture content. This is a multistep process. With favorable weather conditions initial drying is in the field reaching %MC in the range of 20-25%. After harvest but still on the cob the corn is further dried in a 1/2" mesh hardware cloth enclosure on a covered porch. Under favorable conditions a %MC of 15-16% can be reached which is still too high for long term storage but could likely make it through the Winter at reasonably low temperatures. At this point I hand shell the kernels from the cobs and winnow out the trash with the aid of a fan. To dry down to the desired final value I use an electrically heated drier with forced air constructed from a 30 gallon plastic bin, a small fan of the type used to cool a desktop computer housing, and a small <100W heating element. Air flow is from the bottom of the grain mass upwards. The air temperature and %RH at the top of the air mass is monitored. There are published tables of grain equilibrium %MC for various combinations of air temp and %RH.
Other than rodents, the other enemy of successful storage is insect infestation. This can be a tough one. Undetected insect eggs can be present at every step of the process. In addition to achieving as low a %MC as reasonably attainable the other thing that is mostly effective is to freeze the sealed containers for 1-2 days at 0F/-18C or lower. Even with these precautions I will lose a few jugs to infestation.

Blueberry's picture

Will post link to 2 places that we order wheat and oats from both give excellent service. I have never needed to order corn so can not give specific details about that product. Do not know if they ship to Canada.

Have no internet at home. Catching up at the library.

I am reading a fascinating book:

Grits: A Cultural and Culinary Journey Through the South
Erin Byers Murray

It's an entertaining history of ground corn, from ancient, indigenous people in Mexico to 21st. century farmers, millers, and foodies. It even covers nutritional deficiencies from eating over-processed corn (Eat hominy.)

Most fascinating so far: people who make a living as millers. There are a number of small companies that mill corn, rice, and specialty grains. Congaree Milling Company is a 2 man operation in Columbia, South Carolina. They have an "8-inch stone burr Meadows mill" set up in a "pizza and beer restaurant called Dano's". They make their own hominy onsite and roast their grains early in the morning in the pizza ovens. They mill a variety of heritage corn, sell it at farmers' markets, and supply restaurants in their area. It should be an inspiration for GWs. Other millers are grinding corn for small bourbon distillers.

There's a brief history of milling operations in early America and a contemporary history of Meadows Mills, which produces milling equipment. Since EVERYTHING is on Facebook somewhere, I went searching for Meadow Mills on FB and found a group Grist Enthusiasts, who search out old mills online, at sales, and in antique stores, then rebuild, repair, and trade them. And post pictures, of course. The book covers everything from "Political Grits" to cultural appropriation of native food. It's worth a read.