Tuesday, May 11, 2010

How Does Flour Come From The Farm?

I found this in my referral logs, and me being me, first thought of a smartass answer.

Flour couldn't make it into the grocery store without the help of the Flour Wizard. He and his little helpers (Local #112 of the International Order of Skilled Elf Laborers) slip into our fields at night and transform the raw flour nodules into a huge cloud of flour, which is transported through the air by magic and deposited in the back rooms of grocery stores everywhere, bagged and ready for sale.

But, that isn't fair or nice, because some people have no clue about the mechanics, markets and processes necessary for flour to arrive at their stores. As a farm kid and someone who gets a small benefit from farming, it behooves me to answer that question as best I can. So, without writing the long treatise about the subject that it deserves, here goes.

Flour is made from a variety of grains, most commonly wheat. Rye flour, from the small grain rye, is used to make the rye bread in your Reuben Sandwich. So, for sake of brevity, we'll say that flour is made from cereal grains, which include wheat, which is what I'm most familiar with and will (marginally) cover here.

First, there are several distinct varieties of wheat grown on the Great Plains:
  • Durum — Very hard, translucent, light colored grain used to make semolina flour for pasta.
  • Hard Red Spring — Hard, brownish, high protein wheat used for bread and hard baked goods. Bread Flour and high gluten flours are commonly made from hard red spring wheat. It is primarily traded at the Minneapolis Grain Exchange.
  • Hard Red Winter — Hard, brownish, mellow high protein wheat used for bread, hard baked goods and as an adjunct in other flours to increase protein in pastry flour for pie crusts. Some brands of unbleached all-purpose flours are commonly made from hard red winter wheat alone. It is primarily traded by the Kansas City Board of Trade. One variety is known as "turkey red wheat", and was brought to Kansas by Mennonite immigrants from Russia.[17]
  • Soft Red Winter — Soft, low protein wheat used for cakes, pie crusts, biscuits, and muffins. Cake flour, pastry flour, and some self-rising flours with baking powder and salt added for example, are made from soft red winter wheat. It is primarily traded by the Chicago Board of Trade.
  • Hard White — Hard, light colored, opaque, chalky, medium protein wheat planted in dry, temperate areas. Used for bread and brewing.
  • Soft White — Soft, light colored, very low protein wheat grown in temperate moist areas. Used for pie crusts and pastry. Pastry flour, for example, is sometimes made from soft white winter wheat. From Wikipedia
These varieties have different moisture and growing season requirements. Winter wheat is grown in my area - it is planted in the fall, and lies dormant in the winter. When spring warms the ground enough, it begins to grow again and (hopefully) grows to maturity, harvesting in the summer. The growing seasons for wheat in the northern Great Plains are much shorter as well and have harsher winters, so spring wheat is grown there. It is planted in the spring and then harvested that summer.

It should also be noted that corn (maize) is also a cereal grain, but I'm gonna concentrate on the wheat varieties. Dent corn isn't really suitable for human consumption - it's livestock feed. Sweet corn isn't grown for industrial flour production, either. Other feed varieties of maize are also grown for feed as well. Milo (or sorghum) - normally a feed grain - is processed into flour - there is a Grain Products, Inc. mill in Dodge City, KS that does just that. However, the flour is used for making drywall. Not edible.

So, we've got wheat in our fields now, and somehow it has to be made into flour. First, it must be harvested, which is accomplished by mechanical means - known as combines. I've written about combines before - as a gearhead, I get a charge outta the big machines. Winter wheat varieties are generally processed by a combine with an attached small grain header, cutting the wheat and separating in one operation. Spring wheat is usually swathed - cut into windrows and after the straw has "dried down" combines with a pickup attachment instead of a full blown small grain header run along the windrows and separate the wheat, also known as "threshing." The grains are separated from the heads and captured in a storage tank in the combine. The rest of the plant (straw and chaff) goes out the rear of the combine, to be recycled back into the soil.

So, now we have the wheat out of the plant and into the combine. Generally the combines are accompanied by a "grain cart," which is a large self emptying container for grains that is towed by a tractor. The grain carts usually pull next to the combine while it is threshing, the combine extends it's unloading auger over the cart, and the combine empties it's grain bin into the cart. When the grain cart is full, it drives to a truck (parked on hopefully solid ground, safely away from any mud) and unloads on it. This saves the combine from having to stop threshing, and gives the combines a place to unload when the trucks are on the road.

In this shot, the combine is unloading into the cart, which is unloading into a truck. It's probably because the field is done, and all the grain from this field has to be kept separate from the next, or it might be lunch or dinner time.

Now we have the grain in a truck, ready to go. But where? Sometimes the farmer has storage bins on his farm, and the trucks go there. When he sells the wheat, it has to be hauled to the buyer, which is usually a grain company. Sometimes, there are local flour mills, but usually, the farmer has to market his grain to a company dedicated to handling large amounts of commodities. Most terminal destinations involve an elevator. Many grain elevators are owned by cooperatives, or Co-ops. We'll send this truck to the local elevator, then.

Most elevators or grain terminals have access to transportation more suited for bulk shipping than trucks - think railroads or barges on rivers or ports. Ports are for export, which isn't putting flour on your table, but railroads do ship to flour mills. Most grain semis haul around 900 bushels of wheat (legally), but rail hopper bottoms are generally about 3300 bushels capacity. When a grain company markets wheat to be shipped by rail, they use a contract that stipulates certain parameters of quality for the wheat. It must have a minimum protein content, only contain a certain percentage of waste, fall within a certain moisture content percentage range, be pest and mold free, have a minimum "test weight" and other factors. Each car is "probed" or has a sample removed and inspected by the grain division of the USDA. Then, the whole car is "certified" to be of an assured quality. Unless the inspectors find bugs, or low protein, or whatever.

The grain merchants and local co-ops are well aware of the necessary standards, so they often offer a premium for higher quality grain they receive during harvest or when a farmer hauls his crop in during the winter. If everything goes well, a farmer might get a few cents per bushel premium over what the local market price is at the time.

Another little tidbit - pricing for hard red winter wheat in this area is based on what the Kansas City Board of Trade is offering that day, minus the freight charges to get it there. If the local feedlots are feeding wheat, the local coop might offer more than the "KC" price is at the time. It's a very fluid situation - the futures market plays a major role in day to day pricing as well.

So, now we have the wheat at a flour mill. The above picture illustrates the three parts of a kernel of wheat. The bran is the protective outer coating, the germ is the part of the seed that would start a new wheat plant, and the endosperm is food for the germ. It's also what white flour is made of. The wheat kernels are ground up with steel wheels, and the germ and kernel are separated. Historically, flour had a very short shelf life when there was no way to separate the various parts, because the fatty content of the germ would go rancid and cause the flour to go sour. So, it wasn't evil capitalists that just decided one day that the fiber (and associated vitamins and minerals) was just too healthy for the teeming masses and just had to be taken out - it was the technology of the time making a necessary food staple last far longer in a useful condition. Now, the bran and germ can be heat treated and returned to the mix for longer storage times for bran flour. Some modern mills use stone wheels for grinding whole bran "stone ground" flour.

In the instances where the germ and bran are not returned - it doesn't go to waste. They are known as "wheat middlings" and are used as an ingredient in livestock feed.

So, now we have the flour at the mill. Some ship the flour out by bulk - truck or rail - in pneumatic trailers or cars. Most at least have the ability to bag the flour, and some reduce it to consumer sized units. A pretzel factory wouldn't want to buy flour by the pound bag - they're gonna want it by the truckload or rail car. A local bakery is going to want their flour in large bags shipped on pallets - they might only need one hundred pound bag a day, for instance. At any rate, not all the millers bag flour directly for the consumer. Many are set up for industrial customers only.

Now, we've got flour in a one pound bag at a mill. They'll box it up with a certain amount of bags per box and palletize the boxes. Then it is shipped to a grocery distribution center, where the pallet is broken down back to the boxes. A box of one pound bags is then shipped to your grocery store, where your neighbor's kid works, who will cut open the box and stock the shelf. Then, hopefully, you'll buy that paper sack full of flour, taking it home to feed your family.

That is how flour comes from the farm - in very simple and abbreviated terms.


drjim said...

I kind of knew some of this process, but not all of it. Thanks for explaining it.
When the combine returns the straw and chaff to the field, does it just lay there, or is there another step to plow it back under? Coming from Illinois, all I know is corn and soybeans! I remember the farmers in my area always leaving a few rows of corn standing to feed the deer and pheasants during the winter. I always thought that was right neighborly of them.

Jeffro said...

That's one of the problems with not going into really good detail in a post like this - I had to drop a lot to keep it shorter than War and Peace.

There are several strategies for the straw. The SOP is for the combine to be equipped with a straw spreader (think windmill wheels with belting instead of metal blades) at the rear - as the straw and chaff hit it, it spreads the straw over an area approximating the width of the headers, making the spread even. On summer fallow ground, this is part of the ground cover to prevent wind and water erosion. When the ground gets weedy, a sweep plow is used to undercut the weeds and leave the trash on top. The trash will naturally deteriorate during the fallow time, and if the refuse is really heavy, it may be worked with a double offset disk plow to put the trash "under" and facilitate it's breaking down. The double offset leaves far more trash on the surface than a moldboard plow would, which is why it's used in the old Dust Bowl areas today.

If the ground is irrigated and needs to be worked right away for replanting, the combines might have a straw chopper mounted that really processes the refuse. It is worked under with a double offset almost right away.

Sometimes the farmer might want to save the straw for use as filler feed for cattle. The cheap way was just to disconnect the straw spreader keeping it in a loose, long pile and follow up with a rake to make it easier to pick up with a baler. The new high tech way is to use a stripper header, made by Shelbourne, that just strips the heads from the plant, leaving the straw intact. This is also considered good for the combine, as it doesn't have to process as much plant matter. The straw can then be swathed and baled.

And, sometimes the straw is burned - something my father was adamantly against. Burning takes a lot of nutrients out of the soil, besides the danger of fire on the prairie. But sometimes there just isn't enough time to work it under and not have it too trashy to plant again. A drill with the close spacing wheat requires can be clogged very easily by even a small amount of surface plant residue.

Then there is no till, which I really don't know much about. I think there are solutions that are sprayed on to help break down the straw that can be applied with herbicides and fertilizer.

And lots of guys leave a strip of corn or milo for the game to eat. We do that with the fall crops - wheat wouldn't stand that long and be of any feed value by winter. It's really a pretty fragile plant.

drjim said...

Ahhh....didn't know wheat was fragile like that. Guess it would just rot, and not be good feed for the critters. I *do* remember seeing the "diskers" in the fields right after they were harvested. Guess that was for turning under the stuff, but I never knew that's what they used. I always thought the "diskers" were just for breaking up big chunks and kind of grinding up roots and stuff, but now I see how they'd work the things back into the soil.
I went to Joliet Junior College, which at the time was considered a "feeder school" for the U of I down in Champaign-Urbana, which had quite a good College of Agriculture at the time. I think some of my classmates also went on to Texas A&M.
Used to really piss me off when the "city kids" would make fun of the "farm kids", but the "farm kids" always seemed to get better grades, and get accepted to the Colleges they applied to much more often that the "city kids", who just wanted to hang around the Student Union building, cutting classes and playing cards!

Jeffro said...

Wheat's fragility is why we are deathly afraid of high winds, heavy rains and hail - normal thunderstorm effects - just before harvest. The grain can be knocked out of the head so easily, and the straw snapped, putting the heads on the ground below the reach of a combine header cutting bar.

I knew some sisters from Florida who refused to eat fresh green beans from a friend's garden because they were too "dirty" - they actually saw the garden. From a can? That was normal, ok, and clean to them. I still laugh when I'm reminded of those two. Damn good looking, but not too much going on upstairs.

drjim said...

Oh, man, that's a HOOT!
They probably go vegan if they ever saw a feedlot!