Updated: Apr 20, 2021
Several weeks ago, we followed corn through the mill as it became cornmeal and
finally was bagged for sale. Today we’re going to follow a much different route as cereal
grains (wheat, barley and buckwheat) are ground into flour. Buckwheat, despite the name, is not a wheat at all, it’s not even a grass. It's actually related to sorrel and knotweed and is referred to as a pseudo cereal.
Up until the end of the 19th century the grain milling process was quite similar to the corn process. They were both milled with millstones and at our mill most people wouldn’t be able to tell what the differences in the process were. But in the late 1800s the mill was updated to a new “Roller Milling” system and quite lot of new equipment was installed, plus numerous grain and flour bins and the related elevators and chutes necessary to move the product from one area to another.
This would have been a huge, but necessary, investment for the miller brought on by the public’s demand for very fine, “pure.” white flour. As soon as one mill in an area started producing roller-milled white flour, all other mills were forced to follow suit in order to stay competitive. The strange thing is; this “pure” white flour was much less nutritious than the whole wheat flour the mills had been producing and eventually millers had to “enrich” their flour with added vitamins and minerals.
So, How did the Roller Milling process work?
At Ainsworth Abbott’s mill, bags of grain were off-loaded from wagons or trucks onto the dock in front of the mill.
It was brought in the door, weighed and
then dumped down a chute (#1) into a bin in the basement. The bin slowly metered the grain into the bottom of a large elevator that carried it all the way to the receiving separator (#2) in a tiny space in the attic dormer that overlooks the millpond.
Here it was cleaned of any weed seeds, dirt and debris and it then fell down a chute to any of several grain bins. The seeds and debris fell down another chute to be bagged in the receiving area, weighed and deducted from the weight of the grain.
On the second floor there are several large bins for Wheat, Barley and Buckwheat, as well as cleaned Wheat that would be sold in the spring as seed for the new crops. A couple of the bins might be as large as your bathroom at home.
Mr. Abbott would then open a gate on the proper chute to allow the grain to slide down to the scourer and polisher, a small machine that tumbles the grain in a metal drum to remove impurities that may adhere to the skin of wheat, things like dust, dirt and smut (a type of fungi).
As with all other machines in the mill, when the product left the scourer it fell through a hole in the floor and went to the bottom of a different elevator in the basement. It always went to a different elevator.
#3 Scourer, #4 Sieve “Gyrator” Bolter, #5 Flour bin, #6 Flour Packer, #7 Flour Dresser
The elevator carried the grain up to the attic where it fell down to a small holding bin above the roller mills.
When actually ready to begin milling Mr. Abbott opened another chute gate to allow the grain to fall down to a series of six roller mills.
Just before it reached the first mill the grain passed by five magnets sticking into the chute, just in case there was some type of ferrous metal mixed in with the grain.
There are essentially only two things that happen in this milling process, grinding and separating and the process is referred to as a gradual reduction.
The wheat kernel (endosperm) is gradually reduced in particle size by running it between a series of rotating hardened steel rollers, either corrugated or smooth. All pairs of rollers in a mill have one slow roller and one fast one. The rollers turn in opposite directions, toward each other, pulling the stock (material being ground) between them. This gradually tears the kernel apart, rather than crushing it.
Each time the material leaves one of the roller mills it falls through a hole in the floor and enters another elevator in the basement to be taken all the way up to the attic and back down to the gyrating sieve on the second floor. In the Gyrator the "overs" (bran, germ, shorts, or red dog) are slowly separated from the endosperm, which then goes down to the next roller mill to be reduced in size slightly more. In this mill the process repeats up to 6 times.
After traveling through all 6 pairs of rollers and the gyrating sieves, the flour is directed to one of two flour bins, while the “overs” are directed to the Flour Dresser in the attic.
In the dresser the material enters a sloping, silk lined rotating cylinder. Any remaining flour goes through the silk, while the “overs” make their way to a separate bin on the ground floor for animal feedstock. Adapted from ‘The Milling Process’ by Thom Leonard)
One of the two flour bins is for local sales. If you lived in the neighborhood and wanted to bake some bread, you could send one of your kids (or all of them) down to the mill to purchase a bag of flour. Mr. Abbott would open up the bin, scoop up some fresh ground flour and fill a brown paper bag for you. Can you imagine what that fresh-baked bread must have smelled and tasted like? Mmmmmmmm good!
The other flour bin above the "Pearl" Flour Packer was for commercial sales. Mr. Abbott put an empty flour barrel on the platform and then spun a wheel that raised the platform up and also turned on the flow of flour. Inside, an auger in the large vertical tube packed the flour into the barrel. When the barrel reached a pre-determined weight, (about 195 lbs.) the machine automatically shut off the flow of flour so that Mr. Abbott could remove the barrel and put on another empty one. While this one was filling, he could put a lid of the first one and position another empty barrel ready to be filled. During this entire filling process, he didn’t have to move from this one spot. The packer could also be used for filling sacks of flour. Mr. Abbott sold his flour in country stores from Dover to Georgetown.
This entire process was all thanks to whom? Delaware's own Oliver Evans, of course.
If you haven't heard of Oliver Evans, please see my Jan. 17th post;
“Who was Oliver Evans.”
And if you would like to hear more about milling and Oliver Evans, I'll be giving a public talk about him on this coming Thursday, April 22nd starting at 7:30. This is part of a FREE Spring Speaker series put on by Old Wye Mill. You can click on this link to get signed up: https://www.eventbrite.com/e/owm-spring-speaker-series-tickets-146750734397
Just a reminder that Abbott's Mill will be open for tours this Saturday, April 17th. Fortyfive minute tours start at 1:00, 2:00 and 3:00 and are free to Delaware Nature Society members, $5 for all others (no charge for children under 10, accompanied by an adult.) There is a limit of 6 persons per tour for now, with masks, so please pre-register to make sure you have a spot: 302-422-0847 and ask for Matt. I hope to see you