Found info on it years ago, was reminded a few days ago, and it's still up online, can be used for regular potatoes too: HOW TO MAKE SWEET POTATO FLOUR There are several grades of this product and quite as many ways to manufacture them. Each one of these flours or meals (as most millers insist upon calling them) has a particular character of its own and is therefore, adapted to certain uses the other products are not. These sweet potato flours are generally speaking of three kinds. First: Those made from the uncooked potato. Second: Those made from the cooked potato. Third: Those made from a careful system of roasting, or from the starch making process. The first two will interest the housewife most so, therefore, I will dwell almost or quite exclusively on these. FLOUR No. 1. FROM THE RAW POTATO Here, all that is necessary is to wash, peel and slice the potatoes real thin, dry in the sun, oven or dryer until the pieces are quite brittle, grind very fine in a clean coffee mill, spice mill, or any type of mill that will make wheat flour or corn meal; bolt through fine cloth in the same way as for other flours. The fine flour-like particles will pass through and the coarse granular meal left on the bolting cloths. USES This kind of flour is fine for making mock rye bread, ginger snaps, wafers, waffles, battercakes, custards, pies, etc. Bread can be made with it, but it makes a dough deficient in elasticity, bread dark in color and a loaf which dries out quickly. The coarser meals can be cooked in a. great variety of ways and make very palatable dishes, they Are to be soaked in warm liquid (whatever is desired. to cook them in) when soft, proceed as for grated potatoes. FLOUR No. 2. FROM COOKED POTATOES For the making of this flour the potatoes are broiled, or steamed (preferably the latter) until done, sliced or granulated by mashing or running through a food chopper and dried until they become very brittle, they are made into flour and meal exactly the same as given for Flour No. 1. USES This kind of flour is especially fine for bread, cakes, pies, puddings, sauce, gravies, custards, etc. Indeed, most people consider a loaf made in the proportion of one-third sweet potato flour to two-thirds wheat flour, superior in flavor and appearance to all wheat flour. Many experiments have proven that either the mashed sweet potato or the sweet potato flour may be used in bread up to as high as 50%, but at this point it becomes decidedly potato-like in texture and flavor but not unplatable or unwholesome. FLOUR No. 3. FROM PULP The sugar and starch has been greatly reduced. This flour is made from the pulp after the starch has been removed, it is dried without cooking, ground and bolted exactly the same as recommended for the other flours. When made into puddings, pies, blanc mange, etc., the same as shredded coconut, it resembles it very much in taste and texture and is very palatable, and is a most welcome addition to the dietary. It can also be used in the baking of bread and is especially valuable where people object to a loaf with the least bit of a sweet taste, also where they wish one with as little starch and sugar as possible. SWEET POTATO STARCH HOUSEHOLD METHOD This is very easily made, all that is necessary is to grate the potato, the finer the better, put into a cheese cloth or thin muslin bag and dip up and down, in a vessel of water, squeezing occasionally, continue washing as long as the washings are very milky. Allow it to settle five or six hours or until the water becomes clear, pour off; rewash the starch, which will be in the bottom of the vessel, stir up well, allow to settle again, pour off the water and let dry, keep the same as any ordinary starch. USES Use exactly the same as cornstarch in cooking; I am confident you will find it superior to cornstarch; it makes a very fine quality of library paste, and has very powerful adhesive qualities. In certain arts and trades it is almost indispensable. SWEET POTATO SUGAR By saving the water which the pulp was washed in first, in the starch making process and boiling down, the same as for any syrup, a very palatable, non-crystalline sugar will be the result; this sugar or syrup can be used in many ways. Here in the South and other sections of the country where fresh sweet potatoes can be had almost or quite the year round, the flour is not a necessity for bread-making; but for commercial purposes there are almost unlimited possibilities, and is destined to become more popular as fast as the public finds out what a delicious, appetizing and wholesome product these flours are. Our method of using follows with the hope that thousands of housewives will try out this most satisfactory way to add something new, wholesome, attractive and economical to the menu. HOUSEHOLD RECIPES SWEET POTATO BREAD Take: 1 cup finely mashed sweet potatoes 2 tablespoons warm water 1/2 yeast cake 1 teaspoon salt Two and 3/4cups flour, or sufficient to make a soft dough. Add the salt to the potatoes, and the yeast; pour in the water; add flour enough to make a smooth sponge (about a cupful); cover and set in a warm place to rise. When light add the remainder of the flour or whatever is needed to make a smooth elastic dough. Cover and let rise until light; mould; shape into loaves or rolls; let rise and bake. Many variations of the above bread can be made by adding sugar, butter, lard, nuts, spices, etc. SWEET POTATO BISCUITS Take: 1/2 cupful mashed sweet potatoes 1/2 teaspoon salt 1 cupful flour 4 teaspoons baking powder 2 tablespoons butter or lard Milk sufficient to make a soft dough. Sift the flour , salt and baking powder together several times; add these to the potatoes, mixing in with a knife. Now work the fat into the mixture lightly; add the milk; work quickly and lightly until a soft dough is formed; turn out on a floured board; pat and roll out lightly until about one-half inch thick; cut into biscuits; place on buttered or greased pans, and bake twelve or fifteen minutes in a quick oven. SWEET POTATO BISCUITS No. 2 (EXTRA FINE) Take: 1 cup boiled and finely mashed sweet potatoes 2 eggs, well beaten 2 cups flour 2 teaspoons baking powder 1 teaspoon salt 2 scant tablespoons melted butter or lard 1 tablespoon sugar (if desired) 2 cups milk. Mix together all the dry ingredients and stir into the milk, beaten eggs and potato. If too soft, add more flour, sufficient to make a soft dough. Roll out lightly; cut with a biscuit cutter; bake in a quick oven. SWEET POTATO BREAD (BAKER'S METHOD) This recipe was given me by Mr. J. M. Colter, who had charge of the Institute's Bakery. Take. 70 pounds of wheat flour 30 pounds of finely mashed sweet potatoes 40 pounds of water 1 1/2pounds of salt 1 pound of sugar 1 pound of lard 1 pound of compressed yeast. Every other operation is exactly the same as for bread or rolls made from all wheat flour. Mr. W. T. Shehee, former steward of the Boarding Department, says it not only gives universal satisfaction, but is preferred by many to bread or rolls made from all wheat flour. I have very briefly and imperfectly touched upon the many possibilities of the sweet potato. I trust that Macon County will take the lead in developing the almost limitless possibilities of this splendid crop and show its relation to the dairy industry, beef production, starch mills and that it is the most important and useful of all our root crops for the feeding of farms animals. by Tammy Moore posted under Celiac “How to Make Your Own Potato Flour – Lessons from George Carver”
Great information! Would never have thought about this and have an abundant supply of sweet potatoes each year. Thanks
Great ideas for SHTF options for chrone's and Coeliacs An excellent post and link.......this will be a wonderful option for folks with Coeliac or Chrone's disease, and for people who are gluten intolerant. The hint on producing sugars from sweet potatoes will be good in hard times when cheap milled sugars from sugar beets or cane sugar may not be readily available. BRAVO!
Glad you all like it. Oh speaking of sugar beets, Bountiful Gardens has nonGMO sugar beet seeds for sale(in the catalog they're called white beets). I was gonna buy some this month, but when I went into town on payday(aka bill-pay-day), came back with an almond tree, 3 chicks, and a blueberry plant/bush.