Little does the average housewife, who makes her bread by old and approved ways, dream that there is held every day of the year a school for bread inspec tion and that it is largely due to the "school" that, her bread baked in her own oven is so good. In the "Flour City" of Minneapolis are the largest flour mills in the world, and here all day long and all night long is ground flour that is shipped to China, India, and all parts of the world. It is here that the "bread school" is held, and a most interesting day can be spent in attending this same school and watching the bakers and millers. Every barrel or sack of flour that is sent out is tested, not once but many times. ar.d the "bread school'1 is part of the test. So minutely are the records of these experiments kept that if a letter came from Bombay saying that a car load of flour was found de fective on its arrival, it is possible by looking over the register and tracing its course from its entrance as grain to the finished prod uct, to know what condi tion the flour was in when it left and whether it was injured in shipment iron dampness or other causes. Think of keeping track of nine million barrels of flour! And yet this is the output of one company alone a year. Every large mill has a kitchen, and in this takes place the final test to which the flour is sub jected. Before it reaches this kitchen the wheat has been through many processes and experiments, but it is the kitchen trial that stands as the ultimate cri terion. When the hard spring wheat of the Red River Val ley of the North, which contains more phosphates and gluten than any other wheat in the world, is ripe, it is shipped to numerous small country elevators in Minnesota and the Dakotas, where it is stored tempo rarily, ready to be sent to the big grinding mills. Sometimes this wheat is grown by small farmers, but more often it is the product of very large ranches. Here acres and acres of wheat as far as the eye can reach are nodding in the wind, so that it looks like a sea of grain before it is cut. When it is gathered it is dumped into elevators owned by these ranchmen. Short railroads run to the elevators. When the wheat reaches the mills it is side-tracked and the cars are unloaded by means of huge automatic grain shovels. Inside of the mills the grain is at once submitted to a rigid gluten test to disclose its strength and the best is made into flour. The latest method for making flour is the reduction method ; that is, the wheat is granulated instead of pulverized. One hundred and fifty separations are made from the time the wheat is received until it is ready for shipment, and as all t his work is done by machinery, with clocklike precision, the rapidity with which flour is turned out is wonderful. To begin with, the wheat is sent to the roller mills, where it gets the first crush. From here it is carried to a sieve where the middlings or grits are separated. This is done with rollers, which are pressed together six times, each time closer than before, so that the middlings become very fine. The finest result of this sixfold crushing is put. through purifiers, where all imperfections are removed by suction and sifting. Dust and dirt are caught in a dust collector made of flannel tubes, and the middlings are then ready to be ground into flour. Not the least marvelous part of this preparation is the machinery with which the work is done. Auto matic carriers elevate and transport the grain in all directions, and the visitor is lost in amazement at the precision and ingenuity. Even the exact amount of flour which is finally dropped into barrels or bags is ascertained b y m a c h i nery, so that no more and no less than the desired quantity falls down the spout into the re ceiving recepta cle. This receiv-i ? g receptacle, whether bag or barrel, is usually marked to indi cate the brand of the flour. Every one has seen the mark XXX and XXXX and won dered what it m e a ? s, but this is simply the mark which indi cates the ex cellence of the flour. At cer tain stages dur ing its prepa ration the mid dlings are sent to the mill's chemist to be tested, and be fore it reaches its last resting place ready for shipment it is the chief ob ject, of interest in the kitchen. This kitchen is a series of well lighted and ventilated rooms. The walls are of spotless white, the pans shining, the ovens are electric and of the most approved pattern with glass doors, thermometers, and every other convenience for baking bread in the latest and best way. The housewife would be delight ed with these kitchens. All day the chemist and bakers work in these rooms. First they make the gluten test, where the half-ground wheat is mixed with water into little pats that look exactly like the children's mud pies. These pats are allowed to stand on glass for a certain length of time, and their con sistency at the end of that time determines the grade of the wheat. A record is .taken of this by the chem ist in his big book, and the carload of wheat of which this is a sample is kept track of during all its pro cesses. This makes it possible to turn to the many hundred bottles on the chemist's shelves and to find the sample and see exactly how it ranks by chemical analysis. The report of the gluten and other tests made during the grinding of the wheat is sent back to the head miller who is handling it, and he in this way knows what, quality he is dealing with. Of course every day a certain number of barrels of finished flour is turned out. The largest mill in the world turns out 15,000 a day, and some companies run several mills. Think what a tremendous undertaking it is to keep track of the quality of that, amount of flour! Yet this is done. Every morning, before nine, the head millers send to the kitchen samples of the finished flour which they have waiting for barrels. After the flour is marked so that the chemist knows which miller sent it and it is compared with the tests which he has made during its preparation, the cook, in white apron and cap, begins to mix his bread. He makes his own yeast that he may be sure of the qual ity, and he has many small jars. Enough flour for one loaf of bread is put in each jar and care is taken not to mix the flour, as in this case there could be no test. After the bread is mixed, one loaf in each jar, and as many jars as there are brands of flour, it is allowed to rise and is finally baked in the electric oven. An immense row of these ovens stretches across one side of the room, one above the other. Great care is taken in the baking, and electricity is used in preference to other heat that the temperature of the oven may be the same all over. In ovens heated by other methods the bottom is hotter than the sides or top. When the bread is finally done it is placed on a long wooden table to cool. Every loaf is the same size and shape, for the same amount, of flour was used in each, and they look alike, but the wily chemist has kept, track of them in his book and knows, exactly what flour was used in each and what mill it came from. At four in the afternoon the bread is cool and the chemist proceeds to cut each loaf in two, using a tape line so that the measurements will be correct. Then he sends for the head millers. In they file, and stand in solemn silence around the half loaves of bread until the chemist asks them to inspect it. Every half loaf is taken by the millers, held in the hand to weigh it, punched to see how flexible it is, taken to the window to examine the grain, and the pores are carefully noted. Then each miller tells which he thinks is the best loaf and the loaves are graded accordingly. No man knows which loaf was made from the flour sent, from his mill. The chemist compares his notes with the decision of the millers and thus knows exactly how these particular ship ments ought to be branded. The final test is this by the millers. It cannot but. be impartial, and is the best means of telling how the flour ranks. Altogether the school of bread inspection is the most interestii.g of any of the- proceedings in the large mills, and hours could be spent, watching the process of making a barrel of flour.
This article was originally published with the title "A Curious Bread School" in Scientific American 97, 20, 364 (November 1907)