Till' FARMER'S MAGAZINE, 



491 



PRESERVATION OF GRAIN FOR FOOD. 



In the number of this magazine for October, 1856, 

 and in following numbers, we presented a few remarks 

 on the important subject of drying of grain in the bulk. 

 We now propose to glance at those projects which have 

 for their aim the preservation of the grain after separa- 

 tion from the straw. Our remarks in connection with 

 this subject will be confined chiefly to wheat, that being 

 the most important of the cereals with relation to the 

 food of man, as yielding the largest per-centage of flour 

 in grinding, the loss being only one-fourteenth, while 

 that of oats approaches nearly to one-half, barley coming 

 closer to the standard of wheat, giving nearly six -sevenths 

 of its weight in flour. 



That which chiefly influences the preservative power 

 of wheat is the amount of water or moisture it contains. 

 Containing from 12, 14, 16, and in some cases 20 per 

 cent, of moisture, it is in this condition liable to decom- 

 position ; and it is only when the per-cent.-.ge of moisture 

 is 1 educed to 8 and 10 per cent, that its keeping in good 

 condition can be secured. In certain parts of the conti- 

 nent, where this moisture is greatly reduced in wheat by 

 careful ventilation and drying, it can be kept without 

 injury for lengthened periods, varying from seven to fifty 

 years. But not only is the preservative power of wheat 

 increased by careful drying : it greatly augments the 

 value of the flour obtained from it for bread making pur- 

 poses. *' It will yield," says a practical miller, " much 

 more flour per bushel, and require about half the machi- 

 nery to manufacture it, than it otherwise does if not 

 dried. The quality of the flour is improved at least 

 10 per cent., as by drying the wheat all impurities of a 

 vegetable nature are entirely removed ; and by extract- 

 ing its natural moisture, the flour will consume, when 

 baked, more water than it would before the grain was 

 dried, which makes the bread much more palatable, it 

 being more spongy." The higher, then, the per-centage 

 of moisture in grain, the more difficult is it to keep, and 

 the less valuable is the flour obtained from it. In a warm 

 climate — as that of the United States — in summer, the 

 addition of moisture to grain or flour has a tendency to 

 diminish the quantity of gluten, and to promote such a 

 change in the constitution of its parts as to prevent good 

 baking, or " panniKcation," as it is termed. An excess 

 of moisture also favours the production of sporules of 

 different kinds of mushrooms, these being developed in 

 the bread which is made from the flour so deteriorated. 

 Professor Dumas slates that the wheat of the year 1841, 

 remarkable for its warm summer, exhibited in a high 

 degree this defect. The bread in which these mushrooms 

 were developed was raised in temperature, and soon pre- 

 sented a mass of reddish and disgusting matter. By 

 thoroughly washing the infected grain, and following it 

 promp'ly by a desiccation or drying, the number of spo- 

 rules was much diminished. The development of the 

 mushrooms in the bread was, in some measure, pre- 

 vented by reducing the proportion of water, increasing 



the quantity of salt, and by increasing the temperature 

 of the oven in which the bread was baked. Seeing, then, 

 the chances of loss and deterioration of value which sur- 

 round Ihe farmer in the storing of his grain, it is ob- 

 viously a matter of no mean importance to investigate 

 those plans which have been proposed to preserve it in 

 a condition fitted to produce the largest amount of good 

 bread -producinsj; flour. 



The preser\ation of grain for food-purposes obviously 

 resolves itself into two processes : first, that which 

 gives the grain those qualities which retard or prevent 

 deciy ; and second, that which tends to preserve or 

 maintain those qualities. The two processes we there- 

 fore call the " p' eparative" and the " preservative." 



The main feature of the "preparative" process is the 

 getting rid of the excess of moisture. This drying, or 

 desiccation, as it is termed, may be effected in a vast 

 variety of ways. Perhaps the oldest of all the plans 

 requiring special arrangements — other than those in- 

 volved in the most ancient of all modes, spreading the 

 grain in the sun-heat — is that introduced by Dr. Ste- 

 phen Hales in 1743, and held in high repute, according 

 to cotemporary evidence, by the farmers of the time — a 

 curious instance, by the way, of the odd fate which meets 

 many inventions and processes, used to-day and obsolete 

 to-morrow ; and that not from better being introduced 

 to supersede them, but from the process which they are 

 designed to aid being quite ignored in succeeding prac- 

 tice. The method adopted by Dr. Stephen Hales was 

 blowing or forcing currents of air through the mass of 

 grain exposed to its influence. A tube perforated with 

 holes was inserted in the centre of the mass, into which 

 the air was blown, pouring through the apertures ami 

 permeating the material. The farmers of the day used a 

 modification of this plan by taking a reed or cano perfo- 

 rated with numerous holes throughout its length, placing 

 it in the centre of the grain retained in a sack, and 

 blowing, by means of a common bellows, quantities of 

 atmospheric air through it. In the " Gentleman's Ma- 

 gazine," a statement is given which shows that 

 the plan was in use in France. A member of the 

 Academy of Sciences, M. Hamel de Monceau, having 

 preserved a large heap of corn free from weevils for two 

 years without turning, by merely blowing air through it. 

 If we preserve the blowing feature, and substitute hot 

 air for that having the ordinary atmospheric temperature, 

 we increase the desiccating or drying properties, and 

 arrive at a process of recent invention, which assuredly 

 takes its place as one of the most efficient, if not the 

 most eflicient, of all plans for preserving vegetable sub- 

 stances. We allude to the desicci ting process patented 

 by Messrs. Robert Davison and William Symington, of 

 London. This plan may be briefly described. A series 

 of cast-iron pipes are arched over a furnace, through 

 which, by a powerful fan, a current of air is forced. The 

 high temperature of the pipes heats Ihe air. The mate- 



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