MALTING.
Many opinions are entertained as to the best mode of making malt; some persons being great advocates for sprinkling the corn with water during certain stages of the process upon the floors, while others maintain that nothing of the kind is necessary, but rather injurious. As this is not intended for a treatise on malting, we shall not enter into any discussion upon that subject; but shall merely observe, that the practice may be either necessary or not, according to circumstances. In some malt-houses we have found it absolutely necessary to sprinkle for promoting vegetation, while in others, differently constructed, nothing of the kind was required.
The Excise allows sufficient latitude for wetting any kind of barley; it must not, however, be less than forty hours under water. The general mode of ascertaining when barley has been sufficiently steeped for malting, is first by its increase in bulk as shown by the dipping rod. A practical maltster generally judges from the compressibility of the pickle when squeezed endways between the thumb and finger. When sufficiently steeped, and after the water has been discharged, the barley is thrown (or in some instances drops through a valve or socket) from the cistern into the couch, where it must by law be let remain undisturbed not less than twenty-six hours, but longer if thought necessary. It is then spread out upon the floor to a thickness greater or less, according to the season and temperature of the atmosphere, at the discretion of the maltster. The rootlets now begin to make their appearance, and great care must be taken to turn the corn occasionally, but gently, so as to prevent any of the fibres shooting out too long, or wiry, as it is technically called. A short bushy root is most desirable. But each variety of barley exhibits different lengths of rootlets. Thus the chevalier is very different from the common barley and the bigg.
No definite rules can be laid down as to how often the floor or piece of malt may require to be turned during the process; this must be left to the skill and judgment of the operator.
Although the law does not permit water to be sprinkled on the corn until after a certain period, when in our opinion it should be no longer necessary, yet the maltster is allowed to sprinkle water upon the bare floor before turning the corn either forward or backward, and this may often be found very beneficial.
Some maltsters have now adopted the thermometer as a sure guide during the process: whenever that instrument indicates an increase of temperature of so many degrees, the malt is turned. This, however, is not a certain criterion. The thermometer will be found a highly useful instrument to guide an inexperienced operator to a certain extent, but it should be used in conjunction with practical skill, else it may do as much harm as good. The humidity of the atmosphere over the malt should be taken into account. The thermometer only shows the temperature, a hygrometer (Daniel’s) would point out the moisture, &c. Quite as much injury is done by turning too often, as by repeating that operation too seldom. An experienced maltster is guided a great deal by the appearance and smell of the corn in process, and also by the increase of temperature. The common mode of judging is by thrusting the hand into any piece of malt, and taking from the bottom a sample. The state of the rootlets of this portion are then examined; if they are running wild, as it is technically termed, or one fibre be protruding far beyond the others—the corn should be turned—if any fœtid smell be perceptible, the same operation is necessary, and also a fresh current of atmospheric air to supply more nitrogen and oxygen to the malt. Mr. Rigg’s late publication states that a great deal of carbon must be given out during the germination of the malt. It has been already stated that short bushy rootlets are the best; the great desideratum, therefore, is to preserve these bushy rootlets, which can only be accomplished by proper care and judgment in turning the corn. The skill of the maltster may be always known by this criterion. Whenever the rootlets begin to appear the spire or acrospire begins to shoot up at the back of the pickle, and as it proceeds the barley is converted into malt. The nearer, therefore, that the spire can be brought to the far end of the pickle, without protruding beyond it, the more perfect will be the malt. About the fourteenth day, generally speaking, the malt should be ready to be brought to the kiln—previously, however, it should be gradually made mellow, by gathering it thicker on the floors, so as to come to a temperature of 75° or 80° F. The steep or any water which may have been applied during the process, should have been by this time pretty nearly evaporated, so that the malt may feel dry to the hand.
Drying Malt.
There are various opinions as to the best mode of drying malt, some adopting a long process, and others a process much shorter. If the kilns are properly constructed, and the malt be thoroughly made before being put upon the kiln, twenty-four hours, or perhaps less, will be found fully adequate for that purpose. The greater the quantity of heated air that can be thrown in during the process of drying, the more mellow will the malt be. The best constructed kilns, therefore, are those by which the greatest quantity of heated air can be most quickly introduced. If a great current of heated air be constantly directed through the malt on the kiln no danger of acquiring colour need be apprehended. This current of heated air, however, should be admitted through open apertures, running longitudinally along the furnace fire, on the outside of the Welch lumps of fire-bricks. If, on the contrary, colour should be wanted, it is only necessary, just before taking the malt off the kiln, that all currents of air should be shut off or prevented, excepting from below the bottom of the furnace; a quick fire having been previously made and kept up, any colour may be very speedily acquired. Care, however, must be taken, during this process, by frequently turning on the kiln, to prevent the malt being burnt.
There is a prevailing error, that malt should be frequently turned on the kiln during the process of drying. A little consideration, however, will show the inaccuracy of this opinion. It has been already stated, that when the proper currents of heated air are introduced in drying, no colouring of the malt need be apprehended. We know that the portion of the malt nearest the covering of the kiln sometimes feels quite dry, while that on the top is quite damp; if, therefore, by turning, we throw this part of the malt upon the top and the wet to the bottom, the steam of the wet malt from below must pass through the drier malt on the top, thus creating double work. The steam, also, by again passing through the drier malt on the top, tends to render it tough. If the kilns be properly constructed, turning is not only unnecessary, but injurious, until the malt be nearly ready for removal from the kiln, when several turns, with a brisk fire, may be necessary to render the dryness of the malt uniform; by which, also, the malt will be rendered uniformly mellow.
This, perhaps, may be thought merely theoretical; but the author’s own practice as a maltster, and also that of several experienced maltsters, to whom it has been communicated, and by them adopted, will prove the contrary.