MALTING.
Malting is the process of preparing cereals through germination or growth for purposes of mashing and fermentation. Barley is the grain commonly used for making malt for lager beer, ale, stout, vinegar and yeast-makers' or dis tillers' mash, etc., while wheat malt is used to a large extent in the production of weiss beer. The barley is first cleaned in order to remove foreign seeds, straw, broken kernels, etc., by means of sieves and blower fans. As the character of the beer depends largely upon that of the malt, and as the latter's character can be determined during malting, it follows that there are various methods of details in malting. The following are the general manipulations em ployed: Steeping.— Malting is in reality an artificial or forced growth of a seed, the changes taking place being similar to those when the seed is planted in the soil. The first requisite is mois ture. This is given to the grain by placing it in steep tanks containing water of a certain temperature. Steep tanks are cylindrical iron vessels having conical bottoms so that all the grain will drop out when tank is emptied. They are generally placed on the top floor of the malthouse. The grain remains in the steep tank until it has absorbed the desired amount of water, the time differing for different kinds and quality of grain or the process of the malt ster. For barley the duration of steeping is generally from 36 to 60 hours, averaging about 48 hours.
Growing or Germinating The malthouse usually consists of several floors. The water in the steep tank is drained off and the wet barley dropped upon these floors be low. The barley is now spread in heaps of about 12 to 14 inches high (occupying rather more than one-third and less than one-half of the floor space). The barley now dries out somewhat and begins to sprout or grow and small hair-like fibres, called rootlets, begin to show. As heat is generated during growth, which is undesirable above a certain tempera ture, and as further proper growth requires pure air, it is necessary to aerate the growing barley (now called green malt). This is done
by what is called "turning the heap," which con sists of reshoveling the green malt in such a manner that the lower kernels of the old heap will be at the top in the new heap. (During turning, the green malt is thrown through the air in a thin sheet or stream, whereby it is aerated and cooled. The new heap now oc cupies a larger floor space, is consequently of less height on the floor). This turning is re peated at regular intervals so that at the end of the growing period the heap covers the entire floor to a height of from five to six inches. This growth usually takes about five days, during which time water is sprinkled upon the heap whenever it becomes too dry.
Kilning or Drying.— After the green malt shows the desired degree of sprouting, it is necessary to quickly check further growth. This is done by drying it upon the kiln. The green malt is shoveled by means of a power shovel to one end of the floor where it drops through an opening into a bucket elevator and is conveyed to the kiln. The kiln usually has two floors placed one above the other made of strips of wire or perforated sheet metal and heated by means of an open fire from below. Above the upper floor, in the dome, drafts are placed to carry off the vapors, but in modern constructions suction fans are used to promote drying. The green malt is spread evenly upon the upper kiln floor about 18 inches high, where it remains for 24 hours, during which time it is only partially dried. It is now dumped or dropped upon the lower floor (commonly by mechanical dumping floors which turn open in sections on an axis or bearing like the grate in a furnace). The malt on this lower kiln is again spread evenly and then subjected to a higher temperature until the desired degree of dryness is obtained, which usually takes from 20 to 24 hours.