Kilning, barley

Investment, Costs, and Prices for Barley and Malt. Estimated malthouse investment (1993) and costs for a new malthouse with annual capacity of 120,000 t are shown in Table 2. This malthouse is equipped with twelve 1,700-bushel steep tanks, eight 10,000-bushel germination compartments, and two double-deck kilns. The kilns are equipped with standard heat recovery units and indirect heat. 

A wide variety of special malts are produced which impart different flavor characteristics to beers. These malts are made from green (malt that has not been dried) or finished malts by roasting at elevated temperatures or by adjusting temperature profiles during kilning. A partial Hst of specialty malts includes standard malts, ie, standard brewers, lager, ale, Vienna, and wheat caramelized malts, ie, Munich, caramel, and dextrine and roasted products, ie, amber, chocolate, black, and roasted barley. 

MN Maillard, C Berset. Evolution of antioxidant activity during kilning Role of insoluble bound phenolic acids of barley and malt. J Agric Food Chem 43 1789-1793, 1995. 

Malt is produced by steeping barley in water for several days. This initiates germination, which activates several enzymes important in the digestive process that occurs in malt. The germinated barley is then dried and kilned at about 80°C, or higher for darker malts. 

Made from barley malt and having a smoky taste, obtained by using peat instead of coal as fuel in the kiln drying of the malt. Changes in the variety of peat used materially affect the flavor. This includes scotch whiskeys commonly classified in the British Isles as follows (1) Highland malts, (2) Lowland malts, (3) Campbell towns, (4) Islays. 

The principles involved in hop drying are similar to those involved in barley drying and the kilning of malt (see Vol. I, Chapter 6). 

In addition to the use of nitrite and nitrate as additives, a second general mechanism by which foods may become contaminated with NA is through the drying of foods in air which has been directly heated in an open flame. The highest levels of VNA resulting from this common method of food processing have been in the kilning of malted barley. Concentrations of NDMA in the dried malt of over 100 yg/kg have been reported (Hotchkiss et al. 1980 Preussmann et al. 1981). 

Hugues M., Boivin P., Gauillard F., Nicolas J., Thiry J-M and Richard-Forget F. (1994) Two lipoxygenases from germinating barley-heat and kilning stability, J. Food Sci. 59 (4) 885-889. 

Light malt requires fast drying so that the Mail-lard reaction does not get a look-in. The process is carried out in high-performance kilns at a temperature which is raised from 50 to 65 °C. The barley heats up and germination stops above 40 °C at a water content which is reduced to 20%. However, the activities of hydrolases (endopepti-dases, a-amylases) still increase, as desired. The final drying is carried out at 82-85 °C, leading to unavoidable enzyme losses. 

Whiskey, depending on the kind, is made by different processes. The raw material for Scotch single malt whiskey is barley malt which has been exposed to peat moss or coal smoke during kiln drying. Such smoked malt is mashed at 60 °C and filtered. The resulting wort is then fermented at 20-32 °C after the addition of yeast (Saccha-romyces cerevisiae). Irish whiskey is never made from smoked malt. The distillation is conducted in two steps, sometimes in simple pot stills. The harsh, raw liquor is collected in the first distillation step. The undesirable harsh components are removed in the head and tail fractions in the second distillation. 

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