WATER in the DISTILLERY Part I – Mineral Composition
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or anyone wanting to establish a distillery and looking for a suitable site, they have one essential first question: Is there sufficient water and, if so, is it available in the quantities that might be required? Quite simply, without sufficient water it is not possible to make the product. Out-of-specification water can be treated, but the cost and inconvenience of this has to be weighed against choosing a more suitable site. Water is utilized in drinks manufacturing, both as a raw material and as an integral part of the product, in addition to being used for cleaning and cooling. It is estimated that around 70 percent of water used in most drinks sectors is for cleaning, whereas in the distilled spirits industry the water burden is higher: 75 to 85 percent including condensation and cooling. In 2011, the scotch whisky industry estimated that it required 61.5 million m3/year, or around 47 liters of water per liter of product. However, it is important to remember that the term “water usage” is often ambiguous as the processes that are or are not included in water inventory can vary substantially. For instance, one estimate of water required to make beer is around 298 liters/liter beer, but this includes water usage for growing and malting barley, including production of any agrochemicals used. Specifically for water usage in a distillery, we can think of four applications: product water, water in process, water for general utility and additional water to pack lines, filters, etc., each having their own requirements. Process water is required for condensation and cooling duties and, as such, has no contact with the product. However, its pH is of importance, especially in copper condensers as higher acidities accelerate copper corrosion. Similarly, water for boiler feed to create steam should be substantially free of dissolved solids, which tend to concentrate during boiler operation, and be free of
WRITTEN BY PAUL HUGHES, PH.D.
It is estimated that around 70% of water used in most drinks sectors is for cleaning, whereas in the distilled spirits industry the water burden is higher: 75 to 85% including condensation and cooling. dissolved gases such as carbon dioxide and oxygen, which give rise to boiler corrosion. The quality of water for the product is more exacting and beyond the obvious potability criterion, product water requires deaeration and carbon filtration to remove chlorine and flavor-active contaminants. For final dilution low mineral content is preferred, especially for wood-matured spirits as long-chained fatty acids extracted from the wood can form insoluble precipitates with calcium. Both the European Union (EU) and the US Environmental Protection Agency (EPA) legislate for potable water. An EU directive in November 1998 set 62 measurable parameters, based on organoleptic, physicochemical, microbiological, toxic, and generally undesirable components.1 The EPA list is more comprehensive and includes disinfectant-derived components, inorganic and organic chemicals, micro-organisms and radionuclides.2 Whilst these legislative lists seem onerous, it is important to look at water from a positive perspective. For instance, most Scottish distillers rely on soft groundwater from springs, rivers, and lochs, with mains or well-water sources being less common.3
1 https://eur-lex. europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:31998L0083 &from=EN 2 (see https://www.epa.gov/sites/production/files/2016-06/documen ts/npwdr_complete_table.pdf) 3 https://www.alcademics.com/2013/ 04/tasting-the-regional-waters-of-scotland.html
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