The thirst for water in brewing industry
From cultivating barley right through to bottling, there is no doubt that it takes an exponential amount of water to make beer. The UK consultancy Water Strategies estimates it takes 300 litres of water to make one litre of beer. A WWF/SABMiller study suggests ratios anywhere from 60 to 180 to one. Even during the last stages in the production process, a typical pint of beer will have taken a further six pints of water to produce it.
With this huge water footprint, no efficient, environmentally friendly brewer would go into production without water at the very top of the agenda. Not only is it a key factor in influencing taste, but it’s a major cost in the brewing process. Furthermore, consumers now expect brewers to have an environmentally friendly process in place to help deal with the world’s chronic water shortage position and future risks.
For these reasons, few brewers would consider using water straight from the tap unless no other option exists. The cost would be prohibitive, and the mineral content of tap water would certainly compromise the taste which would impact on consumer drinking decisions. For instance, the water of Pilsen (where Pilsner originated) is very soft, free of minerals, and very low in bicarbonates. Brewers in this region typically added salts to raise the hardness in the water. On the other hand, brewers in Burton-upon-Trent (famous for its IPAs) frequently pre-boil their water to reduce the hardness.
When devising a water strategy for a new brewery, the smart brewer will have to consider both the initial processing of water and the reclamation or recycling of water to minimise costs and comply with Environmental Agency effluent regulations.
The location of the new brewery will have a significant impact on how water is used. Breweries with easy access to natural water sources like rivers and lakes will be at a natural economic advantage being able to extract and process water with relative ease but which may still require processing to deliver the consumer quality required. But don’t forget, putting water back into the system is just as important as there are tough environmental regulations governing disposal of effluent. However, being on the banks of the river is not always the best solution. Take Guinness, for example. They do not extract water from the River Liffey but pipe their low mineral content water from the nearby Wicklow Mountains. A little less appealing than fresh mountain water is the Californian pale ale Full Circle which is made from recycled sewage water!
But regardless of the source of water, it will have to almost certainly need to undergo some form of treatment before being considered fit for quality brewing.
Typically, there are three main technologies for processing water. Reverse Osmosis, filtration and carbon filtration.
Revserse Osmosis
Reverse osmosis (RO) is a water purification technology that uses a semipermeable membrane to remove ions, molecules and larger particles from drinking water. A high-pressure pump forces the contaminated water through a fine mesh to capture the unwanted particles.
Kirton has 40 years’ experience of installing reverse osmosis systems for food and drink processors including breweries who prize this technology to create a precise recipe for their beer.
The RO water-treatment method removes impurities, minerals, and just about everything else in a water source. With an RO setup, a brewery can take whatever water they’ve got, strip it down to almost pure H2O, and build it back up to their exact specifications.
Nanofiltration
Nanofiltration is a membrane filtration-based method that uses nanometer sized through-pores that pass through the membrane. Nanofiltration membranes have pore sizes from 1-10 nanometers, smaller than that used in microfiltration and ultrafiltration, but just larger than that in reverse osmosis. Nanofiltration is used where the high salt rejection of reverse osmosis is not necessary, and yet NF is still capable of removing hardness elements such as calcium or magnesium.
Carbon filtration
Carbon filtering is a method of filtering that uses a bed of activated carbon to remove contaminants and impurities, using chemical adsorption. Carbon filtering is commonly used for water purification, air filtering and industrial gas processing, for example the removal of siloxanes and hydrogen sulfide from biogas. It is also used in a number of other applications, including respirator masks, the purification of sugarcane and in the recovery of precious metals, especially gold. It is also used in cigarette filters.
Processing water though is just one side of the equation for the brewer. Water reclamation provides another cost-effective and environmentally sound way of optimising water use. Given that six pints of water are used for every one of beer, there are clearly opportunities to recycle.
The UK’s Westons Cider revealed that the use of a RO water treatment system from Spirax Sarco was saving the company some £42,000 (EUR60,000) per year in fuel and water costs for its boiler, a 2,000kg/h unit producing steam for various process duties, including pasteurisation and cleaning.
The RO system achieved saving by cutting the amount of boiler blow down and water needed to prevent dissolved solids from accumulating in the boiler, where they can cause problems such as foaming and scale. A cut in blowdown from 3% to less than 1% has been achieved, the company says.
In summary water is a critical resource for quality beer manufacture and there are 3 key component areas for a brewer to consider;
1. The quality and composition of the water that is used in the brewing process
2. The content of the water that is passed to waste as a by-product of the brewing process
3. The composition and content of the water utilised in any of the supporting processes e.g. boiler systems to ensure the uptime and efficiency of the manufacturing process.
This necessitates attention to detail continuously to ensure that the highest quality of product is achieved, the most efficient cost structure is delivered and the compliance with ever increasing Environmental regulations are met.
This articles first appeared in The Brewers Journal
