Ultrafiltration wins over precoat for vinegar
12 Jun 2000
At Hazlewood Manor Brewery in Burntwood, Staffordshire, a membrane-based ultrafiltration system has replaced a precoat pressure filter system for clarifying malt and spirit vinegar. Supplied by Koch Membrane Systems, the clarification plant consists of two ultrafilters, one for malt and the other for spirit vinegar. Each is made up of 24, 5in diameter, hollow fibre ultrafiltration cartridges capable of treating up to 15m3/h of vinegar, which makes the Hazlewood plant the largest of its kind in the world.
The vinegar is produced in a double fermentation process. For malt vinegar, drained liquor from malted barley mash is fermented to produce alcohol, which is then converted to vinegar with special bacteria. Spirit vinegar, on the other hand, is made from alcohol from fermented sugar beet liquor or molasses.
Previously, candle filters coated with diatomaceous earth filtered the vinegars prior to bottling. But since installing the Koch systems, Hazlewood has found it is consistently achieving a much cleaner product in less than half the time. The new process has also delivered significant environmental benefits, in that the plant is much cleaner and the need to landfill the discharged diatomaceous earth has been eliminated.
