New beer filter
July 12, 2004 - A defunct technology developed for magnetic tapes 10 years ago is being used to make a superfine filter that makes beer clearer and brighter.
According to New Scientist, the Digital Compact Cassette tape format was designed in the early 1990s by Philips of The Netherlands which used record/playback heads to write or read magnetic data through 70 micrometres wide holes. The company used a beam of hot fluorocarbon plasma to blast the holes in a metal film.
A Dutch, Fluxxion, has adopted the hole-blasting technology to make a new class of fluid filters. A 15-centimetre-wide silicon wafer disc is placed in a vacuum and a plasma beam blasts 3 billion 0.45-micrometre holes it. The wafer is then rinsed. The ultra-fine filter helps to remove cloudy yeast residues from beer unlike conventional filters.
Fluxxion is also testing the filter on milk to see if it can filter out bacteria and thus avoid pasteurization, which can impair the taste. This technique could also be used by craft brewers who want to retain the fuller flavor washed out by pasteurization.