| 摘要 |
<p>A beer froth measuring instrument includes a light source and a photoreceiver which are mounted on a platform and can be moved vertically along a transparent measuring cylinder in which beer has been poured to generate a head of froth. The light rays, pref. of a pulsed nature, are absorbed more by the fine creamy froth than by the loose large bubbles above it or the liq. beer below it, and a record is produced after the transmitted light rays have been converted to electric signals and amplified. A repetition of the measurements in time gives a record of the formation and duration of the creamy froth and gives an objective quality control.</p> |
