A unit measuring the density of milk. 1 degree Quevenne represents a difference in specific gravity of 0.001, so, for example, 20oQ milk has specific density 1.020
Russ Rowlett (Director), How Many? A Dictionary of Units of Measurement, Center for Mathematics and Science Education University of North Carolina, USA 2005. http://www.unc.edu/~rowlett/units/dictA.html, (Unit of Meas and Covr Factors - Amer) {608}