An Analytical Method for Defining a Tawny Port Wine

Abstract

An analytical method for distinguishing ruby from tawny port was investigated. Color hue angles derived from tristimulus measurements increased with port age. When measuring individual ports in cells of increasing path length, hue angle increased in young ports, but decreased in old ports. Tint values also increased with port age, but remained constant with increasing cell path lengths. It is suggested that the transition of a ruby to a tawny port is indicated by the relative constancy of the hue angle with varying cell path length.