Determination of Color Intensity of Whisky and Other Alcoholic Products

Abstract

A comparison is presented of color intensity values of aged and caramel-colored distilled alcoholic products obtained with spectrophotometers and colorimeters operated at different wavelengths. Absorbances measured by a narrow (≤1 nm) and an 8 nm bandwidth spectrophotometer at 430,525, and 610 nm are compared. Colorimeters evaluated include the Klett-Summerson equipped with Nos. 42, 54, and 60 regular filters and 520, 540, and 560 nm narrow bandpass filters and a Coleman Nepho-Colorimeter, equipped with a 525 nm filter. A conversion chart can be used to convert colorimeter units to absorbance units. The procedure suggested uses an instrument with a bandwidth ≤10 nm at a wavelength of 525 nm; results are reported in absorbance units.