Colour profile analysis of Port wines by various instrumental and visual methods.

Background: Wine colour is an important quality parameter, being the first sensorial attribute evaluated during wine tasting. The perception of wine colour can be different depending on many factors, including the depth of the sample under observation. The main objectives of the present study were to measure the colour of Port wines using CIE L*, a*, b* parameters at different depths with various instrumental techniques (spectrophotometry and colorimetry), and to compare the obtained results with the sensory (visual) perception of colour samples.