Vol. 70 No: 5

Title:
Colour Changes Associated with Maturation of the Table Grape cv. Don Mariano

Authors:
J. CARREÑO L. ALMELA, A. MARTÍNEZ and J.A. FERNÁNDEZ-LÓPEZ

pp: 841-846

Abstract:
The use of colour to appraise the ripeness of grapes is usually a subjective procedure. To make a close study of changes in the external colour of ‘Don Mariano’ grapes during ripening the colour and physico-chemical characteristics of grape berries were examine at six ripening stages from the change of colour of the fruit (veraison) to commercia lmaturity (harvesting). Colour measurements were made with a tristimulus colorimeter (L*, a*, b*, h and C* values were registered) and data were analyzed by multivariate analysis. A colour index for red grape (CIRG), defined as (180 - h)/(L* + C*) was used to standardize objectively the changes in surface colour. Our results showed that L*, b*, h and C* decreased during ripeness while a* increased during the first ripening stages and decreased in the last due to the presence of violet tints in the grape berry. The CIRG and maturity index (°Brix/titratable acidity) were highly correlated (r = 0.935, P<0.01), showing that the CIRG is a suitable way of objectively standardizing both colour levels and maturity.

Full text: JHSB Subscribers     ISHS members & other users
(PDF 312826 bytes)

Translate:

Go back to previous page