DEVELOPMENT OF A MECHANICAL TEXTURE TEST TO EVALUATE THE RIPENING PROCESS OF CABERNET FRANC GRAPES

ABSTRACT There is scant literature on the assessment and validation of methods for monitoring grape texture during ripening. There is a distinct lack of information from published work on the correct procedures to set up texture method. If the measurement of grape texture is to be used for assessing ripeness and further extended to the assessment of polyphenol extractability potential, the relationship between physicochemical parameters and sensory descriptors should be evaluated as a matter of importance. In this work, the physical properties of grape texture during ripening were addressed by an assessment of the relationship between the methods of double compression and puncture tests. The second part of the study reported here applied the methods developed in the first year to grapes sampled in the following year. The results showed that the mechanical texture measurements were able to discriminate grapes coming from different parcels and correlations were found between texture parameters and sensory descriptors. PRACTICAL APPLICATIONSThis paper defines the measurement conditions for monitoring grape texture, particularly during ripening. These established methodologies provide enologists with the tools to monitor the progress of grape maturity, and these mechanical methods compare favorably with the expensive and time‐consuming classical methods. These established methodologies could also be used to highlight important information on grape evolution during ripening and help to provide better insight on the choice of the preferred/ideal harvest date. These tools, providing enologists with data on the evolution of fruit texture, could be used to help select more suitable winemaking processes as well, as the extractability of compounds present in the fruit is probably linked to its texture.