Researchers at the University of Seville (Spain) have developed a technique for estimating grape composition and variety using computer imaging. They have also put forward an index for identifying the ripeness of seeds without the need for chemical analysis. This new method can help to decide the best moment for picking.
The normal procedure for identifying the sugar content of grapes involves chemical analysis. But this is a long and tedious task that tells vine-growers when to start picking their grapes. Now though, scientists at the University of Seville (US) are proposing an alternative technique: photographing grapes and analysing the images.
The method consists of inserting the fruit or seeds into a light controlled cabin. Computer imaging then identifies exact colour in accordance with International Commission on Illumination standards along with morphological characteristics such as length, width and sphericity.
Lastly, using software developed by the researchers themselves, the variety of samples can be recognised by comparison with a pre-established database of images.
Published in the 'Computers and Electronics in Agriculture' journal, the study has been successfully validated in vineyards with the Denomination of Origin Condado de Huelva. The machine is capable of differentiating whether the grape is of the Tempranillo, Syrah or the native Zalema variety.
"The advantage of this technique is that it offers automated and speedy quality control and inspection as well as objective monitoring of the ripening process," as explained to SINC by Francisco J. Heredia, one of the authors and coordinator of the Food Colour and Quality Group of the US.
The researcher also highlights that they conceived a "browning index" for seeds a parameter that estimates ripening stage regardless of variety and harvest year "solely using data provided by the images."
Revelation of phenolic content wit
FECYT - Spanish Foundation for Science and Technology