Abstract
The use of a voltammetric electronic tongue as a tool to monitor grape ripeness is proposed herein. The electronic
tongue consists of eight metallic electrodes housed inside a stainless steel cylinder. The study was carried out
over a period of ca. 1 month (August 2012) on different grape varieties (Macabeo, Chardonnay, Pinot Noir,
Cabernet Sauvignon, Shyrah, Merlot and Bobal) from various vineyards near Requena and Utiel (Valencia,
Spain). Apart from the electrochemical studies, the physico-chemical parameters, such as, Total Acidity, pH
and °Brix, were also determined in grapes. The PCA models, obtained using the physico-chemical or
electrochemical data, showed variation of ripenesswith time.Moreover the studywas completed by using partial
least squares (PLS) regression in an attempt to establish a correlation between the data collected from the
electronic tongue and Total Acidity, pH and °Brix values. A good predictive modelwas obtained for the prediction
of Total Acidity and °Brix. These results suggest the possibility of employing electronic tongues to monitor grape
ripeness and of, therefore, evaluating the right time for harvesting.
