Impact of thermal sterilization on the physicochemical-sensory characteristics of Californian-style black olives and its assessment using an electronic tongue

Abstract

The effect of thermal sterilization processes on the physicochemical parameters and sensory characteristics of Californian-style black olives, from ‘Hojiblanca’ and ‘Manzanilla Cacereña’ brine solutions, were evaluated. Two-way ANOVA showed that ‘Hojiblanca’ olives had a lower phenols content and defect intensity and that increasing the sterilization period resulted in a decrease in total phenols and an increase of the cooked defect. The impact of thermal sterilization was further evaluated using a potentiometric electronic tongue, which was capable of discriminating the different sterilization treatments (repeated K-fold cross-validation sensitivity: 89.0 ± 15.0% to 97.0 ± 6.0%). Moreover, multiple regressions allowed the prediction of phenols (R2 ≥ 0.95 ± 0.03) and the intensity of the defect (R2 ≥ 0.95 ± 0.04). These results point out the feasibility of the electronic tongue as an analytical tool for monitoring the effects of thermal sterilization treatments. Furthermore, the satisfactory results obtained for the brine solutions may foresee a practical non-destructive method for indirect quality assessment of table olives.