Effect of malaxation temperature on the physicochemical and sensory quality of cv. Cobrançosa olive oil and its evaluation using an electronic tongue

Abstract

Olive oil is consumed worldwide due to its appreciated sensory attributes and health benefits, which are related with its fatty acid profile and richness in phenolic compounds that support a health claim concerning olive oil protective effects on blood lipids. However, to ensure that oils possess a rich phenolic content, the extraction conditions can be optimised. Therefore, the effects of malaxation temperature (22, 28 and 34 ºC) on the physicochemical and sensory characteristics of cv. Cobrançosa olive oils were evaluated. The oils extracted at 22 ºC had an overall better physicochemical quality (higher total phenols content, greater oxidative stability, lower free acidity and oxidation markers) and more intense positive sensory sensations (higher bitterness and pungency). Additionally, this study showed that a potentiometric electronic tongue could be used to discriminate oils taking into account the effect of malaxation temperature on the overall physicochemical and sensory scores (all samples correctly classified for leave-one-out cross-validation) with a predictive classification similar to that achieved by trained panellists. This finding strengthens the hypothesis that this device could be used as a complementary/alternative taste tool for assessing the impact of the extraction conditions on the oils physicochemical and sensory characteristics.