Dynamic viscosity of olive oil as a function of composition and temperature: A first approach

Abstract

AbstractKnowledge of the viscosity of virgin olive oils (VOOs) is of great importance for the design of pilot plants, to determine the time required for the settling of particles at the end of the production chain and from a sensory view point. The dynamic viscosities of French VOOs from four different cultivars (‘Aglandau’, ‘Bouteillan’, ‘Salonenque’ and ‘Tanche’) were studied as a function of their fatty acid and TAG compositions and of the temperature [10–50°C]. These four VOOs had different TAG and fatty acid compositions representative of the range of compositional variations in the main French oils. Their viscosities were similar, although small but measurable differences that depended on their compositions were apparent. All the VOO samples exhibited the same dynamic viscosity pattern over temperature. For a given temperature, the viscosity difference was the greatest between Aglandau and Salonenque oils, Aglandau being the oil with the highest viscosity. The correlation between temperature and viscosity was highlighted by an Arrhenius model for this Newtonian fluid. The Arrhenius activation energy was correlated (R2 = 0.993) with the percentage of triolein, the main TAG in olive oil.