Article

VIRGIN OLIVE OIL SHELF LIFE: STUDY OF OIL STABILITY AT ROOM TEMPERATURE AND UNDER ACCELERATED STORAGE CONDITIONS

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Abstract

Virgin olive oil stability is very high in comparison with other vegetable oils. Accelerated shelf-life tests (ASLT) using temperatures around 100 degrees C are generally employed to estimate the induction period of the oxidation reaction in a short period of time, but no satisfactory correlation has been found with the VOO shelf-life at room temperature. The main goal of this research is, therefore, to study the chemical stability and the autoxidation process of VOO in the attempt to estimate the shelf-life of this product. A good correlation between the time required to reach EU Regulation upper limits for PV, K-232 and K-270, and the temperatures of the assay, up to 60 degrees C, by a potential equation in all samples studied was found. Moreover, a similar slope was obtained; this makes feasible to establish an ASLT method at a temperature below 60 degrees C to estimate shelf-life at room temperature.

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