INFLUENCE OF LIGHT ON THE STABILITY AND SHELF LIFE OF OLIVE OIL
Extra virgin olive oil is obtained from olives using only mechanical processing steps under slight thermal conditions. Although this oil is a high-quality oil, its shelf life during storage is limited due to oxidative and hydrolytic degradations. The main factors involved in oxidation are high temperatures and light, accelerating rancidity and catalyzing the process by increasing peroxide formation. The effect of light was studied in several works but in other conditions (commercial olive oils, short storage or other cultivars). The aim of this work was to study the effect of light during 9 months of storage on the stability of Verdeña olive oil extracted in Abencor. The storage conditions involved transparent plastic containers at room temperature in the presence of direct light or in darkness. Physicochemical and nutritional parameters of olive oil were analyzed after extraction and during storage. During the storage period, increases in the free acidity, peroxide index, and absorption coefficients K232 and K270 were observed in both cases but were higher in the presence of direct light. The alpha-tocopherol content decreased more sharply in the presence of light. Total phenols content decreased similarly whether in darkness or in the presence of light. The results show that direct light decreases the olive oil shelf life, and in consequence it is advisable to keep olive oil at adequate temperature and in opaque containers.
Benito, M., Abenoza, M., Oria , R. and Sánchez-Gimeno, A.C. (2011). INFLUENCE OF LIGHT ON THE STABILITY AND SHELF LIFE OF OLIVE OIL. Acta Hortic. 924, 413-418
darkness, oxidation, rancidity, storage