Aromatização do azeite de oliva extravirgem com alecrim usando ultrassom

Abstract

Olive oil is obtained from the olive tree (Olea europaea L.) through the application of mechanical and/or physical methods. Initially, consumption of olive oil was restricted to Mediterranean countries, but due to nutritional, sensory and health benefits, there was an increase in the popularity of olive oil worldwide. The olive growing sector is booming in Brazil, especially in the state of Rio Grande do Sul, where there are currently 160 producers in 55 cities, with 6 industries and 11 brands of extra virgin olive oil. In this scenario, the aromatization of extra virgin olive oil with spices increases the nutritional value of the final product, besides being a strategy to diversify products and add value to extra virgin olive oil. Thus, the use of clean and innovative technologies can be explored in order to accelerate and increase the migration of volatile and bioactive compounds from spices to olive oil. Thus, this study aims to verify if ultrasound technology can actually accelerate the aromatization process of extra virgin olive oil, and how it affects the oxidative stability and chemical composition of the aromatizes product. For the development of the aromatization process of olive oil through ultrasound assisted infusion, it was necessary to optimize the operating conditions of the ultrasound through a central composite planning with three variables at two levels (23), with central points and axial forces. The variables were the ultrasound amplitude, the extraction time and the temperature during the extraction, with quadruplicate of the central point, resulting in 18 experiments. Then, the aromatization of olive oil with ultrasound assisted infusion with dry leaves of rosemary was carried out. It was evaluated the raw material (EVOO), olive oil aromatizado with the use of ultrasound (UAI) and the conventional method (IC) through the analysis of free fatty acids (FFA), peroxide index (PV), extinction coefficients (K232, K270 and ΔK), total phenolics compounds (TPC), antioxidant capacity (ORAC), oxidative stability by rancimat, polar compounds, fatty acid (FA) profile and volatile compounds (VOCs). It was then observed that the raw material is in accordance with a "Arbequina monovarietal extra virgin olive oil ", and correctly classified according to the current legislation. It was concluded that the use of ultrasound technology accelerates the process of aromatization of olive oil with rosemary leaves, causing the migration of volatile compounds, adding value to the final product obtained and improving its oxidative stability and, consequently, increasing its shelf life.