Uso de ultrassom na síntese de diacilglicerol via hidrólise enzimática de óleo de girassol

Abstract

Oils and fats are essential foods to the human diet, nevertheless, the negative impact caused by its overconsumption is of great concern worldwide. Diacylglycerol rich oils have orga- noleptic features very similar to those found in conventional edible oils, however, these oils do not tend to accumulate on the body, even when consumed in high quantities, becoming a great resource in the fight against obesity. Sunflower oil is among the most consumed edible oils in the world, and also, is naturally one of the healthiest. This study s goal was to evalu- ate the influence of ultrasound on the enzymatic hydrolysis of sunflower oil with the enzyme phospolipase A1 (Lecitase Ultra) and use mathematical modeling to obtain simulations of production processes of a diacylglycerol rich oil. Ultrasound generates emulsions of water and oil, thus enhancing the system s interfacial area, and producing higher reaction rates compared to conventional enzymatic processes. Sunflower oil partial hydrolysis was carried in a solvent free environment, in 4 hour periods, with temperatures varying from 30 to 50 °C, enzyme/substrate fractions between 0,6 and 4,0% (m/m) and a fixed water/oil fraction of 5% (m/m). with this goal in mind, experimental designs were developed. Results showed optimal reaction conditions on 40 °C and 1,7% (m/m). Subsequently, fixing the optimal parameters, water/oil fraction was evaluated between 2 and 10% (m/m) in a 12 hour period in order to obtain reaction kinetics. Applying a mathematical model to the kinetic curves it was possible to demonstrate that, for the tested fractions, the 2% water/oil ratio is the most favorable to the production of diacylglycerol, and the maximum quantity of this product is obtained at 27 minutes of reaction time.