Caracterização de óleos vegetais e azeites através de espectroscopia de infravermelho próximo com transformada de Fourier (FT-NIR)

Mestrado em Engenharia Alimentar - Qualidade e Segurança Alimentar - Instituto Superior de AgronomiaThe main goal of the present work was the application of near infrared spectroscopy (NIR) in the characterization of soybean oil, sunflower oil, extra virgin olive oil and olive oil. Firstly, the models provided by Bruker, the equipment manufacturer, were validated. These models are related to the fatty acid composition and acidity for oils and olive oils, iodine value for oils and peroxide value, ultraviolet absorbance (232 and 270 nm), -sitosterol and total sterols in olive oils. Simultaneously calibration models were developed for the individual oils (fatty acid composition, iodine value, anisidine value and the ultraviolet absorbance (230 and 270 nm) and olive oils (acidity, fatty acid composition, -sitosterol, total sterol, absorbance at 232 nm, erythrodiol and uvaol). Also two calibration models were developed for the quantification of stigmastadienes in extra virgin olive oils, to detect and quantify the presence of soybean oil or sunflower oil. Both models proved promising – sunflower oil (r2 = 0,94; RMSECV = 0,013 ppm; RPD = 3,95) and soybean oil (r2 = 0,70; RMSECV = 0,054 ppm; RPD = 1,82). However, it is necessary to analyze a greater number of samples to carry out an external validatio