Characterization of Natural Orange Juices Employing Physicochemical Properties and FTIR Spectroscopy: A Study with the Storage Time
In this work, the physicochemical properties and the infrared spectra of three different natural orange juices derived from the sour orange (Citrus aurantium), the common orange (Citrus bigardia Riss) and the sweet orange (Citrus sinensis) varieties, named A, C, and D respectively were studied at room temperature with the storage days during the 92 days. The physicochemical properties studied were the pH, refractive index, density, conductivity and the quantity of total soluble solids expressed as degree Brix. The natural A and C juices show a great quantity of bands attributed principally to the ascorbic and citric acid while the natural D juice evidence a higher content of bands associated with sucrose. The assignments of the bands observed in the infrared spectra of the natural A, C and D varieties in the 4000-400 cm-1 region was proposed. From the three natural studied juices, the D juice is the most instable with the time, as evidenced by the Infrared (IR) spectra and the physicochemical properties.
Laura Cecilia Bichara, Hernán Enrique Lanús, María Jimena Márquez and Silvia Antonia Brandán