Quantification of Total Phenolic and Carotenoid Content in Blackberries (<i>Rubus Fructicosus</i> L.) Using Near Infrared Spectroscopy (NIRS) and Multivariate Analysis
Eva María Toledo-Martín,
María del Carmen García-García,
Rafael Font,
José Manuel Moreno-Rojas,
María Salinas-Navarro,
Pedro Gómez,
Mercedes del Río-Celestino
Affiliations
Eva María Toledo-Martín
Department of Genomics and Biotecnology, IFAPA Center La Mojonera, Camino San Nicolás 1, La Mojonera, 04745 Almería, Spain
María del Carmen García-García
Department Agrifood Engineering and Technology, IFAPA Center La Mojonera, Camino San Nicolás 1, La Mojonera, 04745 Almería, Spain
Rafael Font
Department of Food Science and Health, IFAPA Center La Mojonera, Camino San Nicolás 1, La Mojonera, 04745 Almería, Spain
José Manuel Moreno-Rojas
Department of Food Science and Health, IFAPA Center Alameda del Obispo, 14080 Córdoba, Spain
María Salinas-Navarro
Department of Applied Biology (Genetic), University of Almería, Edificio CITE II-B, Ctra. Sacramento s/n, La Cañada de San Urbano, 04120 Almería, Spain
Pedro Gómez
Department of Genomics and Biotecnology, IFAPA Center La Mojonera, Camino San Nicolás 1, La Mojonera, 04745 Almería, Spain
Mercedes del Río-Celestino
Department of Genomics and Biotecnology, IFAPA Center La Mojonera, Camino San Nicolás 1, La Mojonera, 04745 Almería, Spain
A rapid method to quantify the total phenolic content (TPC) and total carotenoid content (TCC) in blackberries using near infrared spectroscopy (NIRS) was carried out aiming to provide reductions in analysis time and cost for the food industry. A total of 106 samples were analysed using the Folin-Ciocalteu method for TPC and a method based on Ultraviolet-Visible Spectrometer for TCC. The average contents found for TPC and TCC were 24.27 mg·g−1 dw and 8.30 µg·g−1 dw, respectively. Modified partial least squares (MPLS) regression was used for obtaining the calibration models of these compounds. The RPD (ratio of the standard deviation of the reference data to the standard error of prediction (SEP)) values from external validation for both TPC and TCC were between 1.5 < RPDp < 2.5 and RER values (ratio of the range in the reference data to SEP) were 5.92 for TPC and 8.63 for TCC. These values showed that both equations were suitable for screening purposes. MPLS loading plots showed a high contribution of sugars, chlorophyll, lipids and cellulose in the modelling of prediction equations.
