2026-09-15T23:26:52Zhttps://gredos.usal.es/oai/request

oai:gredos.usal.es:10366/1605732025-04-30T20:39:50Zcom_10366_137028com_10366_4512com_10366_3823col_10366_137029

Valderrama, Patricia Rodríguez-Fernández, Marta Revilla Martín, Isabel Hernández Jiménez, Miriam Martínez Martín, Iván Vivar Quintana, Ana María 2024-11-11T09:06:02Z 2024-11-11T09:06:02Z 2024-01-31 Revilla, I., Hernández Jiménez, M., Martínez-Martín, I., Valderrama, P., Rodríguez-Fernández, M., & Vivar-Quintana, A. M. (2024). The Potential Use of Near Infrared Spectroscopy (NIRS) to Determine the Heavy Metals and the Percentage of Blends in Tea. Foods (Basel, Switzerland), 13(3), 450. https://doi.org/10.3390/foods13030450 http://hdl.handle.net/10366/160573 10.3390/foods13030450 [EN] The following study analyzed the potential of Near Infrared Spectroscopy (NIRS) to predict the metal composition (Al, Pb, As, Hg and Cu) of tea and for establishing discriminant models for pure teas (green, red, and black) and their different blends. A total of 322 samples of pure black, red, and green teas and binary blends were analyzed. The results showed that pure red teas had the highest content of As and Pb, green teas were the only ones containing Hg, and black teas showed higher levels of Cu. NIRS allowed to predict the content of Al, Pb, As, Hg, and Cu with ratio performance deviation values > 3 for all of them. Additionally, it was possible to discriminate pure samples from their respective blends with an accuracy of 98.3% in calibration and 92.3% in validation. However, when the samples were discriminated according to the percentage of blending (>95%, 95-85%, 85-75%, or 75-50% of pure tea) 100% of the samples of 10 out of 12 groups were correctly classified in calibration, but only the groups with a level of pure tea of >95% showed 100% of the samples as being correctly classified as to validation. eng MDPI NIRS (Near Infrared Spectroscopy) Residual Mean Square residuals Black tea Green tea Red tea Espectroscopía del infrarrojo cercano Suma residual de cuadrados Té negro Té verde Té rojo 2209.21 Espectroscopia The Potential Use of Near Infrared Spectroscopy (NIRS) to Determine the Heavy Metals and the Percentage of Blends in Tea info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion https://doi.org/10.3390/foods13030450 info:eu-repo/semantics/openAccess Foods 13 450