title: Screening of anthocyanins in single red grapes using a non-destructive method based on the near infrared hyperspectral technology and chemometrics.
abstract: BACKGROUND
  Anthocyanins are the main compounds responsible for the colour of red wines and therefore it may be important to evaluate the content of the aforesaid secondary metabolites during grape ripening due to the crucial importance to determine wine colour. Nowadays, there is a growing demand of rapid and non-destructive analytical tools for analysing grapes, such as the emerging hyperspectral analysis.
  
  
  RESULTS
  The hyperspectral images of intact grapes (Vitis vinifera L. cv. Tempranillo, Graciano, Garnacha and Mazuelo red grape from vineyards located in the D.O.Ca. Rioja at two different developmental stages) were recorded using a near infrared hyperspectral imaging device (900-1700 nm). Reference values of anthocyanins were obtained by HPLC-DAD. Calibrations were performed by modified partial least squares regression and present a good potential (coefficient of determination of 0.72 and standard error of cross-validation values of 0.78 and 0.70 mg per grape for total and non-acylated anthocyanins respectively).
  
  
  CONCLUSIONS
  The procedure reported here presents a good potential for a fast and reasonably inexpensive screening of these compounds in intact single berries. Moreover, the heterogeneity of anthocyanins within the same ripeness stage could be evaluated using this non-detructive tool.
authors.affiliation: Autonomous University of Baja California (UABC), Faculty of Engineering, Architecture and Design (FIAD), Kilometro 106 carretera Tijuana-Ensenada, Ensenada, Baja California, Mexico.
authors.forename: Jesús Raúl
authors.initials: JR
authors.lastname: Martínez-Sandoval
authors.affiliation: Food Colour & Quality Laboratory, Department of Nutrition & Food Science, Universidad de Sevilla, Facultad de Farmacia, 41012, Seville, Spain.
authors.forename: Julio
authors.initials: J
authors.lastname: Nogales-Bueno
authors.affiliation: Food Colour & Quality Laboratory, Department of Nutrition & Food Science, Universidad de Sevilla, Facultad de Farmacia, 41012, Seville, Spain.
authors.forename: Francisco José
authors.initials: FJ
authors.lastname: Rodríguez-Pulido
authors.affiliation: Food Colour & Quality Laboratory, Department of Nutrition & Food Science, Universidad de Sevilla, Facultad de Farmacia, 41012, Seville, Spain.
authors.forename: José Miguel
authors.initials: JM
authors.lastname: Hernández-Hierro
authors.affiliation: Center of Scientific Research and Higher Education of Ensenada (CICESE), Carretera Ensenada-Tijuana No. 3918 Zona Playitas, CP: 22860, Ensenada, Baja California, Mexico.
authors.forename: Manuel Alberto
authors.initials: MA
authors.lastname: Segovia-Quintero
authors.affiliation: Autonomous University of Baja California (UABC), Faculty of Engineering, Architecture and Design (FIAD), Kilometro 106 carretera Tijuana-Ensenada, Ensenada, Baja California, Mexico.
authors.forename: Miguel Enrique
authors.initials: ME
authors.lastname: Martínez-Rosas
authors.affiliation: Food Colour & Quality Laboratory, Department of Nutrition & Food Science, Universidad de Sevilla, Facultad de Farmacia, 41012, Seville, Spain.
authors.forename: Francisco José
authors.identifier: http://orcid.org/0000-0002-3849-8284
authors.initials: FJ
authors.lastname: Heredia
mesh_terms: D000872:Anthocyanins / Q000737:chemistry*; D005504:Food Analysis; D019265:Spectroscopy, Near-Infrared / Q000379:methods*; D027843:Vitis / Q000737:chemistry*
chemical_list: D000872:Anthocyanins
keywords: anthocyanins; chemometrics; grapes; hyperspectral imaging; near infrared