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IVES 9 IVES Conference Series 9 NEAR INFRARED SPECTROSCOPY FOR THE ESTIMATION OF TEMPRANILLO BLANCO VOLATILE COMPOSITION ALONG GRAPE MATURATION

NEAR INFRARED SPECTROSCOPY FOR THE ESTIMATION OF TEMPRANILLO BLANCO VOLATILE COMPOSITION ALONG GRAPE MATURATION

Abstract

Grape volatile compounds are mainly responsible for wine aroma, so it is important to know the varietal aromatic composition throughout ripening process. Currently, there are no tools that allow measuring the aromatic composition of grapes, in intact berries and periodically, throughout ripening, in the vineyard or in the winery. For this reason, this work evaluated the use of near infrared spectroscopy (NIR) to estimate the aromatic composition and total soluble solids (TSS) of Tempranillo Blanco berries during ripening. For this purpose, NIR spectra (1100-2100 nm) were acquired from 240 samples of in-tact berries, collected at different dates, from veraison to overripening. From these same samples, the concentration of volatile compounds was analyzed using Thin Film-Solid Phase Microextraction-Gas Chromatography-Mass Spectrometry (TF-SPME-GC-MS), and the TSS were quantified by refractometry. Calibration, cross-validation and prediction models were built from spectral data using modified partial least squares regression (MPLS). Determination coefficients of cross-validation (R²CV) above 0.5 were obtained for all volatile compounds, their families, and TSS. These findings support that NIRS can be successfully use to estimate the aromatic composition as well as the TSS of intact Tempranillo Blanco berries in a non-destructive, fast, and contactless form, allowing simultaneous determination of technological and aromatic grape maturities.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Sandra Marín-San Román¹, Juan Fernández-Novales2,3, Cristina Cebrián-Tarancón⁴, Rosario Sánchez-Gómez⁴, María Paz Diago2,3, Teresa Garde-Cerdán1,*

1. Grupo VIENAP, Instituto de Ciencias de la Vid y del Vino (CSIC, Universidad de La Rioja, Gobierno de La Rioja). Ctra. de Burgos, Km. 6. 26007 Logroño, Spain. 
2. Grupo TELEVITIS, Instituto de Ciencias de la Vid y del Vino (Universidad de La Rioja, CSIC, Gobierno de La Rioja). Ctra. de Burgos, Km. 6. 26007 Logroño, Spain.
3. Departamento de Agricultura y Alimentación. Universidad de La Rioja. Madre de Dios 53. 26007 Logroño, Spain.
4. Cátedra de Química Agrícola, E.T.S. de Ingeniería Agronómica y de Montes y Biotecnología, Departamento de Ciencia y Tecnología Agroforestal y Genética, Universidad de Castilla-La Mancha. Avda. de España, s/n. 02071 Albacete, Spain

Contact the author*

Keywords

grape aromatic composition, NIR spectroscopy, non-destructive, TF-SPME

Tags

IVES Conference Series | OENO Macrowine | oeno macrowine 2023

Citation

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