Background and Aims: Modern viticulture requires robust, fast, non-destructive methods to assess berry composition. We tested a chlorophyll fluorescence screening method to estimate berry phenolic substances. Methods and Results: We focused on anthocyanin and flavonol in red and white cultivars. The ANTH_RG indexwas dependent on the cultivar anthocyanin profile. In Nebbiolo, in which dihydroxylated anthocyanins prevail, ANTH_RG was 2.4 times higher than in Barbera, in which trihydroxylated anthocyanins prevail. Considering the profiles of the two cultivars at similar anthocyanin concentration and their relative in vitro absorbance, a bathochromic shift of 10 nm emerged, which can explain the different screening effect exerted by anthocyanin on chlorophyll fluorescence. As to flavanols, we propose the calibration of a new spectroscopic index, the FLAV_UV, in coloured and white berries, finding good correlation with flavonol concentration determined analytically (R2 higher than 0.7). Conclusions: Spectroscopic indices can estimate the concentration of anthocyanin and flavonol in grape berries. Significance of the Study: A calibration curve for Nebbiolo, which has a distinctive anthocyanin profile, and the calibration of a new index, the FLAV_UV, able to estimate flavonol concentration in both red and white cultivars, are described for the first time. These indices can effectively be applied for non-destructive assessment of grape flavonoid.

Improved fluorescence-based evaluation of flavonoid in red and white winegrape cultivars

FERRANDINO, Alessandra
First
;
PAGLIARANI, CHIARA;CARLOMAGNO, ANTONIO;NOVELLO, Vittorino;SCHUBERT, Andrea;
2017

Abstract

Background and Aims: Modern viticulture requires robust, fast, non-destructive methods to assess berry composition. We tested a chlorophyll fluorescence screening method to estimate berry phenolic substances. Methods and Results: We focused on anthocyanin and flavonol in red and white cultivars. The ANTH_RG indexwas dependent on the cultivar anthocyanin profile. In Nebbiolo, in which dihydroxylated anthocyanins prevail, ANTH_RG was 2.4 times higher than in Barbera, in which trihydroxylated anthocyanins prevail. Considering the profiles of the two cultivars at similar anthocyanin concentration and their relative in vitro absorbance, a bathochromic shift of 10 nm emerged, which can explain the different screening effect exerted by anthocyanin on chlorophyll fluorescence. As to flavanols, we propose the calibration of a new spectroscopic index, the FLAV_UV, in coloured and white berries, finding good correlation with flavonol concentration determined analytically (R2 higher than 0.7). Conclusions: Spectroscopic indices can estimate the concentration of anthocyanin and flavonol in grape berries. Significance of the Study: A calibration curve for Nebbiolo, which has a distinctive anthocyanin profile, and the calibration of a new index, the FLAV_UV, able to estimate flavonol concentration in both red and white cultivars, are described for the first time. These indices can effectively be applied for non-destructive assessment of grape flavonoid.
23
2
207
214
anthocyanin, flavonol, non-destructive measurement, TSS, Vitis vinifera
Ferrandino, Alessandra; Pagliarani, Chiara; Carlomagno, Antonio; Novello, Vittorino; Schubert, Andrea; Agati, Giovanni
File in questo prodotto:
File Dimensione Formato  
Ferrandino_et_al-2017-Australian_Journal_of_Grape_and_Wine_Research.pdf

Accesso riservato

Descrizione: pdf editoriale
Tipo di file: PDF EDITORIALE
Dimensione 1.89 MB
Formato Adobe PDF
1.89 MB Adobe PDF   Visualizza/Apri   Richiedi una copia
Manuscript_file_Ferrandino_R2_AF3 per OA Iris senza commenti.pdf

Accesso aperto

Tipo di file: POSTPRINT (VERSIONE FINALE DELL’AUTORE)
Dimensione 463.81 kB
Formato Adobe PDF
463.81 kB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2318/1634647
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 20
  • ???jsp.display-item.citation.isi??? 14
social impact