Cluster shading modifies amino acids in grape (Vitis vinifera L.) berries in a genotype- and tissue-dependent manner

Le Guan (1, 2) , Benhong Wu (2) , Ghislaine Hilbert (1) , Shaohua Li (2) , Eric Gomes (1) , Serge Delrot (1) , Zhanwu Dai (1)

1 UMR EGFV - Ecophysiologie et Génomique Fonctionnelle de la Vigne
2 Beijing Key Laboratory of Grape Science and Enology/CAS Key Laboratory of Plant Resource

Amino acid composition of the grape berry at harvest is important for wine making. The present study investigates the complex interplay between tissue, cultivar and light conditions that determine berry amino acid content. Twenty amino acids were assessed in the berry skin and pulp of two grape cultivars (Gamay Noir and Gamay Fréaux), grown under either light exposure or cluster shading conditions. In all samples, cluster shading significantly reduced most amino acids, except gamma-aminobutyric acid (GABA) and phenylalanine. However, the magnitude of the decrease was stronger in the skin (67.0% decrease) than in the pulp (30.4%) and stronger in cv. Gamay Noir (69.7%) than in Gamay Fréaux (30.7%). Cluster shading also significantly modified amino acid composition by decreasing the proline content while increasing the GABA content. These results are of oenological interest for shaping the amino acid composition of the must and improving wine quality.

Mots clés: teinturier; Gamay Fréaux; tissues; amino acid; shadowing (histology); Vitis vinifera; amino acids; shading

Mots clés: acide aminé; qualité du vin; baie de raisin; ombrage

Domaines: Sciences du Vivant [q-bio]

Le Guan, Benhong Wu, Ghislaine Hilbert, Shaohua Li, Eric Gomes, et al.. Cluster shading modifies amino acids in grape (Vitis vinifera L.) berries in a genotype- and tissue-dependent manner. Food Research International, 2017, 98, pp.2-9. ⟨10.1016/j.foodres.2017.01.008⟩. ⟨hal-01608726⟩