Investigation of intraregional variation, grape amino acids, and pre-fermentation freezing on varietal thiols and their precursors for Vitis vinifera Sauvignon blanc. (15th October 2019)

• Record Type: Journal Article
• Authors: Chen, Liang; Capone, Dimitra L.; Nicholson, Emily L.; Jeffery, David W.
• Is Part Of: Food chemistry. Volume 295(2019)
• Page Start: 637
• Page End: 645
• Publication Date: 2019-10-15
• Subjects: 3-SH 3-sulfanylhexan-1-ol -- 3-SHA 3-sulfanylhexyl acetate -- 4-MSP 4-methyl-4-sulfanylpentan-2-one -- ANOVA analysis of variance -- Cys-3-SH 3-S-cysteinylhexan-1-ol -- DTDP 4, 4′-dithiodipyridine -- GABA γ-aminobutyric acid -- GI Geographical Indication -- Glut-3-SH 3-S-glutathionylhexan-1-ol -- IS internal standard -- PC principal component -- PCA principal component analysis -- PFF pre-fermentation freezing -- SD standard deviation -- SIDA stable isotope dilution assay -- SPE solid-phase extraction -- TA titratable acidity -- TSS total soluble solids; 3-Sulfanylhexan-1-ol -- 3-Sulfanylhexyl acetate -- 4-Methyl-4-sulfanylpentan-2-one -- Aroma enhancement -- Wine aroma -- Winemaking; 3-Sulfanylhexan-1-ol (PubChem CID 521348) -- 3-Sulfanylhexyl acetate (PubChem CID 518810) -- 4-Methyl-4-sulfanylpentan-2-one (PubChem CID 88290) -- Arginine (PubChem CID 6322) -- Proline (PubChem CID 145742) -- Glutamic acid (PubChem CID 33032) -- γ-Aminobutyric acid (PubChem CID 119) -- α-Alanine (PubChem CID 5950); Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2019.05.126
• Languages: English
• ISSNs: 0308-8146

Abstract

Abstract: Sauvignon blanc grape samples (n = 21) from across a single Geographical Indication of South Australia were analysed for thiol precursors and amino acids, and fermented in an identical laboratory-scale fermentation trial to investigate the intraregional pattern of varietal thiols in the wines. Precursors and thiols exhibited obvious intraregional diversity, and notably, stronger correlations were observed between a number of amino acids and thiol precursors (especially with glutamic acid, r ≤ −0.73) rather than free thiols. Additionally, pre-fermentation freezing (−20 °C, 1 month) was applied to five selected fresh grape samples and their juices, followed by identical fermentation. In comparison to wines from fresh grapes or frozen juices, significant elevation of varietal thiols (up to 10-fold) occurred in the wines derived from frozen grapes, with parallel increases of precursors (up to 19-fold) in juices from frozen berries. These novel results may lead to new strategies for thiol enhancement during winemaking.