# Influence of Oak Chips and Oak Barrel Ageing on Volatile Profile in Chardonnay Wine of Romania
## 3 Results
### Multivariate Analysis  
Figure 1 shows the chemical analysis results of the Chardonnay wines overlaid over the studied variants, with the wines projected on to that space. According to PLSR analysis, the distance between the variable and the center of the circle shows the interpretive degree of the principal components to the variable. The PLSR was established to determine the influence of methods and duration of ageing on volatile compounds.  
Figure 1: Partial least squares regression (PLSR) analysis, chemical data and the correlation of Chardonnay wines between ageing method and time (t1, chemical components of control wine; t2, chemical components released from wood). CW, N1M, N2M, N3M, L1M, L2M, L3M, BAR1M, BAR2M and BAR3M are the abbreviations for 10 variants of Chardonnay (CW—control wine, N—non-toasted chips, L—light toasted chips, BAR—non-toasted barrel; 1M, 2M and 3M—number of months of ageing). MA1 (iso-butanol), MA2 (isopently), MA3 (2-phenylethyl), mA1 (1-hexanol), mA2 (4-methyl-1 pentanol), mA3 (E-3-hexenol), mA4 (Z-3-hexenol), mA5 (2-nonanol), mA6 (1-heptanol), mA7 (2,3-butanediol), mA8 (3-methylthio-1-propanol), mA9 (benzyl-alcohol), T1 (linalol), T2 (terpine), T3 (trans-geranilon), FA1 (iso-butyric acid), FA2 (hexanoic acid), FA3 (isovaleric acid), FA4 (octanoic acid), FA5 (decanoic acid), FA6 (malic acid), FA7 (5-oxotetrahydofuran-2-carboxilic acid), FA8 (2-oxoxapidic), FA9 (lactic acid), ESI (N-amyl acetate), ES2 (hexyl-acetate), ES3 (ethyl hexanoate), ES4 (ethyl lactate), ES5 (ethyl octanoate), ES6 (phenethyl acetate), ES7 (diethyl malate), ES78 (diethyl succinate), ES9 (tri-methylene acetate), ES10 (ethyl-4-hydroxybutanoate), L1 (butylrolactone), L2 (pantolactone), L3 (3,4-dimethyl-2(5)-furanone), VP1 (\(p\)-vinyl guaiacol), VP2 (methyl-hydroxycinamate), VP3 (acetovanillone), VP4 (2,3-hydroxybenzofuran), VP5 (vanillin).  
In Figure 1, the volatile compounds of the control wine can be used to distinguish the aroma compounds of the aged wines. Control wine (unaged) is well related to alcohols such as iso-butanol (MA1), 2-nonanol (mA5), and to the terpenes: linalool (T1), terpineol (T2) and trans-geranoid (T3). Esters like hexyl-acetate (ES2), fatty acids like malic acids (FA6) and lactones like 2,4-dimethyl-2(5)-furanone were also related to the control Chardonnay wine. Those compounds are specific for fresh wines. The wines that pass through the maturation process are related to the esters, fatty acids, lactones and volatile phenols [36,37]. As can be seen from Figure 1, the wines aged in non-toasted medium (chips and barrel) appear as grouped against the wines aged with light toasted chips. This finding is similar with other research by [PERSON] et al. [13], for Muscat Ottonel wines. The non-toasted barrel ageing is correlated with lactones that came from untreated wood--butyrolactone (L1) and pantolactone (L2). The non-toasted medium is also related to esters such as ethyl lactate (ES4), ethyl caproate (ES3), and carboxylic acid, as lactic acid (FA9), octanoic acid (FA4) and isovaleric acid (FA3). The majority of volatile phenols quantified in this research, came from the thermal treatment of wood and are correlated with wines aged with light-toasted chips. In a study, [PERSON] et al. [38], stated that vanillin (VP5), \(p\)-vinyl guaiacol (VP1) and acetovanillone (VP3) are volatile phenols which come from the thermal degradation of wood.