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Highlights • The presence/absence of oak wood during MLF was evaluated for Chardonnay wine. • Three different barrel toastings were considered during MLF and/or wine ageing. • Aroma profile was more impacted by MLF-container and ellagitannins by toasting. • Use of barrels as MLF-containers does not change perception of Chardonnay character. • Higher woody aroma content of MLF-barrel wines does not mask fruity/floral notes. Abstract Malolactic fermentation (MLF) and oak barrels aging are two oenological processes which modify wine composition and sensory characteristics. The effect of MLF-container (stainless steel tanks, barrels) and barrel toasting (T1, T2, T3) on ellagitannin concentration, volatile composition and sensory attributes of Chardonnay wines was evaluated. Barrel toasting had higher impact on ellagitannin content than MLF-container. When comparing both MLF-modalities, barrel-fermented wines exhibited greater amounts of vanillin and whiskey-lactones but lower concentrations of fruity aroma compounds. Regarding sensory analysis, greater citrus and floral aromas were perceived for MLF-tank wines, and higher nuts aroma for MLF-barrel wines. Using barrels as MLF-containers i) did not change the aroma perception defining Chardonnay character (peach, apricot and gun flint); ii) did not impact the aromatic intensity and persistence, sweetness, acidity, mouthfeel volume and/or bitterness; and iii) did not confer significantly higher overall woody aromas which might mask fruity, floral and mineral (gun flint) character. [ABSTRACT FROM AUTHOR]

Ellagitannins and aromatic compounds evolution in Cabernet Sauvignon wines macerated in oak barrels for a year was studied. Identical barrels with different toastings (medium toasting, medium toasting with watering, Noisette) were used in French, Italian and USA cellars. Ellagitannins increased by 84–96% with aging time, as did woody volatiles, by 86–91% in French wines and 23–35% in Italian wines, while fruity aroma compounds declined by 50–57% in the French and Italian wines over a 12-months period. Nevertheless, other behaviors and different kinetics rates for these compounds were observed depending on barrel toasting, wine matrix and their interactions. Perceived overall woody intensity was closely related to trans -whiskey lactone, guaiacol and vanillin, whereas astringency and bitterness were significantly linked to ellagitannins ( p < 0.05). This is the first study that evaluates the toasting effect on wines from different countries matured in the same oak barrels. [ABSTRACT FROM AUTHOR]

The effects of five processing forms on the content of phenolic compounds, antioxidant capacity, and saponin content in quinoa grains were evaluated. The processes included washing, washing followed by hydration, cooking (with or without pressure), and toasting. The highest content of phenolic compounds was obtained after cooking under pressure; however, these compounds also increased with grain washing. The toasting process caused the greatest loss. The antioxidant capacity of the grains was similarly affected by the processing techniques. According to the amount of saponins, the grains were classified as bitter. Washing caused a reduction in these compounds, but the levels remained unchanged after cooking (with and without) pressure and toasting; however, they significantly increased after hydration. Cooking, especially with pressure, had greater effects than the other processes, and potentiated the functional properties of quinoa grains. [ABSTRACT FROM AUTHOR]

Low molecular weight phenolic compounds (LMWPC), including non-volatile and volatile, of Airén and Moscatel vine-shoot cultivars waste submitted to different toasting conditions (light, 180°/15 min; medium, 180°/30 min; high 180°/45 min) were studied in order to exploit them with oenological purposes. The LMWPC differences were mainly due to the toasting times rather than vine-shoot variety. In non-volatile LMWPC fraction, flavanols and almost all phenolic acids decreased by toasting. The presence of trans -resveratrol has a special relevance at light toasting: 14 times more concentrated in Airén and 6 times in Moscatel vine-shoots, than their respective non-toasted samples. The volatile LMWPC showed a significant increment with toasting, being vanillin the one with the highest difference respect to non-toasted samples at high conditions: more than 15 times in Airén and 11 in Moscatel. Although toasting reduced some LMWPC, particular characteristics of these vine-shoots must be taken into account when considering its future use. [ABSTRACT FROM AUTHOR]

Heat stabilization of wheat bran aims at inactivation of enzymes which may cause rancidity and processability issues. Such treatments may however cause additional unanticipated phenomena which may affect wheat bran technological properties. In this work, the impact of toasting on wheat bran hydration capacity and hydration kinetics was studied. Hydration properties were assessed using the Enslin–Neff and drainage centrifugation water retention capacity methods, thermogravimetric analysis and contact angle goniometry, next to more traditional methods. While equilibrium hydration properties of bran were not affected by the heat treatment, the rate at which the heat treated bran hydrated was, however, very significantly reduced compared to the untreated bran. This phenomenon was found to originate from the formation of a lipid coating during the treatment rendering the bran surface hydrophobic. These insights help to understand and partially account for the modified processability of heat treated bran in food applications. [ABSTRACT FROM AUTHOR]

Abstract: Red wine from the Greek grape cultivar Aghiorghitiko, was aged in stainless steel with and without wood chips toasted to different degrees (heavily, medium, lightly) and in a 225L American standard oak barrel for 32 days. Headspace concentrations of four wood-derived congeners (furfural, guaiacol, cis and trans oak lactones) were determined over this period after which the wines were bottled, stored and subjected to sensory descriptive analyses. Of the 36 attributes for appearance, aroma and oral characters, 14 were significant in univariate analyses and differentiated wines in a multivariate (principal component analysis) product space explaining 72% variance in two factors. Wines from medium toast wood chips scored highest for woody, vegetative and smoky aromas and flavours but also for bitter taste and astringent mouthfeel and after 14 days had the highest headspace concentrations of furfural and cis oak lactone. Wood-related notes were ranked from heavily and lightly toasted chips, barrel and steel control. [Copyright &y& Elsevier]

Abstract: Volatile and semi-volatile compounds of French and American oak wood used in wine and spirits ageing were extracted by an Accelerated Solvent Extractor (ASE) and analysed by gas chromatography–mass spectrometry. More than 90 compounds were isolated, characterised and quantified after being separated on two chromatographic columns with distinct polarity. The main oak wood components were quantitatively determined by using standard reference compounds. In addition, a number of compounds, mainly guaiacol and syringol derivatives, were detected and characterised. In particular, 10 compounds were tentatively identified as lignin dimers derivatives, whose presence in oak wood chips or barrels for wine and spirits ageing had not been previously described. Several of the characterised compounds enabled a distinction to be drawn between medium and high toasted wood chips, independently of their geographical origin. [Copyright &y& Elsevier]

• Q. petraea volatile composition is related to the oxygen transfer rate (OTR) • Toasting process affect differently to staves from Q. petraea with low or high OTR. • Low-OTR staves showed higher content in phenolic aldehydes and furanic compounds. • High-OTR staves had higher content in some volatile phenols, aldehydes and lactones. • Red wines aged for three months in high-OTR and low-OTR barrels were different. The compounds that the wood releases to the wine and the oxygen transmission rate (OTR) of the barrel define the final wine. The new possibility of choosing the OTR of the barrel allows the winemaker to globally control the ageing process. The aim of this work was to study the volatile composition of woods classified according to their OTR, which are used to build barrels for wine ageing. The results showed that volatile composition differs depending on wood OTR and the temperature reached during toasting. On the toasted side of the stave in contact with the wine, low OTR wood had a statistically higher content in furan compounds (5-hydroxymethylfurfural, furfural and 5-methylfurfural), acetovanillone and phenolic aldehydes (vanillin and syringaldehyde), while 4-ethylguaiacol and trans -β-methyl-γ-octalactone were significantly higher in staves with a high OTR. The same red wine aged first for three months in high and low oxygenation barrels presents different characteristics. [ABSTRACT FROM AUTHOR]