A multivariate approach to explore the volatolomic and sensory profiles of craft Italian Grape Ale beers produced with novel Saccharomyces cerevisiae strains

Abstract

This study investigated the influence of three Saccharomyces cerevisiae strains, selected from different matrices - CHE-3 (cherry), P4 (sourdough) and TA4-10 (grape must) - on characteristics of Italian Grape Ale (IGA) beers obtained at microbrewery scale. A multidisciplinary approach, combining results from analysis of chemical, volatile and organoleptic profiles of the beers, was adopted to underline the relationships between yeast starter and the quality of final products. Detection volatile organic compounds (VOCs) by Gas-Chromatography coupled with Mass Spectrometry (GC-MS) after extraction carried out by head-space micro-extraction (HS-SPME) revealed that the beer obtained by P4 strain differed from the others for its higher concentrations of esters, alcohols, and terpenes as confirmed by PCA (principal component analysis) and Cluster heatmap. Furthermore, sensorial analysis and consumer test showed that this sample differed from others by more pronounced notes of “fruity smell and floral” and “olfactory finesse,” and it was the most appreciated beer for smell, taste, and overall quality. Conversely, CHE-3 was the sample with the lowest concentrations of the identified volatiles and, together TA4-10, showed the highest scores for smoked, yeast, malt, and hop notes. As far as we know, these are the first results on the application of indigenous S. cerevisiae strains in the production of craft IGA beers analyzed through a complex multivariate approach.

Unveiling the transformations in phytochemicals and grape features: a thorough examination of 'Italia' and 'Bronx Seedless' cultivars throughout multiple berry development stages

“…By visually grouping similar samples based on the concentrations of phytochemical components, heatmaps helped identify clusters of samples that share similar compositional characteristics. In support of the utilization of hierarchical clustering heatmaps in exploring complex datasets and PCA, Pietrafesa et al [30] Kaya [31] a emphasized the importance of these methods in their study of multivariate analysis of phytochemical data in plant sciences. Additionally, our PCA and Heatmap results are consistent with previous research reports [32,33].…”

Sourdough Yeast Strains Exhibit Thermal Tolerance, High Fermentative Performance, and a Distinctive Aromatic Profile in Beer Wort

“…Indeed, several studies have reported that S. cerevisiae baker's yeast strains can be employed to ferment brewer's wort [7,[14][15][16][17] and are typically used to brew common Eastern European beers like kvass [18] and Finland's sahti [19,20]. Sourdough cultures are also interesting reservoirs of maltose-negative yeasts for low-alcohol beer brewing [21], fruit beers [22] and craft beers with potential healthy added value [23][24][25][26]. Beers obtained using sourdough strains are also characterized by aromatic differences that are in consonance with their specific metabolic features, which appear to promote the synthesis of volatile compounds [14], in particular esters [1], instead of the fuse alcohols more abundant in brewing yeasts [27].…”

Unmalted Cereals, Oenological Yeasts, and In-Bottle Sugar Addition as Synergic Strategies to Enhance the Quality of Craft Beers

“…Although there is a large amount of literature concerning the priming composition during the refermentation step [11][12][13], poorly or not investigated at all is the quantity of sugar added for refermentation and its effects on physico-chemical and organoleptic characteristics of beers.…”