In this research, the chemical characterization of fixed and volatile compounds of two different tannins in aqueous solution (Pratiko® L-Harvest and L-Fruit) extracted from oak wood, has been ...studied. The influence of the above tannins, at different concentrations, on the alcoholic fermentation kinetics and on the composition and sensorial characteristics of a white wine were then evaluated. The wines added tannins in aqueous solution compared to control wines showed significant differences in fixed compounds (colloids, polyphenols and ellagitannins) and volatile compounds (phenolic aldehydes, volatile phenols, furanic and piranic compounds). The differences of aqueous solution tannins extracted from oak wood were partly due to the drying/maturing and roasting methods used in barrel production. Alcoholic fermentation was partially facilitated by the addition of tannins in aqueous solution. The wines obtained showed a higher content of ethyl esters of medium-chain fatty acids (from 22 to 31%) and, in some cases, higher acetate alcohols (from 15 to 28%), relevant to the olfactory sensations provided to the wines. The tannins added to the must before fermentation also made it possible to obtain an additional supply of polyphenols (from 25 to 85%) able to induce more complex sensory profiles in the wines, with increased persistent taste notes.
Biochar is a porous material obtained by biomass thermal degradation in oxygen-starved conditions. It is nowadays applied in many fields. For instance, it is used to synthesize new materials for ...environmental remediation, catalysis, animal feeding, adsorbent for smells, etc. In the last decades, biochar has been applied also to soils due to its beneficial effects on soil structure, pH, soil organic carbon content, and stability, and, therefore, soil fertility. In addition, this carbonaceous material shows high chemical stability. Once applied to soil it maintains its nature for centuries. Consequently, it can be considered a sink to store atmospheric carbon dioxide in soils, thereby mitigating the effects of global climatic changes. The literature contains plenty of papers dealing with biochar’s environmental effects. However, a discrepancy exists between studies dealing with biochar applications and those dealing with the physical-chemistry behind biochar behavior. On the one hand, the impression is that most of the papers where biochar is tested in soils are based on trial-and-error procedures. Sometimes these give positive results, sometimes not. Consequently, it appears that the scientific world is divided into two factions: either supporters or detractors. On the other hand, studies dealing with biochar’s physical-chemistry do not appear helpful in settling the factions’ problem. This review paper aims at collecting all the information on physical-chemistry of biochar and to use it to explain biochar’s role in different fields of application.
In this study, 1H-NMR spectroscopy coupled with chemometrics was applied to study the wine metabolome and to classify wines according to different grape varieties and different terroirs. By obtaining ...the metabolomic fingerprinting and profiling of the wines, it was possible to assess the metabolic biomarkers leading the classification (i.e., phenolic compounds, aroma compounds, amino acids, and organic acids). Moreover, information about the influence of the soil in shaping wine metabolome was obtained. For instance, the relationship between the soil texture and the content of amino acids and organic acids in wines was highlighted. The analysis conducted in this study allowed extraction of relevant spectral information not only from the most populated and concentrated spectral areas (e.g., aliphatic and carbinolic areas), but also from crowded spectral areas held by lowly concentrated compounds (i.e., polyphenols). This may be due to a successful combination between the parameters used for data reduction, preprocessing and elaboration. The metabolomic fingerprinting also allowed exploration of the H-bonds network inside the wines, which affects both gustatory and olfactory perceptions, by modulating the way how solutes interact with the human sensory receptors. These findings may have important implications in the context of food traceability and quality control, providing information about the chemical composition and biomolecular markers from a holistic point of view.
A dehydration experiment was carried out on
L.
Muscat of Alexandria (synonym Zibibbo) following the process for the production of renowned special dessert wines produced on Pantelleria island ...(Sicily, Italy). Harvested berries were pre-treated in a sodium hydroxide dipping solution (45 g/L, dipped for 185 s, 25 °C) to accelerate the drying process, rinsed, and dehydrated in simulated conditions (relative humidity 30%, 30 °C temperature, air speed 0.9 m/s). Three dehydration levels were achieved, corresponding to "
", "
", and "
" stages (35%, 50%, and 65% of weight loss, respectively) of the Pantelleria denomination of origin (DOC). Grape skin mechanical properties, technological parameters, phenolics, and aroma profile varied considerably during dehydration. The most important aroma compounds for their olfactory impact, such as linalool, geraniol, nerol, and citronellol, especially in glycosylated forms, significantly increased in dried grapes compared to fresh ones, even if aroma profile modification occurred. A decrease in break skin force could have induced higher release of flavonoids. The findings showed relevant changes, allowing winemakers to better select the ratio of fresh and dehydrated grapes in the function of the final desired wine.
In this study, the effects of the main soil chemical-physical parameters (i.e., texture, pH, total carbonates, organic matter, cation exchange capacity, electric conductivity, and mineral ...composition) on some of the most important oenological parameters (e.g., phenolics and volatile organic compounds) of red wines obtained from grapes of Vitis vinifera L. cv Nero d’Avola were studied. The study was conducted by means of a chromatography-based targeted metabolomic approach.
The obtained results highlighted that the soil influenced both the phenolic and the volatile composition of the resulting wines. Wines phenolic composition appeared to be influenced by the texture and the cation exchange capacity, that are linked to the modulation of water and nutrient dynamics in soils.
The volatile organic composition of the wines was mostly influenced by the cation exchange capacity and the organic matter, both related to soil fertility.
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•The soil effect on the phenolic and volatile composition of red wines was studied.•The study was conducted by means of a chromatography-based untargeted approach.•Wine phenolic composition was influenced by soil texture and cation exchange capacity.•Volatile composition was also influenced by soil organic matter.
The aim of this study was to investigate the fermentation performance of a
Saccharomyces cerevisiae
(
Meyen ex E.C. Hansen
) yeast strain with high alcoholigenous power during the vinification of
...Grillo
and
Nero d’Avola
musts with high sugar concentration. The effects of such fermentations, conducted by means of FR-RS8 yeast strain, were evaluated through analyzing the fermentation kinetics, the chemical–physical parameters of musts and wines, and the volatile organic composition of the final wines. The sensory profiles of the obtained wines were also evaluated. Results highlighted that the FR-RS8
Saccharomyces cerevisiae
yeast strain showed a great fermentation activity, suggesting an appreciable capability to overcome osmotic stress deriving from high sugar concentration musts, while the production of volatile acidity was moderate. Wines fermented by FR-RS8 yeast strain showed low content of higher alcohols, great amount of fermentation esters, and high content of free terpenes in both
Grillo
and
Nero d’Avola
wines. Sensory analysis highlighted that the aforementioned wines were very scented, complex, and structured, with good olfactory and gustatory persistence.
In this study, the soil effect on the micro-component composition of Nero d’Avola wines obtained from different locations was investigated through 1H NMR-based metabolomics. Two different approaches ...were applied: the targeted (TA) and the non-targeted one (NTA). The former differentiated the wines by profiling (i.e., by identifying and quantifying) a number of different metabolites. The latter provided wine fingerprinting by processing the entire spectra with multivariate statistical analysis. NTA also allowed investigation of the hydrogen bond network inside wines via the analysis of 1H NMR chemical shift dispersions. Results showed that the differences among wines were due not only to the concentrations of various analytes but also to the characteristics of the H-bond network where different solutes were involved. The H-bond network affects both gustatory and olfactory perceptions by modulating the way how solutes interact with the human sensorial receptors. Moreover, the aforementioned H-bond network is also related to the soil properties from which the grapes were taken. Therefore, the present study can be considered a good attempt to investigate terroir, i.e., the relationship between wine quality and soil characteristics.
In this study, the soil effect on the micro-component composition of
wines obtained from different locations was investigated through
H NMR-based metabolomics. Two different approaches were applied: ...the targeted (TA) and the non-targeted one (NTA). The former differentiated the wines by
(i.e., by identifying and quantifying) a number of different metabolites. The latter provided wine
by processing the entire spectra with multivariate statistical analysis. NTA also allowed investigation of the hydrogen bond network inside wines via the analysis of
H NMR chemical shift dispersions. Results showed that the differences among wines were due not only to the concentrations of various analytes but also to the characteristics of the H-bond network where different solutes were involved. The H-bond network affects both gustatory and olfactory perceptions by modulating the way how solutes interact with the human sensorial receptors. Moreover, the aforementioned H-bond network is also related to the soil properties from which the grapes were taken. Therefore, the present study can be considered a good attempt to investigate
, i.e., the relationship between wine quality and soil characteristics.
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•Proanthocyanidins profiles of Nero d’Avola and Grillo wines were determined.•Soil chemical-physical parameters affect the proanthocyanidins composition of the wines.•Soil parameters ...related to nutrient dynamics affect tannin composition in Nero d’Avola red wines.•Soil parameters related to water dynamics affect tannin composition in Grillo white wines.
In this study, the effects of the main soil chemical-physical parameters (i.e. texture, pH, total carbonates, cation exchange capacity, electric conductivity, organic matter and mineral endowment) on proanthocyanidin composition of Nero d’Avola red wines and Grillo white wines were investigated. Monomer proanthocyanidins (i.e. (+)-catechin and (-)-epicatechin) and oligomer proanthocyanidins (i.e. B1, B2, B3 and B4 dimers and C1 trimer), as well as proanthocyanidins subunit composition, percentage of galloylation, percentage of prodelphinidins and mean degree of polymerization, were studied for each wine. Results highlighted that the proanthocyanidins composition of both red and white wines is greatly affected by soil. In particular, the proanthocyanidins composition of Nero d’Avola red wines appeared to be affected by the soil physical–chemical parameters related to nutrients dynamics (CEC, EC, pH, organic matter, mineral endowment), whereas the proanthocyanidins composition of Grillo white wines was mainly influenced by the soil texture, that modulates soil water dynamics.
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