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In this work, a selection of food-grade ceramic materials (CM1, CM2) was evaluated in terms of capacity to adsorb pathogenesis-related proteins (PRPs), thus preventing protein haze in bottled white wines. The CM1 was found as the most effective sorbent material, when used in a nano-structured form (nanopowders and mesoporous films) which magnifies the specific surface available for adsorption. The material showed a high affinity and selectivity to low molecular weight proteins, thus allowing the stabilisation of white wines without altering key quality parameters. The most captivating aspect of using CM1 consisted in the possibility of producing thin and mesoporous films anchored to inert supports, to obtain composite materials that are easy to handle and safe from a food point of view. The composite material CM1 was tested in a wine flow treatment device, confirming excellent performance in terms of stabilisation. Based on the results obtained, the stabilising material and the stabilisation method proposed can be further implemented to be used in a pilot plant and exploited in the wine industry.

Ė possibile la classificazione varietale di vini ottenuti dalle principali uve rosse italiane? Questo studio indaga tale ipotesi basandosi sull’analisi di diverse componenti di base, della frazione fenolica e del colore di 110 vini rossi italiani monovarietali vendemmia 2016, prodotti con 11 differenti varietà rappresentative del territorio nazionale. La ricerca è stata condotta nell’ambito del progetto D-Wines (Diversity of Italian Wines) mirato a valorizzare la diversità di caratteristiche varietali, territoriali, chimiche e sensoriali che distingue il patrimonio enologico italiano.

Come descrivere l’astringenza di alcuni tra i principali vini rossi italiani? Quali caratteristiche e diversità presentano? Tali aspetti vengono analizzati in questo studio sensoriale che ha sviluppato i profili d’astringenza di 11 vini rossi italiani mono-varietali. La ricerca è stata condotta nell’ambito del progetto D-Wines (Diversity of Italian Wines) mirato a valorizzare la diversità di caratteristiche varietali, territoriali, chimiche e sensoriali che distingue il patrimonio enologico italiano.

Although the mechanisms of astringency perception have been partly elucidated, there is still a lack of understanding about factors and phenomena modulating this complex sensation, in relation to wine composition. In spite of their richness in tannins, some Italian grape varieties give appreciated wines with pleasant astringency. Exploiting the wide diversity of Italian red wines, we investigated if/how olfactory stimuli can modulate the perception of astringency. The sampling was made within the D-Wines (Diversity of Italian Wines) project finalized to get a wide multi-parametric dataset about Italian wines. Fourteen wine experts evaluated 112 mono-varietal red wines (2016): 19 Sangiovese; 13 Nebbiolo; 11 Primitivo and Teroldego; 10 Aglianico, Raboso and Sagrantino; 9 Montepulciano and Cannonau; 7 Corvina; 3 Nerello Mascalese. Assessors sorted and labelled the samples according to their similarities in terms of astringency sub-qualities. Data analysis (AHC, PCA, DA, MDS) allowed the selection (within and among varieties) of wines representative of diverse astringency features: particulate, velvet, complex, drying, harsh, unripe. The selected wines were deodorized (treatment in ultrasound bath followed by rotary evaporator and VOCs elimination checked by SPME-GC-MS) and reconstituted with appropriate amounts of water and ethanol. The impact of olfactory stimuli was investigated by two approaches: 1) the sorting procedure was repeated on the deodorized-reconstituted wines and results were compared to those obtained on the corresponding whole original wines; 2) the astringency sub-qualities of the deodorized-reconstituted wines were rated without and under olfactory stimulation of assessors by Direct-GC-Sniffing of VOCs isolated from the wines. Wines were chemically analyzed. Preliminary results suggest a significant impact of olfactory cues on the sensory perception of astringency sub-qualities. The study aims to provide further insight into factors modulating astringency perception and the outcomes will help in the management of the sensory consistency, optimal quality and attractiveness of Italian red wines.

This paper presents the application of the main spectroscopic techniques, including near infrared (NIR), mid-infrared (MIR) and traditional ultraviolet (UV) and visible (Vis) wavelengths, coupled with chemometric methods, to analyze grape and wine composition. In particular, IR spectroscopic techniques have the potential to shorten the analytical procedure for the simultaneous measurement of selected grape and wine components with minimal sample preparation and reagent consumption. IR spectra show specific fingerprint-like patterns that are useful for quantification (and discrimination) purposes, including both primary and secondary grape and wine metabolites, mostly suited for process monitoring, quality control, and authenticity assessment. The current state of development related to grape and wine chemistry, sensory analysis and emerging applications are discussed herein with emphasis on quantification tasks.

The chemistry of red wine color is a complex topic that is of great interest for winemaking. Improved or innovative methods of analysis are required for research and quality control. Several techniques are currently available to analyze grape and wine color, including high performance liquid chromatography and ultraviolet, visible, near-infrared, and mid-infrared spectroscopy. In particular, Fouriertransform infrared spectroscopy combined with chemometrics is well suited for correlating the spectral response of a sample to its compositional profile, and represents a valid alternative to the standard UV–vis technique. This short review focuses on the application of spectroscopy for the analysis of grape and wine color components and the contribution of spectral preprocessing to improve the multivariate calibration.

While red wine phenolics have been extensively studied, polysaccharides and proteins have not received the same level of attention, especially when considering Italian wines. In this study, for the first time, quantitative and qualitative data on the macromolecular (proteins and polysaccharides) and tannin composition of 110 monovarietal red wines from 11 of the most important Italian grape varieties are reported. The winemaking did not include any filtration, oak contact, fining treatments, or ageing on yeast lees. Results highlighted a great inter- and intra- varietal diversity. The protein content ranged between 0 and 159 mg/L, polysaccharides between 211 and 1081 mg/L and total tannins between 171 and 3746 mg/L, with averages of 41 mg/L, 497 mg/L and 1687 mg/L, respectively. Six varieties with protein content representative of the variability observed were selected and submitted to electrophoresis. Within each variety, the SDS-PAGE mobility of protein-tannin complexes was similar but showed two distinct patterns for wines of different varieties (higher mobility for Corvina, Teroldego and Raboso Piave, lower mobility for Nebbiolo, Aglianico, Cannonau), suggesting that the Italian monovarietal wines can be diverse also in their colloidal-forming structures. This can be explained by looking at the different percentages of protein-reactive tannins (TBSA) on the total tannin content (TMCP), which is a varietal characteristic.

An extensive survey was conducted on 110 Italian monovarietal red wines from a single vintage to determine their standard compositional, color, and phenolic characteristics, analysing more than 35 parameters evaluated through methods commonly used in the wine industry. ‘Primitivo’ achieved the highest average alcohol strength (15.4% v/v) and dry extract values, while ‘Cannonau’ showed the lowest total acidity. ‘Corvina’ had the lowest phenolic content (1065 mg/L by Folin-Ciocalteu assay), remarkably different from the highest found in ‘Sagrantino’ (3578 mg/L), the latter being also the richest variety in both proanthocyanidins and vanillin-reactive flavanols. ‘Teroldego’ wines were the richest in both total and monomeric anthocyanins (702 and 315 mg/L, respectively), followed by ‘Aglianico’ and ‘Raboso Piave’, while ‘Corvina’, ‘Nebbiolo’, and ‘Nerello Mascalese’ were the poorest. ‘Montepulciano’ and ‘Sangiovese’ showed intermediate values for the majority of the parameters analyzed. A multivariate PCA-DA approach allowed achieving both a classification of the different wines as well as the discrimination of ‘Sangiovese’ wines produced in two regions (Emilia Romagna and Toscana) that returned a 42–66% success rate depending on the zone considered. Taking into account the number and diversity of the wines analyzed, a correlation study helped in better understanding the underlying relations between the most common and widespread analytical techniques for phenolic and color determinations.

In the presented work, daily observations of minimum and maximum temperatures and precipitation-spatially interpolated in a high-resolution grid (5 x 5 km)-were used to detect climate shifts in the viticultural appellation areas of the Emilia-Romagna (ER) region, in the periods 1961-1990 and 1986-2015. The growing season (April to October) minimum, mean, and maximum temperatures were significantly increased in the second period compared to the first over the majority of the ER. Precipitation did not differ significantly, with the exception of certain small northeastern areas of the ER. The detected changes affected the ER viticultural environment in several ways: (1) an increase in the number of days with maximum temperature exceeding 30 degrees C, which can induce plant stress; (2) changes in starting and ending dates of the climatologically defined growing season, dates of the first fall frost and the last spring frost, and length of the frost-free period; (3) shifts of most vineyard areas from 'Region 2/Region 3' to 'Region 3/Region 4' (according to the Winkler Index); (4) shifts of the majority of the grape-producing zones from 'temperate/warm temperate' to 'warm temperate/warm' (according to the Huglin Index); (5) de creased availability of soil water, which is necessary for grapevine development.