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In this study, the combined effect of partial postharvest dehydration and long-term ozone treatment was evaluated at 10 and 20% weight loss as a strategy to induce compositional changes in grape skin flavanols. Two separate trials were carried out in thermohygrometric-controlled chambers at 20 °C and 70% relative humidity. The first trial was conducted under an ozone-enriched atmosphere at 30 μL/L, whereas the second trial was performed under an air atmosphere as a control. Two red wine grape varieties were studied, Barbera and Nebbiolo (Vitis vinifera L.), for their different phenolic composition. Berry skin flavanol composition was determined by high-performance liquid chromatography after phloroglucinolysis and size-exclusion chromatography. The results showed that dehydration and ozone effects were variety-dependent. In Barbera skins, being characterized by lower proanthocyanidin contents, the two effects were significant and their combination showed interesting advantages related to lower proanthocyanidin loss as well as higher prodelphinidin and lower galloylation percentages. In Nebbiolo, skin flavanol composition was barely affected.

Grape maturity at harvest strongly affects wine quality, and therefore determining an adequate strategy for harvest date selection based on objective quality indicators is a key issue in producing high-quality and premium wines. In white wine technology, grape quality is usually assessed by chemical composition with a particular interest in volatile content and profile. In this sense, vineyard management is of primary importance together with the choice of harvest time. In fact, the basis of wine characteristics is intrinsically confined in the grape quality, and the wide diversity in white wine grape chemical composition is of major technological importance, as each cultivar requires dedicated enological adaptation of the winemaking technique.

In winemaking industry, good cleaning and sanitization practices are essential in bottle filling process to preserve quality and avoid subsequent alterations after bottling, when microbes find environment favourable for their development. Devices connected by pipelines, like wine bottling machines, are usually cleaned using Cleaning-in-Place (CIP) method, generally requiring a high consumption of water and the use of chemical cleaning detergents with a negative impact on the environment. Ozone has recently attracted attention due to its efficacy against a broad spectrum of microorganisms and its ability to clean leaving no residues on treated surfaces, protecting the environment and human health. This study aimed to investigate the impact of aqueous (3.5 mg/L for 15 and 30 min of contact time) and gaseous ozone (30 μL/L for 30 and 60 min of contact time) treatments in comparison with usual sanitizing treatment with peracetic acid (1% for 15 min of contact time) on six wine related microorganisms of oenological significance for their potential proliferation in the bottled wine. To this end, an artificially contaminated wine was used to fill rigid and flexible stainless-steel pipes and a bottling machine. The effectiveness of each treatment was evaluated using culture-dependent approach. The microorganisms showed different sensibilities to the treatments, dependent on the sanitization method used. The exposure to aqueous ozone for 30 min was the most effective treatment for pipes cleaning, followed by peracetic acid. On the other hand, when considering the bottling machine, the use of peracetic acid as sanitizing agent led to a complete removal of the cells, while aqueous ozone for a contact of 30 min was able to eliminate all microorganisms except S. cerevisiae.

Foliar treatments using two products based on Saccharomyces cerevisiae inactive dry yeast derivatives with specific formulations for white and red varieties were tested in two consecutive vintages on Vitis vinifera L. cv. Chardonnay, Cortese, and Nebbiolo grown in Piedmont (north-west Italy). The possible elicitor effect of the foliar treatment was assessed at harvest on the chemical composition and mechanical properties of grape berries. The accumulation and extractability of phenolic compounds in Nebbiolo grape skins were also studied. Wines were produced and analysed in terms of technological parameters, color characteristics, free volatile composition, and phenolic compounds. The treatments induced an +16 μm average increase in berry skin thickness, which makes the grapes more resistant to physical damages and pathogenous attacks. In Nebbiolo, this treatment enhanced the accumulation of anthocyanins (+33 mg/kg on average). However, the obtained results pointed out a vintage effect. In 2015, few significant differences between wines made from control and treated grapes were found. Instead, in 2016, Nebbiolo treated wines had a slightly worse chromatic quality as a consequence of lower contents of phenolic compounds, but they were richer in relative amounts of malvidin-3-glucoside.

Spoilage by Brettanomyces bruxellensis is a major concern for the wine industry. The negative effect of this yeast on wine quality, that is, potentially large associate economic losses and the production of phenolic off-flavors, requires application of specific control measures. We investigated the ability of ozone to control the B. bruxellensis population on treated Barbera winegrape berries, and the impact on subsequent winemaking or fermentation. To further explore the ability of ozone treatments to reduce the B. bruxellensis population, a mix of three different strains was artificially inoculated onto the surface of grape berries. Grape berries were ozone-treated either in aqueous (6 or 12 min) or gaseous form (12 or 24 hr), crushed, then fermented to evaluate the effect of these treatments on B. bruxellensis and Saccharomyces cerevisiae growth dynamics and wine composition. Microbiological analysis revealed a significant reduction in B. bruxellensis of ~2.2 log colony forming units (CFU)/mL after treatment with gaseous ozone for 24 hr. The wines produced from grape berries previously exposed to gaseous ozone for 24 hr contained the lowest levels of acetic acid. Moreover, 4-ethylphenols were detected in wines produced from grape berries treated with water (6 or 12 min), in which B. bruxellensis population reached 5.0 log CFU/mL at the end of fermentation. Molecular analysis suggested that the three tested strains had similar sensitivity to the ozone treatments applied. This study shows the first results about the ability of ozone to control the population of different B. bruxellensis strains within the same species in the same manner.

The use of mixed fermentations with Starmerella bacillaris and Saccharomyces cerevisiae is gaining attention in recent years due to their ability to modulate the metabolites production of enological interest. In the present study, four of the most popular planted red grape varieties (Cabernet sauvignon, Merlot, Pinot noir and Shiraz) were fermented using the aforementioned species and two different inoculation protocols (inoculation of S. cerevisiae after 24 and 48 h from the Starm. bacillaris inoculation), in order to evaluate their impact on the volatile composition and chromatic characteristics of wines. Analysis from chemical composition showed that titratable acidity and glycerol content exhibited marked differences among wines after fermentation. For volatile compounds, mixed fermented wines using an inoculation delay of 48 h led to reduction of volatile compounds (mainly esters). A shorter 24 h delay produced wines with higher values of color intensity than pure fermented wines. The differences observed between the inoculation protocols can be explained by the growth dynamics of both species during fermentation. These findings suggest that mixed fermentations posed a great potential in reducing metabolites which are considered negative for wine quality (mainly ethyl acetate and volatile fatty acids) and with an improvement of the chromatic profile of the wines.

In this study, we investigated the possible effect of electrolyzed water (EW), aqueous ozone (WO) and gaseous ozone (GO) on Brettanomyces bruxellensis DSM 7001 strain artificially inoculated on the grape surface and on its evolution during the subsequent, inoculated must fermentation. Culture-dependent and -independent techniques were used to evaluate the effectiveness of treatments against B. bruxellensis, as well as its presence during fermentation. Particularly, GO treatment of 24 h decreased its presence by about 2.1 Log, making it possible to reduce significantly the concentration of ethylphenols in the wine in relation to the control wine. EW and WO treatments caused less relevant reductions. The results showed that all the treatments reduced the presence of this yeast on grapes. However, in these experimental conditions it was not possible to achieve a complete removal of this undesirable yeast. Industrial relevance Brettanomyces spp. is considered a wine spoilage yeast due to its ability to produce off-flavors (described as Brett character) and high levels of acetic acid. Broad disinfectant action against microorganisms, eco-friendliness and easiness of on-site application are among the main advantages of the ozone and the electrolyzed water. This study demonstrated the antimicrobial potential of the EW, WO and GO treatments against B. bruxellensis inoculated on post-harvest grapes.

Starmerella bacillaris (synonym Candida zemplinina ) is a non- Saccharomyces yeast that has been proposed as a co-inoculant of selected Saccharomyces cerevisiae strains in mixed culture fermentations to enhance the analytical composition of the wines. In order to acquire further knowledge on the metabolic interactions between these two species, in this study we investigated the impact of oxygen addition and combination of Starm. bacillaris with S. cerevisiae strains on the microbial growth and metabolite production. Fermentations were carried out under two different conditions of oxygen availability. Oxygen availability and strain combination clearly influenced the population dynamics throughout the fermentation. Oxygen concentration increased the survival time of Starm. bacillaris and decreased the growth rate of S. cerevisiae strains in mixed culture fermentations, whereas it did not affect the growth of the latter in pure culture fermentations. This study reveals new knowledge about the influence of oxygen availability on the successional evolution of yeast species during wine fermentation.

Postharvest withering of grapes strongly affects the content and extractability of phenolic compounds in the production of sfursat, fortified and passito wines. This work evaluated the effectiveness of enzymes applied individually and/or in multi-enzyme blends, on the extraction of anthocyanins, oligomeric flavanols and polymeric flavanols from withered grape skins during simulated maceration. The study was performed on Vitis vinifera L. cv. Nebbiolo and Barbera because of their different skin phenolic profile and cell wall composition. Our findings highlight that the relationship between skin mechanical properties (berry skin break force and energy) and extraction yield of phenolic compounds is variety dependent. Significant correlations were found between the skin softening associated with cell wall degradation and the extraction of anthocyanins and flavanols in Nebbiolo, for which polygalacturonase, individually or in multi-enzyme blends, plays an important role. In Barbera, the extractability of phenolic compounds was not affected by the presence of exogenous enzymes.

Background and Aims The aim of this work was to assess and compare the chemical composition and colour characteristics of Barbera red wines obtained after partial alcohol reduction using three promising methodologies for implementation at the industrial level. Methods and Results Alcohol reduction was achieved by: (i) pre-fermentation addition of liquid derived from grape must (reverse osmosis by-product); (ii) mixed fermentations with strains of Starmerella bacillaris and Saccharomyces cerevisiae; and (iii) dealcoholisation of wine post-fermentation with a polypropylene membrane. The microbiological approach enabled the production of wines with a slightly lower alcohol concentration (−0.2 to −0.3% v/v), while facilitating the release of anthocyanin and some esters of fatty acids (ethyl hexanoate and ethyl dodecanoate) that could contribute positively to wine aroma with pleasant nuances. The low impact of the partial replacement of grape juice on the chemical composition and chromatic characteristics of Barbera wines makes this technique a good option for reducing the ethanol concentration by up to 1.0–2.0% v/v. In contrast, the use of a polypropylene membrane influenced negatively the composition of red wines by reducing significantly the concentration of esters (−60%) and anthocyanin (−17%), independently of the dealcoholisation level (up to −2% v/v). Conclusions The alcohol reduction strategies can greatly influence the volatile and phenolic composition of the wine. The choice of either a technological or microbiological approach in the wine industry is dependent on the alcohol reduction required. Significance of the Study This is the first comparative study of three strategies to reduce the alcohol concentration on the same batch of must/wine.

Recently the use of ozone as sanitizing agent has been proposed on winegrapes in order to control mycobiota after harvest. The aim of this work was to investigate possible indirect physico-chemical effects of ozone treatment on berry skin phenolic composition and extractability. Vitis vinifera L. cv Nebbiolo and Barbera, chosen for their different anthocyanin profiles, were post-harvest treated for 24 and 72 h with gaseous ozone (30 μL/L). Skin anthocyanin and flavanol extractability was assessed during maceration (6, 24, 48, 96, 168 and 240 h) using a wine-like solution. In our experimental conditions, ozone did not affect significantly the final extraction yield of anthocyanins (TA), proanthocyanidins (PRO), and flavanols reactive to vanillin (FRV) in Barbera, although TA and FRV extractabilities were higher in control samples than in ozone-treated samples during the first stages of maceration. In Nebbiolo, the final TA extraction yield was positively influenced by the ozone treatment (68.6, 64.2, and 59.9% for 24 h ozone-treated berries, 72 h ozone-treated berries and control samples, respectively). Final PRO and FRV extractability also increased in both ozone-treated samples compared to the control (+ 8.6–9.1% for PRO and + 7.3–11.7% for FRV). No significant differences were found among treatments for individual anthocyanins in both cultivars at the end of maceration. Therefore, the use of ozone as sanitizing agent in red varieties prior to winemaking process can be considered because it did not negatively affect the extractability of skin anthocyanins and flavanols.

Starmerella bacillaris has been proposed as a non-Saccharomyces species candidate to be used in mixed fermentations with Saccharomyces cerevisiae for the production of wine. Among the prospective applications, reductions in ethanol content and the acetic acid produced from high sugar musts have attracted particular attention. In this study, we described the fermentation behavior of six strains of S. bacillaris in grape must with initial sugar concentration ranging from 200 to 330 g/L. Time (days of fermentation) was a second variable that was monitored for its influence on fermentation. Response surface methodology was employed to model the behavior of the strains. The six strains generally behaved uniformly. Residual sugar concentration and production of ethanol, glycerol, and acetic acid mainly depended on time. Initial sugar concentration in the must was positively associated with residual glucose in musts with higher initial sugar concentration. Similarly, malic acid consumption showed a dependence on time and sugar concentration and was inhibited in musts with a higher sugar content. The behavior of S. bacillaris strains can be considered compatible with enological practices that may involve mixed fermentation with S. cerevisiae.

This work aimed at investigating red wine olfactory&ndash, oral cross-modal interactions, and at testing their impact on the correlations between sensory and chemical variables. Seventy-four Italian red whole wines (WWs) from 10 varieties, and corresponding deodorized wines (DWs), were evaluated by sensory descriptive assessment. Total phenols, proanthocyanidins, ethanol, reducing sugars, pH, titratable and volatile acidity were determined. PCA results highlighted different sensory features of the 10 wine types. ANOVAs (p &lt, 0.05) showed that olfactory cues might play modulation effects on the perception of in-mouth sensations with 7 (harsh, unripe, dynamic, complex, surface smoothness, sweet, and bitter) out of 10 oral descriptors significantly affected by odours. Three weak but significant positive correlations (Pearson, p &lt, 0.0001) were statistically found and supported in a cognitive dimension: spicy and complex, dehydrated fruits and drying, vegetal and unripe. In the absence of volatiles, correlation coefficients between sensory and chemical parameters mostly increased. Proanthocyanidins correlated well with drying and dynamic astringency, showing highest coefficients (r &gt, 0.7) in absence of olfactory&ndash, oral interactions. Unripe astringency did not correlate with polyphenols supporting the idea that this sub-quality is a multisensory feeling greatly impacted by odorants. Results support the significance of cross-modal interactions during red wine tasting, confirming previous findings and adding new insights on astringency sub-qualities and their predictive parameters.

In winemaking, oenological tannins are used to preserve wine colour by enhancing the antioxidant activity, taking part in copigmentation, and forming polymeric pigments with anthocyanins. As a novel processing aid, in this study, a biosurfactant extract was evaluated as a solubilizing and stabilizing agent of anthocyanins in red wine. The biosurfactant extract under evaluation was obtained from a fermented residual stream of the corn milling industry named corn steep liquor (CSL). Two red winegrape varieties (Vitis vinifera L. cv. Aglianico and Cabernet sauvignon) were studied for anthocyanin content and profile, and colour traits, during simulated skin maceration for 7 days at 25 &deg, C, as well as polymerization and copigmentation at the end of maceration. A model wine solution was used as a control, which was added either with the CSL biosurfactant or with four different oenological tannins (from grape skin, grape seed, quebracho, and acacia). The results showed that CSL biosurfactant addition improved the colour properties of skin extracts by the formation of more stable compounds mainly through copigmentation interactions. These preliminary results highlighted that the effectiveness of CSL biosurfactant is variety-dependent, however, there is no significant protection of individual anthocyanin compounds as observed for delphinidin and petunidin forms using quebracho tannin.

The aim of this project was to register, in a liquid chromatography–mass spectrometry-based untargeted single-batch analysis, the metabolome of 11 single-cultivar, single-vintage Italian red wines (Aglianico, Cannonau, Corvina, Montepulciano, Nebbiolo, Nerello, Primitivo, Raboso, Sagrantino, Sangiovese, and Teroldego) from 12 regions across Italy, each one produced in their terroirs under ad hoc legal frameworks to guarantee their quality and origin. The data provided indications regarding the similarity between the cultivars and highlighted a rich list of putative biomarkers of origin wines (pBOWs) characterizing each individual cultivar–terroir combination, where Primitivo, Teroldego, and Nebbiolo had the maximum number of unique pBOWs. The pBOWs included anthocyanins (Teroldego), flavanols (Aglianico, Sangiovese, Nerello, and Nebbiolo), amino acids and N-containing metabolites (Primitivo), hydroxycinnamates (Cannonau), and flavonols (Sangiovese). The raw data generated in this study are publicly available and, therefore, accessible and reusable as a baseline data set for future investigations.

Plant proteins have been proposed as an alternative to animal-origin proteins in the wine industry because they are allergen-free and vegan-friendly. The aim of this study was to evaluate the effectiveness of plant proteins as fining agents on red wines with different phenolic composition. Two formulations for commercially available vegetal proteins (potato and pea origin) were assessed at two doses to modulate the fining treatment to the wine phenolic profile. The results evidenced that fining agents derived from plants have different levels of effectiveness on the removal of phenolic compounds depending on the origin, the formulation used, dose applied, and also wine characteristics. On Nebbiolo wine, the study was particularly significant due to its phenolic composition. One pea-based fining agent had an effect comparable to gelatin (animal origin) on the removal of polymeric flavanols with a minor loss of anthocyanins and therefore better preserving the wine color in terms of intensity and hue. For Primitivo, Montepulciano, and Syrah wines, even though there was a formulation-dependent effect, vegetal proteins gave more balanced reductions in terms of target phenolic compounds contributing to astringency and color perception., This research received partial funding from the University of Torino Local Research Initiative (Torino, Italy).

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.

The changes in the volatile composition of Moscato bianco grapes were evaluated during ripening. Grape berries were sampled for five weeks (16-20 °Brix) and sorted for each date in ten density classes (1.05-1.12g/cm(3)). The highest total concentration of free terpenes was found at 19.3 °Brix; however, total concentration of the bound fraction increased significantly throughout ripening. Response surface methodology was used to assess the simultaneous effect of sampling time and berry density on the volatile composition, which was satisfactorily fitted to regression models for some key terpene compounds. Total free and bound terpenes were more affected by grape density than by sampling date. The same behaviour was observed for free and bound linalool and bound nerol, whereas the stronger effect of sampling date was exhibited for bound t-rose oxide, c-rose oxide and geraniol. The results showed that the sampling strategy impacted strongly on the aroma quality of berries.

Sulfur dioxide (SO2) has antiseptic and antioxidant properties, and it is the most used preservative additive in winemaking and conservation. Possible allergenic effects of sulfites and consumer demand for “natural wines” have stimulated the interest of producers and researchers to rationalize the SO2 use. Most Saccharomyces yeasts produce modest amounts of sulfites, so the production of totally sulfite-free wines is a difficult task. The greatest efforts were devoted to limit compounds that permanently bind SO2, to increase its molecular form (pH management), and to research new preservative substances of natural origin. Technological advances offer great perspectives, particularly during wine stabilization, filling, and closing of bottles. The significant reduction of residual microbial charge and of the presence of oxygen in bottle makes it possible to greatly reduce the need for preservatives in the final product. Physical methods such as high pressure processing are also alternative proposals because of the capacity for microorganism inactivation.

Grape maturity at harvest strongly affects wine quality and, therefore, an adequate strategy of berry selection based on objective quality indicators is a key issue to produce high-quality and premium wines. In red wine technology, phenolic composition, aromatic profile, chromatic characteristics, mechanical properties, reducing sugars content, and acidity contribute most to grape quality. In the field, preharvest berry selection makes possible the identification of vineyard sections or even homogeneous groups of vineyards with similar grape composition. Precision viticulture approaches are highly profitable to manage harvest but require the use of advanced mapping technologies, involving drones, satellites, global positioning systems, geographic information systems, or local and remote sensors. However, intra- and intercluster variability in berry quality can be only solved in the winery. In this case, postharvest strategies are used such as manual sorting tables or automatic selection based on berry density and optical measurements (near-infrared/visible spectrometry) combined with multi- and hyperspectral imaging.

This study optimized clarifying Muscat blanc must with either Ca- or Na- bentonite and related mixes in a dose range of 10÷100 g/hL through a central composite design. Response surface methodology (RSM) estimated the combined effect of the bentonite type and dose on free (i.e., aglycons) and glycosylated aroma compounds. Heat stability, turbidity, and color were further analyzed. Results indicate that Na-prevalent bentonite mixes significantly reduced the must haziness, while mixes with 50% Ca-bentonite or higher led to negligible decreases. The surface plots from RSM predicted that aglycons of aroma compounds were removed by Na-bentonite at lower doses and by Ca-bentonite regardless of the dose. Further, the model estimated the removal of glycosylated aroma compounds, especially by Ca-prevalent bentonite at 50 g/hL. Despite the study’s experimental limitations, these outcomes will help the enological sector improve aromatic sparkling wine production.

International audience; Electrolyzed water (EW) has attracted much recent attention as a high-performance, new technology for its potential use in the food industry. However, the risk of postharvest EW treatments of winegrapes destined for winemaking is the chloroanisoles formation in the final product. In the present study, we investigated the impact of postharvest grape EW and storage treatments on the occurrence of these compounds in wine, 2,4,6-trichloroanisole (TCA) being the main compound responsible for the cork taint off-flavor due to its extremely low perception threshold. The results revealed that the presence of TCA in the wines depended on the concentration of residual free chlorine in the must from the EW treatment. Particularly, TCA was not detected in wine when active chlorine concentrations higher than 0.005 mg/L were present in the must. Chloroanisole and chlorophenol levels in wine were strongly affected not only by EW but also by grape storage conditions (temperature, time, sunlight exposition). The results showed that the 24-hours grape storage at a controlled temperature of 20 degrees C in the dark, after EW treatment, resulted in the highest TCA concentrations in wines (7.3 +/- 2.7 ng/L), while storage and withering in sunlight seemed to mitigate its presence in wine. This could suggest that microbiological formation of chloroanisoles may have been influenced by the storage temperature and germicidal effect of UV light. Biochemical mechanism of chloroanisoles production in grapes and wine is unknown, but the combination of residual free chlorine on the grape surface and the controlled storage conditions in the dark may have positively influenced the bio-formation of chloroanisoles and therefore their presence in wine.

Decreasing the ethanol content in wine is a current challenge, mainly due to the global climate change and to the consumer preference for wines from grapes with increased maturity. In this study, a central composite design (CCD) and response surface methodology (RSM) approach was used to investigate the potential application of Starmerella bacillaris (synonym Candida zemplinina) in combination with Saccharomyces cerevisiae, in mixed (co-inoculated and sequential) cultures, to understand better the mechanism of co-habitation and achieve the objective of reducing the ethanol in wines. Laboratory scale fermentations demonstrated a decrease up to 0.7 % (v/v) of ethanol and an increase of about 4.2 g/L of glycerol when S. cerevisiae was inoculated with a delay of 48 h with respect to the inoculation of S. bacillaris. Pilot-scale fermentations, carried out in winemaking conditions, confirmed the laboratory results. This study demonstrates that the combination of strains and inoculation protocol could help to reduce the ethanol content in wines.

The aim of this work was to compare different texture test conditions for the evaluation of instrumental mechanical and acoustic properties of raw and roasted hazelnut ( Corylus avellana L.) kernels cv. Tonda Gentile Trilobata (TGT). A comparison of compression and shear tests, test speed (0.2, 1.0, 10.0 mm/s), and analyzed axis (x, y, z) combinations was performed. Joint mechanical and acoustic emission acquisitions were used for the first time on hazelnut kernels. The compression test method using 1.0 mm/s speed and analyzed on the x-axis showed the lowest variability of the results. These conditions were then used to evaluate raw kernels during 12 months of storage, conducted in-shell (at ambient temperature) and shelled (refrigerated, vacuum, frozen, with nitrogen modified atmosphere). The main differences among storage conditions were evidenced in rupture force, rupture slope and acoustic maximum peak parameters.

The effects of continuous exposure to ozone gas (O3, 30 μL/L, 24 h) and immersion in electrolyzed water (EW, 400 mg/L free chlorine, 10 min) on skin hardness of Italia and Muscat Hamburg table grapes, and Merlot and Barbera wine grapes were investigated and compared with those of control treatments (air and deionized water). Skin hardness was instrumentally evaluated via measurements of skin break energy using a puncture test. For all cultivars and density classes, ozone treatment was more effective in increasing skin hardness than EW treatment, although the differences were not always significant. For the same treatment, skin hardening was independent of berry density, and the magnitude of this effect was cultivar-dependent. This skin hardening might positively affect the postharvest life of table grapes. In wine grapes, increases in skin break energy values were related to higher yields and slow extraction kinetics of phenolic compounds during maceration. Practical Applications The purpose and the originality of this work were to determine the real impact of continuous exposure to ozone gas and immersion in electrolyzed water on skin hardness in table grape and wine grape varieties. Differences in the treatment effect due to the grape maturity level were studied in berries sorted according to density. For all cultivars and density classes evaluated, ozone treatment was more effective for increasing skin hardness than electrolyzed water treatment although the differences were not always significant. Therefore, the use of ozone gas as alternative sanitizing agent could extend the postharvest life of table grapes and facilitate the extraction of phenolic compounds from wine grapes during maceration according to increased skin hardness.

Skins obtained from three different varieties (Georgia, San Giovanni and Tonda Gentile Trilobata) of roasted hazelnuts (Corylus avellana L.) were used at two different percentages (3% and 6%) in yogurt production to increase the dietary fibre and polyphenol content. The effects on the physico-chemical characteristics, antioxidant capacity, phenolic compounds, and sugar and organic acid content during 3 weeks of storage at 4 °C were evaluated, and a preference test was performed with consumers at the end of storage. The amount of skin and the variety used significantly influenced all of the physico-chemical parameters and were associated with consumer preference. Concerning the dietary fibre content, total polyphenol content and antioxidant capacity, all of which affect the functional ability of food products, the highest values obtained were for all of the products contained a hazelnut skin content of 6%. Among the cultivars, the highest values obtained were for yogurt with the Georgia hazelnut skin. Although 6% hazelnut skin yogurts displayed the highest functional ability, a decreased consumer preference was observed; yogurt with 3% San Giovanni and Tonda Gentile Trilobata hazelnut skins had the maximum consumer rating.

The impact of an enzyme preparation on the extraction of grape skin anthocyanins into a wine-like solution was evaluated during maceration (25 °C, 8 days). The study was performed on Vitis vinifera L. cv. Cabernet Sauvignon and Nebbiolo because of their different anthocyanin profiles, which are mainly composed of tri- and disubstituted forms, respectively. Maceration enzymes enhanced the skin releasing capacity for anthocyanins between 8% and 15% more, depending on the enzyme dose and variety, and shortened the time required to reach the maximum extraction yield by about 40 h, when compared to the control samples. The effect of enzymes on the profile and total content of anthocyanins during maceration was significant only for Cabernet Sauvignon. Therefore, a variety effect was found. In particular, the relative amount of malvidin glucosides increased up to 9% more whereas that of delphinidin, cyanidin and peonidin glucosides decreased up to 5%, 2% and 3% more, respectively, with the addition of the enzyme preparation. The results also showed lower anthocyanin degradation at maceration times longer than 72 h with the use of enzymes. Furthermore, the relationship between this enzyme effect and the instrumental skin hardness was assessed for the first time, as no previous study deals with the variation in the mechanical properties of the berry skin after using maceration enzymes. Significant positive relationships were found between the skin softening and the anthocyanin extraction yield (R > 0.69, p

Nowadays, the use of non-Saccharomyces yeasts in combination with Saccharomyces cerevisiae is a state-of-the-art strategy to improve complexity and enhance the analytical composition of the wines. This application has stimulated the interest of understanding how the non-Saccharomyces yeasts can contribute to the quality of the wines. The study presented here explores the potential use of Starmerella bacillaris (synonym Candida zemplinina) under winemaking conditions. Physiological and genetic characterizations of sixty-three isolates of Starm. bacillaris, previously isolated from four different varieties of grapes, were carried out. Both analyses revealed a low level of diversity between the isolates of Starm. bacillaris, while the fermentation trials in laboratory scale demonstrated the good enological performance of this species. The strong fructophilic character of this species and its ability to produce low quantities of ethanol and acetic acid and high amounts of glycerol were confirmed. The results, presented here, demonstrated a potential application of this non-Saccharomyces species in mixed wine fermentations with S. cerevisiae.

The wine industry worldwide is undergoing a chronic surplus of production, estimated at more than 30 millions of hectoliters. This extra waste (unsold wines) have to be handled in order to not aggravate the wine environmental impacts. With the aim to reduce this surplus, the present research evaluates new grape uses: by blending them with other fruits in the formulation of a “100% fruit juice”. The idea is to move from a linear model, in which grapes are grown only for wine production, to a complex one, in which grapes are grown for other uses too, in order to obtain a better use of raw materials, as opposed to waste production. This research apply a particular form of Industrial Ecology, integrating raw materials among farms. In order to evaluate the idea, a life cycle assessment was carried out, to make a comparison of two scenarios (the linear and the complex). Results show reduced emissions of greenhouse gases and a reduced amount of unsold wine to be treated. The wider market scenario provides healthy products to consumers: fruit juices. Regarding this last point, it should be emphasized that this fruit juice concept is already on the market since two years. This approach to wine surplus has demonstrated that transferring part of the must to the fruit juice production lightens the environmental load of a company (increased sustainability), lightens the unsold wine problem (increased efficiency in the resources use), and expands market opportunity by providing healthy products to consumers (increased competitiveness).

Background and Aims The instrumental measurement of crunchiness in tablegrapes has been the subject of little research in spite of the great relevance of this sensory texture trait to consumer preference. Therefore, our aim was to evaluate the potential of several mechanical and acoustic properties to assess the perceived firmness and crunchiness of tablegrape cultivars. Methods and Results The ripening effect was minimised by densimetric sorting of the berries before testing. The textural quality of seven tablegrape cultivars was evaluated by sensory analysis. Furthermore, three mechanical tests (texture profile analysis, cutting and denture) were performed on the berry flesh or on whole berries, and the acoustic emission produced was recorded simultaneously. Correlation studies showed strong and significant relationships between sensory texture attributes and instrumental parameters, particularly for the denture test. Nevertheless, satisfactory predictive accuracy for the perceived crunchiness required multivariate linear regression involving both mechanical and acoustic properties resulting from the denture test performed on whole berries. In this case, residual predictive interquartile amplitude was higher than 2. Most of the reliable models developed for perceived firmness are fairly recommended not for quantitative purposes but for fast screening (1.6

Gaseous ozone has been recently proposed as sanitizing agent to control mycobiota on grapes. The aim of this work was to evaluate the impact of ozone treatment during winegrapes dehydration (10 and 20% weight loss) on the content of phenolic compounds after treatment and their extractability during simulated maceration. The results showed that the ozone effect depends on the profile and content of anthocyanins and flavanols. For varieties characterized by prevalence of di-substituted anthocyanins and high flavanol contents, no significant differences were observed in phenolic compounds contents, but lower anthocyanin extractability was found. Instead, for varieties rich in anthocyanins and with a tri-substituted prevalent profile, lower anthocyanin contents were found at 20% WL, but their extractability was significantly increased. Using multivariate analysis, the extractability was correlated with skin cell wall composition and mechanical properties. Proteins, non-cellulosic glucose and total phenols contributed mainly to explain phenolic compounds extractability in withered grapes.

Mixed fermentations with Starmerella bacillaris and Saccharomyces cerevisiae affect the chemical composition of wines, by modulating various metabolites of oenological interest. The current study was carried out to elucidate the effect of sequential inoculation of the above mentioned species on the production of white wines, especially on the chemical and aromatic characteristics of Chardonnay, Muscat, Riesling and Sauvignon blanc wines. Titratable acidity and glycerol content exhibited evident differences among the wines after fermentation. For volatile compounds, mixed fermentations led to a reduction of the total esters, including ethyl acetate, which is a compound responsible for wine deterioration. However, Sauvignon blanc wines fermented by mixed cultures contained significantly higher levels of esters and thiols, both associated with positive sensory attributes. These findings suggest that sequential inoculations possess great potential in affecting and modulating the chemical and aromatic profile of white wines, especially those produced from Sauvignon blanc grapes.