TaqMan® and HRM approaches for SNP genotyping in genetic traceability of musts and wines

The fight against fraud in the wine sector requires continuous improvements and validations of new technologies applicable to musts and wines. Starting from published data from the Vitis18kSNP array, a series of new specific single nucleotide polymorphism (SNP) markers have been identified for some important north-western Italian cultivars, such as Barbera, Dolcetto and Arneis (Vitis vinifera L.), used in the production of high-quality wines under Protected Denomination of Origin. A pair of new SNP markers for each grape variety were selected and validated using two real-time PCR techniques: TaqMan® genotyping assays and high-resolution melting analysis (HRM). The TaqMan® assay has proven to be more reliable and repeatable than HRM analysis because despite being an economical and versatile technique for the detection of different types of genomic mutations (SNPs, insertions or deletions), HRM has shown limitations in the presence of poor-quality DNA extracted from musts and wines. TaqMan® assays have successfully identified Barbera, Dolcetto and Arneis in their respective musts and experimental wines, and with good efficiency in commercial wines. Marked differences between genotypes were observed, varietal identification in Dolcetto-based musts/wines was more efficient than that in Arneis-based wines. Therefore, the TaqMan® assay has considerable potential for varietal identification in wines and the procedure described in the present work can be easily adapted to all wines with adequate setup of DNA extraction methods that should be adapted to different wines.

Multivariate prediction of Saliva Precipitation Index for relating selected chemical parameters of red wines to the sensory perception of astringency

Astringency is an essential sensory attribute of red wine closely related to the saliva precipitation upon contact with the wine. In this study a data matrix of 52 physico-chemical parameters was used to predict the Saliva Precipitation Index (SPI) in 110 Italian mono-varietal red wines using partial least squares regression (PLSr) with variable selection by Variable Importance for Projection (VIP) and the significance of regression coefficients. The final PLSr model, evaluated using a test data set, had 3 components and yielded an R2test of 0.630 and an RMSEtest of 0.994, with 19 independent variables whose regression coefficients were all significant at p < 0.05. Variables selected in the final model according to the decreasing magnitude of their absolute regression coefficient include the following: Procyanidin B1, Epicatechin terminal unit, Total aldehydes, Protein content, Vanillin assay, 520 nm, Polysaccharide content, Epigallocatechin PHL, Tartaric acid, Volatile acidity, Titratable acidity, Catechin terminal unit, Proanthocyanidin assay, pH, Tannin-Fe/Anthocyanin, Buffer capacity, Epigallocatechin PHL gallate, Catechin + epicatechin PHL, and Tannin-Fe. These results can be used to better understand the physico-chemical relationship underlying astringency in red wine.

Volatile Compound Release from Oak Chips in Model Wine Media: Combined Influence of Toasting Degree, Size, Time of Contact, and Ethanol Content

The effects of size, toasting degree, and time of contact on the release of volatile compounds from Quercus alba (L.) chips during a simulated fermentation and post-fermentative process were studied. The results obtained indicated that the large-size chips favored the release of furfural and furfuryl alcohol, while the small ones increased the concentration of cyclotene and maltol. The interaction between chip size and time of contact showed that the small-size chips are more sensitive to the increase of ethanol concentration for the extraction rate of some compounds (furfural, vanillin, maltol, cyclotene, whiskey lactones, and eugenol) compared to the large-size ones, increasing their concentrations at the end of maceration. The toasting degree of oak chips had a different influence on the volatile compounds studied. Cyclotene and guaiacol concentrations increased with the toasting intensity, whereas the extracted concentration of all compounds increased from light to medium-toasted chips, except for eugenol, and then decreased by further increasing the toasting level for 5-methylfurfural, whiskey lactones, eugenol, and only using high-level toasted chips for furfuryl alcohol, maltol, and vanillin. A possible protection effect of the chip size toward the possible degradation or volatilization losses of furfural for high toasting degrees was observed.

Combined effect of harvest time and postharvest dehydration length on the composition of withered grapes for Sforzato di Valtellina DOCG wine production

BACKGROUND

Sforzato di Valtellina (Sfursat) is a PDO reinforced red wine produced in Valtellina (northern Italy) from partially withered red grapes (Vitis vinifera L.) cv. Nebbiolo. The present study aimed to evaluate the combined influence of different grape ripeness levels and withering length on the chemical composition, mechanical properties, and phenolic profile of Nebbiolo winegrapes from two Valtellina vineyards. During three consecutive vintages (2019, 2020, and 2021), three different technological binomials have been tested: early harvest/long withering (EL), medium-term harvest/medium-term withering (MM), and late harvest/short withering (LS).

RESULTS

At the end of the withering process, EL thesis usually presented the highest values of sugars and acidity. Extractable seed polyphenols showed a decreasing trend by leaving the grapes on the plant longer, and this effect increased considerably after withering with respect to fresh samples. EL and MM evidenced the greater concentration of these compounds expressed on grape weight, particularly for tannins. Instead, skin-extracted total phenolics were less influenced by the harvest time, whereas their concentration increased after withering. The harvest time appears to have a higher impact than the withering length on the final extractable anthocyanin content, although the trend was no stable during the vintages or common for the two vineyards evaluated. EL and MM experienced the highest contents of grape skin tannins in most cases, suggesting that a longer withering increases their concentration.

CONCLUSION

Harvest time and withering length can be modulated according to the desired oenological objective, promoting the valorization of grape potentialities. The choice to harvest the grapes earlier and enhance the withering length should be preferred to obtain wines with higher acidity and phenolic content, more suitable for long-ageing period. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Mouthfeel subqualities in wines: A current insight on sensory descriptors and physical-chemical markers

Astringency and more generally mouthfeel perception are relevant to the overall quality of the wine. However, their origin and description are still uncertain and are constantly updating. Additionally, the terminology related to mouthfeel properties is expansive and extremely diversified, characterized by common traditional terms as well as novel recently adopted descriptors. In this context, this review evaluated the mention frequency of astringent subqualities and other mouthfeel attributes in the scientific literature of the last decades (2000-August 17, 2022). One hundred and twenty-five scientific publications have been selected and classified based on wine typology, aim, and instrumental-sensorial methods adopted. Dry resulted as the most frequent astringent subquality (10% for red wines, 8.6% for white wines), while body-and related terms-is a common mouthfeel sensation for different wine types, although its concept is still vague. Alongside, promising analytical and instrumental techniques investigating and simulating the in-mouth properties are discussed in detail, such as rheology for the viscosity and tribology for the lubrication loss, as well as the different approaches for the quantitative and qualitative evaluation of the interaction between salivary proteins and astringency markers. A focus on the phenolic compounds involved in the tactile perception was conducted, with tannins being the compounds conventionally found responsible for astringency. Nevertheless, other non-tannic polyphenolic classes (i.e., flavonols, phenolic acids, anthocyanins, anthocyanin-derivative pigments) as well as chemical-physical factors and the wine matrix (i.e., polysaccharides, mannoproteins, ethanol, glycerol, and pH) can also contribute to the wine in-mouth sensory profile. An overview of mouthfeel perception, factors involved, and its vocabulary is useful for enologists and consumers.

Grape skin anthocyanin extraction from red varieties during simulated maceration: Influence of grape seeds and pigments adsorption on their surface

The impact of seeds on anthocyanin extraction from skins was assessed on four Italian red winegrape varieties presenting different anthocyanin profile. Grape skins were macerated alone or in presence of seeds for ten days in model solutions. Aglianico, Nebbiolo, Primitivo, and Sangiovese cultivars showed differences in the anthocyanin extraction rate, content, and profile. The presence of seeds did not significantly affect the anthocyanin content and forms extracted from skins and kept into solution, but it generally led to an increase in the polymerization rate. For the first time, anthocyanins adsorbed on seed surface have been quantified after maceration. The amount of anthocyanins retained by seeds was less than 4 mg/kg berries and it seems variety-dependent, with a possible role of seeds number and weight. Individual anthocyanin forms were adsorbed mainly according to their abundance in the solution, but cinnamoyl-glucoside anthocyanin forms showed a higher affinity with seed surface.

Assessment of Chestnut Gall Toughness: Implications for a Biocontrol Agent

(1) Torymus sinensis, the biocontrol agent of the Asian chestnut gall wasp Dryocosmus kuriphilus, is univoltine, but in NW Italy a small percentage of individuals exhibits a prolonged diapause, mainly as late instar larva. (2) In 2020, the diapause was investigated to evaluate its trend over the years. Due to the low survival rate of diapausing T. sinensis adults, the seasonal variation in the galls' toughness was evaluated, thus assuming that dry galls over time can negatively affect emergence. The window of vulnerability of the gall wasp galls was also evaluated in controlled conditions. (3) The results showed that the average number of second year T. sinensis emerging per 100 cells was 0.41 ± 0.05, and dead adults accounted for 4.1 ± 0.23 per 100 cells. Gall toughness resulted in lower values for galls collected in May and June, and then gradually increased over time. In general, no difference was detected in the wall toughness of galls formed during the previous year when compared to current-year dry galls. Oviposition was recorded on all the tested galls collected in May and June, and no difference in the number of oviposition events was detected. Conversely, no oviposition was observed in July. Comparing the number of oviposition events by T. sinensis and the gall toughness, a negative correlation was found (R² = -0.99). (4) The present findings contribute descriptive information on this gall's structural traits, and the influence on gall wasp management is also discussed.

Isomer composition of aroma compounds as a promising approach for wine characterization and differentiation: A review

The perceived aroma is the result of the presence of volatile organic compounds (VOCs) as well as the interaction among them and with the nonvolatile sample matrix. These compounds can derive from grape berries (varietal) and also be formed during winemaking and aging processes. Varietal VOCs are strongly influenced by the grape variety, ripening, and geographical origin. Therefore, they were proposed as markers for wine discrimination. Nevertheless, recent studies highlighted the higher discriminating ability of VOC isomer forms. In this review the potential and importance of VOC isomers for terpenes, C13-norisoprenoids, C6-alcohols, thiols, lactones, and fatty acid esters, as well as isomeric relationships for wine characterization and differentiation have been described to get a full view of possible applications for the wine industry, highlighting potentialities and limitations. VOC isomers can be of paramount relevance to find reliable markers for wine authenticity and fraud prevention, regarding variety and geographical origin. Each isomer form owns a different olfactory threshold, influencing strongly wine sensory characteristics. Certain oenological treatments during winemaking and aging were found to modify the isomeric profile, particularly yeasts, aging, and wood in contact with wine. Nevertheless, this research field has potential and new research advances are expected in this field.

P–095 Outcomes and predictive factors of successful salvage microdissection testicular sperm extraction (mTESE) after failed TESE in men with non-obstructive azoospermia: results from a multicenter study

Study question

We assessed the outcome and predictors of successful salvage microdissection testicular sperm extraction (mTESE) in non-obstructive azoospermia (NOA) men previously submitted to unfruitful classic (cTESE).

Summary answer

The sperm retrieval rate at salvage mTESE was almost 50%. Hypospermatogenesis and low FSH values were associated with positive outcomes at salvage mTESE

What is known already

In men with NOA testicular sperm can be retrieved using cTESE in approximately 50% of cases. mTESE has been proposed as a salvage treatment option for men with a previously failed TESE, but data are scarce.

Study design, size, duration

Multicenter, cross-sectional study. Complete data from 61 NOA men who underwent mTESE after a failed cTESE between 01/2014 and 10/2020, at 6 tertiary referral centers in Italy were analysed.

Participants/materials, setting, methods

All men underwent testicular ultrasound, hormonal and genetic blood testing. Histopathological diagnosis from TESE was collected in every man. Semen analyses were based on the 2010 WHO reference criteria. mTESE was performed according to the technique of Schlegel et al. (1999). Descriptive statistics and logistic regression models were used to investigate potential predictors of positive sperm retrieval (SR+) after salvage mTESE.

Main results and the role of chance

Overall, median (IQR) age and testicular volume were 35 (31–38) years and 10 (6–15) ml, respectively. Baseline serum FSH and total testosterone levels were 17.1 (8.6–30.4) mUI/mL and 4.7 (3.5–6.4) ng/mL, respectively. Sertoli-cell-only (SCO) syndrome, maturation arrest (MA) and hypospermatogenesis were found in 24 (39.3%), 21 (34.4%) and 16 (26.2%) men after cTESE, respectively. Spermatozoa were retrieved in 30 (49.2%) men at salvage mTESE. Patients with a diagnosis of hypospermatogenesis had a higher rate of SR + [12/16 (75%)] than those with MA [12/21 (57.1%)] and SCOS [6/24 (25%)] after salvage mTESE (p &lt; 0.01), which was bilateral in 36 (59%) cases. FSH was higher [16.5 (8–22) vs. 8.9 (5–13) mUI/mL, p &lt; 0.01] in SR- patients compared to SR+. No difference in clinical characteristics was found between patients with SR+ and SR- at salvage mTESE. There were no significant complications after mTESE. Multivariable logistic regression analysis showed that hypospermatogenesis (OR 9.7; p &lt; 0.01) and low FSH levels (OR 0.9, p &lt; 0.001) were independent predictors of SR+ after salvage mTESE, after accounting for age.

Limitations, reasons for caution

Despite we analysed one of the largest series of salvage mTESE, the samples size is too small to draw general conclusions. Because of the multicenter nature of the study we cannot rely on standardization of surgical techniques for TESE.

Wider implications of the findings: This is one of the larger studies on salvage mTESE. The selection of patients for salvage mTESE is of critical importance.

Trial registration number

na

Diversity of Italian red wines: A study by enological parameters, color, and phenolic indices

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.

Use of Untargeted Liquid Chromatography-Mass Spectrometry Metabolome To Discriminate Italian Monovarietal Red Wines, Produced in Their Different Terroirs

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.

Changes in Skin Flavanol Composition as a Response to Ozone-Induced Stress during Postharvest Dehydration of Red Wine Grapes with Different Phenolic Profiles

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.

Effect of flotation and vegetal fining agents on the aromatic characteristics of Malvasia del Lazio (Vitis vinifera L.) wine

BACKGROUND

Flotation is a process to reduce the must turbidity after grape pressing. The use of fining agents to reduce the polyphenol content is essential for white wine, but their impact on volatile compounds must be considered. Malvasia del Lazio juice (Vitis vinifera L.) was treated before flotation with animal gelatin (GEL), legume protein plus chitin (LEGCHIT), and legume protein plus yeast extract (LEGYEAST). The clarification efficiency, total polyphenols, and total proteins were determined in the grape must before and after flotation, as well as the volatile composition and sensory characteristics of the resulting wines.

RESULTS

The LEGCHIT trial was the most efficient, it being the fastest and achieving the lowest turbidity values. The GEL trial was the slowest, showing grape must turbidity values similar to LEGYEAST but also the highest total protein content. The vegetal protein treatments caused a decrease in the concentration of volatile organic compounds (VOCs) with respect to gelatin, which resulted in a reduction of aroma intensity, particularly for fruity and floral notes, but also for green notes. Furthermore, LEGCHIT wines were appreciated by panelists for their greater body and reduced astringency perception.

CONCLUSION

The use of legume protein combined with chitin as a fining agent for flotation is advantageous in terms of clarification efficiency for grape must. Furthermore, the wines obtained showed high perceived global quality, even though a higher loss (38% and 27% respectively for LEGYEAST and LEGCHIT) of VOCs occurred when compared with gelatin. © 2020 Society of Chemical Industry.

Chloroanisoles occurrence in wine from grapes subjected to electrolyzed water treatments in the vineyard

Recently the use of electrolyzed water (EW) attracted much attention as a high-performance, new technology for its potential use in the food industry. The aim of this work was to investigate the impact of grape EW treatments, applied at different time intervals prior to harvest, on the indigenous yeast populations of grape surface (Chenin blanc and Cabernet franc) and the occurrence of 2,4,6-trichloroanisole (TCA) in Cabernet franc wine. In addition, the evolution of inoculated and spontaneous fermentations on treated and non-treated grapes was also considered. The yeast population present on grape berries surface was influenced in a grape variety and EW treatment time-dependent way, since only Chenin blanc grapes treated with EW 7 days prior to harvest had significantly lower yeast population levels, compared to the respective control. Concerning the yeast diversity in the grape samples, a dominance of Aureobasidium pullulans was observed in treated grapes, independently of the grape variety. At the end of alcoholic fermentation, 2,4,6-trichloroanisole was detected in wine when the EW solution was applied at one or two weeks before harvest time. After wine storage, 2,4,6-trichloroanisole and chlorophenols contents generally exhibited a loss relative to initial values. The results showed that EW treatments tended to slightly increase the TCA concentration in final wine and did not affect the fermentation performances and chromatic properties of resulting wine. On the other hand, absorption or desorption phenomena by wine lees could be involved in the change of 2,4,6-trichloroanisole concentration in wine during storage time.

Influence of Different Dehydration Levels on Volatile Profiles, Phenolic Contents and Skin Hardness of Alkaline Pre-Treated Grapes cv Muscat of Alexandria (Vitis vinifera L.)

A dehydration experiment was carried out on Vitis vinifera L. cv 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 “Passolata”, “Bionda”, and “Malaga” 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.

Role of anthocyanin traits on the impact of oenological tannins addition in the first stage of red winegrape skin simulated maceration

In winemaking, exogenous tannins are added before maceration to improve future wine color characteristics derived from extracted grape anthocyanins. The study aimed to investigate the relation between different grape varieties, selected according to their anthocyanin profile, and the effect of five exogenous tannin formulations differing in origin and chemical features. Anthocyanin content, polymeric pigments, and color traits were assessed during a 72-hour skin simulated maceration. Grape skin-derived tannins increased color intensity (up to one unit) and polymeric pigments formation (up to 6.5%) in malvidin-prevalent Merlot and Cabernet sauvignon, with different extent depending on the anthocyanin richness. Grape seed-derived and ellagic formulations favored the pigment polymerization, the first in Nebbiolo and Sangiovese (up to 8.2%), which are characterized by high ratios of disubstituted anthocyanins, and the latter in malvidin-rich Syrah and Aglianico (up to 5%). A positive effect of quebracho regarded the defense of anthocyanin forms, particularly in Sangiovese and Nebbiolo.

Impact of Chemical and Alternative Fungicides Applied to Grapevine cv Nebbiolo on Microbial Ecology and Chemical-Physical Grape Characteristics at Harvest

Viticulture is a cropping system in which treatment against fungal diseases (in particular powdery and downy mildews) can be extremely frequent. Accordingly, a reduction in antimicrobial treatments and the application of environmentally-friendly compounds are becoming increasingly important for a more sustainable viticulture. In addition to their effect against pathogens, the impact of these products on the quality of the grapes is very important for the oenological industries, but unfortunately at present few data are available. We evaluated the effect of the application of biocontrol products and resistance inducers in the vineyard on the mechanical properties, microbial ecology, technological and phenolic maturity of Vitis vinifera "Nebbiolo" grapes at harvest. The yield and vigor of vines were not influenced by the treatments, nor were the production of primary and secondary metabolites. However, the active ingredients influenced the mechanical properties of the skin (hardness and thickness). A significant hardening of the skin was detected when laminarin and chito-oligosaccharides were used, and sulfur induced a thickening of the skin with potential consequences for wine quality. Furthermore, the yeast community present on grape berries was influenced by the treatments. The abundance of Aureobasidium pullulans, the dominant species on the grape berry, changed in response to the compounds used. In addition, Alternaria sp. was reduced in some treatments with a potentially positive effect on the quality and the safety of the grapes. This study provides an overview of the effect of biocontrol products and resistance inducers on microbial ecology and "Nebbiolo" grape quality, contributing to the establishment of more sustainable and effective defense strategies in viticulture.

Single-nucleotide polymorphism (SNP) genotyping assays for the varietal authentication of 'Nebbiolo' musts and wines

'Nebbiolo' (Vitis vinifera L.) is renowned for its use in producing monovarietal high-quality red wines, such Barolo and Barbaresco. The fight against fraud to safeguard high-quality productions requires an effective varietal identification system applicable in musts and wines. 'Nebbiolo'-specific single-nucleotide polymorphisms (SNPs) were identified starting from available databases and 260 genotypes analysed by Vitis18kSNP array. Two SNPs were sufficient to identify 'Nebbiolo' from 1157 genotypes. The SNP TaqMan® genotyping assays developed in this work successfully identified 'Nebbiolo' in all musts and wines collected at different experimental wine-making steps. The high sensitivity of the assays allowed identification of must mixtures at 1% and wine mixtures at 10-20% with non-'Nebbiolo' genotypes. In commercial wines, the amplification efficiency was limited by the low amount of grapevine DNA and the presence of PCR inhibitors. The TaqMan® genotyping assay is a rapid, highly sensitive and specific methodology with remarkable potential for varietal identification in wines.

Effect of mixed species alcoholic fermentation on growth and malolactic activity of lactic acid bacteria

In recent years, there is an increasing interest from the winemaking industry for the use of mixed fermentations with Starmerella bacillaris (synonym Candida zemplinina) and Saccharomyces cerevisiae, due to their ability to modulate metabolites of oenological interest. The current study was carried out to elucidate the effect of this fermentation protocol on the growth and malolactic activity of lactic acid bacteria (LAB) used for malolactic fermentation (MLF) and on the chemical and volatile profile of Nebbiolo wines and their chromatic characteristics. To this end, two LAB species, namely Lactobacillus plantarum and Oenococcus oeni, were inoculated at the beginning and at the end of the alcoholic fermentation (AF) performed by pure and mixed yeast using the abovementioned yeasts. The different yeast inoculation protocols and the combination of species tested influenced greatly the interactions and behavior of the inoculated yeasts and LAB during AF and MLF. For both LAB species, inoculation timing was critical to how rapidly MLF started and finished. Fermentation inoculated with L. plantarum, at the beginning of the AF, completed MLF faster than those inoculated with O. oeni. The presence of Starm. bacillaris in mixed fermentation promoted LAB growth and activity, in particular, O. oeni. Furthermore, LAB species choice had a greater impact on the volatile and chromatic profile of the wines than inoculation time. These findings reveal new knowledge about the importance of LAB species choice and inoculation time to ensure fast MLF completion and to improve wine characteristics in mixed fermentation with Starm. bacillaris and S. cerevisiae.

Coffee silverskin as nutraceutical ingredient in yogurt: its effect on functional properties and its bioaccessibility

BACKGROUND

Silverskin is a by-product obtained from coffee roasting. It is characterized by a high content of dietary fibre, phenolic compounds and caffeine. The aim of this study was to assess the silverskin obtained from two species of Coffea (Arabica and Robusta) at three percentages (2%, 4%, or 6%) into cow whole-milk yogurt to raise the nutraceutical value of the products and to verify the bioaccessibility of bioactive compounds during the shelf-life of 3 weeks.

RESULTS

The amount and origin of silverskin significantly influenced all the physicochemical parameters. Concerning the bioactive compounds, the highest levels were observed in yogurt supplemented with 6% of silverskin. Between the coffee species, Arabica yielded the highest 5-caffeoylquinic acid content and the strongest antioxidant activity, whereas Robusta gave the highest caffeine content. The digestion increased antioxidant activity in the yogurt, possibly because of greater accessibility of compounds.

CONCLUSION

The results obtained highlighted that silverskin can be used in yogurt production to increase the nutraceutical value of the products and that the bioactive compounds are bioaccessible during the digestion process. The characteristics and bioaccessibility of the resulting yogurt were strongly correlated with the coffee species and with the percentage added. © 2019 Society of Chemical Industry.

On-vine withering process of 'Moscato bianco' grapes: effect of cane-cut system on volatile composition

BACKGROUND

Cane-cut on-vine withering is a grape dehydration technique used for dry and sweet wine production. The aim of this work was to study the influence of the cane-cut technique applied at harvest to Moscato bianco grapes during the on-vine withering process to produce dehydrated berries with a different chemical composition and a volatile profile.

RESULTS

After 24 days of dehydration, an on-vine withering system using the cane-cut technique induced an increase in the total volatile content compared with grapes produced with a normal on-vine withering process. This increase was greater in glycosidically bound volatile compounds than in the free fraction. Bound linalool showed a significant increase of 52% when the cane-cut withering system was applied but the grapes that were normally withered appeared to be less prone to the loss of free linalool. A significant increase in the glycosylated forms of nerol and geraniol was also observed in the two on-vine withering systems on the 24th day compared with the control (fresh grapes at harvest date).

CONCLUSION

A cane-cut, on-vine withering system applied at harvest induced changes in the volatile composition of Moscato bianco grapes increasing total volatile content, consisting mainly of bound compounds, by the 24th day of dehydration. The grapes dehydrated on-vine using this new system also showed significantly greater content of most of the free volatile compounds detected. © 2018 Society of Chemical Industry.

Grape VOCs Response to Postharvest Short-Term Ozone Treatments

Ozone has been recently recognized as an efficient sanitizing agent in wine industry because of its powerful oxidizing properties. Furthermore, postharvest treatments of grapes with ozone can stimulate defense responses by synthetizing secondary metabolites against oxidative stress. In this study, the effect of postharvest short-term ozone treatments was assessed for the first time on free and glycosylated volatile organic compounds (VOCs) of winegrapes. Two different ozone concentrations (30 and 60 μL/L) and exposure times (24 and 48 h) were investigated just after treatment (fresh grapes) and after partial dehydration up to 20% weight loss (withered grapes). The study was carried out on Moscato bianco winegrapes (Vitis vinifera L.) due to the importance of terpenes in white aromatic cultivars to produce high quality wines. The results obtained showed that short-term ozone treatment caused a significant decrease in total contents of free VOCs in fresh grapes, mainly due to terpenes. Among them, linalool, geraniol, and nerol are the major aromatic markers of Moscato bianco grapes. Ozone entailed a significant decrease of free linalool contents in fresh grapes, the less stressful ozone treatment showing the smaller linalool degradation. However, the stronger and longer ozone treatment induced the synthesis of this compound probably in response to higher abiotic stress. Instead, significant changes were not observed in geraniol and nerol contents in fresh grapes. This last ozone treatment also reduced the loss of free linalool by water loss in withered grapes even though total VOCs and terpenes remained relatively stable. Furthermore, ozone seems to promote the synthesis of free (+)-4-carene and 4-terpineol in withered grapes under certain treatment conditions. Regarding glycosylated compounds, total VOCs and terpenes were less sensitive to ozone. Our findings highlight that ozone can be used as sanitizing agent in aromatic grape varieties prior to winemaking without affecting sharply the aromatic profile of fresh grapes and even improving it in withered grapes.

Treating varicocele in 2018: current knowledge and treatment options

PURPOSE

Varicocele is defined as a state of varicosity and tortuosity of the pampiniform plexus around the testis caused by retrograde blood flow through the internal spermatic vein. The prevalence of clinically relevant varicocele ranges from 5 to 20% in the male population and is often associated with infertility and reduction of sperm quality. In this review, the pathophysiology and clinical aspects of varicocele are reviewed along with therapeutic options and treatment effects on sperm parameters and fertility both in adult and in pediatric/adolescent subjects.

METHODS

We conducted a Medline and a PubMed search from 1965 to 2018 to identify publications related to varicocele clinical aspects, treatment procedures and treatment outcomes. Keywords used for the search were: "varicocele", "varicocelectomy", "sclerotherapy", "male infertility", "subfertility", and "semen abnormalities".

RESULTS

Data from a large number of studies in adolescent and adult males indicate that varicocele correction improves semen parameters in the majority of patients, reducing oxidative stress and improving sperm nuclear DNA integrity either with surgical or percutaneous approach.

CONCLUSIONS

Varicocele repair seems to represent a cost-effective therapeutic option for all males (both adolescent and adults) with a clinical varicocele in the presence of testicular hypotrophy, worsening sperm alterations or infertility. On the other hand, some investigators questioned the role of varicocelectomy in the era of assisted reproduction. Thus, a better understanding of the pathophysiology of varicocele-associated male subfertility is of paramount importance to elucidating the deleterious effects of varicocele on spermatogenesis and possibly formulating new treatment strategies.

Use of density sorting for the selection of aromatic grape berries with different volatile profile

The aim of the study was to investigate the application of berry density sorting as a tool for the selection of grapes with different volatile and precursor profiles. The study was carried out on Moscato giallo, Malvasia di Schierano, Malvasia nera lunga, and Brachetto aromatic grape varieties. Free and glycosidically-bound terpene compounds including linalool, geraniol, nerol, citronellol, and terpineol, as well as lipoxygenases activity-derived compounds, were evaluated using head space-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) in density sorted berries (1075-1119 kg m^-3). Total free terpenes changed with the berry density, while no significant changes were found in total glycosylated compounds, except for Malvasia nera lunga grapes where nerol, linalool, and geraniol contributed strongly to the increase of total contents with increasing berry density. Given that these variations were strongly variety-dependent, the possible use of density sorting equipment in winery for this aim may be less effective.

Winegrapes dehydration under ozone-enriched atmosphere: Influence on berry skin phenols release, cell wall composition and mechanical properties

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.

Impact of Increasing Levels of Oxygen Consumption on the Evolution of Color, Phenolic, and Volatile Compounds of Nebbiolo Wines

Since the end of the last century, many works have been carried out to verify the effect of controlled oxygen intake on the chemical and organoleptic characteristics of red wines. In spite of the large number of studies on this subject, oxygen remains a cutting-edge research topic in oenology. Oxygen consumption leads to complex and not univocal changes in wine composition, sometimes positive such as color stabilization, softening of mouthfeel, increase of aroma complexity. However, the variability of these effects, which depend both on the oxygenation conditions and the composition of the wine, require more efforts in this research field to effectively manage wine oxygen exposure. The present study is focused on the evolution of the chemical composition of four different Nebbiolo wines, each of them added with 4 different doses of oxygen (7, 14, 21, and 28 mg/L total intake) during the first month of storage. In this perspective, the evolution over time of wine color and polyphenols was studied. Acetaldehyde, glyceraldehyde and glyoxylic acid were quantified by HPLC. These compounds can play a role in wine aging creating condensed colored and stable products involving anthocyanins with or without tannins. Moreover, some volatile aldehydes correlated with oxidized olfactory notes, including methional and (E)-2-alkenals, have been quantified by GC-MS. Overall, during storage a decrease of color intensity, total and free anthocyanins and an increase in polymeric pigments (in particular the contribution to the red color of pigments not-bleachable by SO₂ or dTAT%) and some minor aldehydes was observed. Nevertheless, the differences in color parameters between the samples with different doses of oxygen were modest. These evidences were in contrast with an evident and detectable increase of free acetaldehyde content at increasing doses of oxygen measured after 60 days of storage. The effect of oxygen on color and production of SO₂ non-bleachable pigments during aging varies with wine composition, with Nebbiolo wines appearing not very reactive in this respect, probably due to their low content in anthocyanins and high content in tannins.

Volatile profiles and chromatic characteristics of red wines produced with Starmerella bacillaris and Saccharomyces cerevisiae

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.

Volatile profile of white wines fermented with sequential inoculation of Starmerella bacillaris and Saccharomyces cerevisiae

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.

Riparazione Trans-Vaginale di Fistola Neovescico-Vaginale

Introduction

Neobladder vaginal fistula is a known complication after cystectomy and orthotopic neobladder in women. The exact incidence is still unknown, even if in some of the largest series is reported in about 5% of female patients. We present our personal experience with a case of neobladder vaginal fistula.

Methods

A fifty-year old woman affected by T2G3 bladder cancer underwent radical cystectomy and orthotopic neobladder in December 2007. Definitive pathological examination revealed pT3aN0G3 urothelial cancer with squamous aspects. Two cycles of neoadjuvant chemotherapy were administered before cystectomy. Three weeks after cystectomy, a retrograde cystography revealed a fistula between vagina and neobladder. At first, the patient was treated conservatively, keeping the urethral catheter for two months. Cystographies, repeated every month, recorded a reduction in size of the fistula but not the complete closure. A surgical correction was planned. Preoperative cystoscopy showed the neobladder opening of the fistula on the posterior wall. Then a transvaginal approach with fistula excision and a two layer cross suture were performed.

Results

At the cystography performed 1 month after surgical repair no fistula was detected, and the patient was completely dry. At 3 months follow-up the patient was completely dry.

Conclusion

The development of a neobladder-vaginal fistula is a significant, even if infrequent, complication after cystectomy. In our case, we performed a transvaginal approach without tissue interposition, with good results. Such procedure is easy and effective and, in our opinion, can be tempted as first line surgical treatment.

Comparison of fortified, sfursat, and passito wines produced from fresh and dehydrated grapes of aromatic black cv. Moscato nero (Vitis vinifera L.)

Moscato nero d'Acqui is an Italian aromatic black winegrape variety characterized by a low content of anthocyanins (mostly tri-substituted), a satisfactory content of high molecular mass tannins, and a fair amount of terpenes. The grapes were subjected to a postharvest dehydration process under controlled thermohygrometric conditions (16-18°C, 55-70 RH%, 0.6m/s air speed) with the aim to produce three different special wine types (fortified, sfursat, and passito) from fresh, partially dehydrated (27°Brix), and withered (36°Brix) grapes, respectively. Chemical traits of produced grapes and wines were then evaluated through spectrophotometric, HPLC, and GC-MS methods. Increased contents of skin phenolic compounds and reduced extractable contents of seed phenolic compounds were observed as dehydration progressed. Few significant differences were found in the anthocyanin profile of grapes, although the relative abundance of coumaroylated anthocyanins was higher in dehydrated grapes. The predominant free volatile compound found in grapes was geraniol, which decreased with increasing water loss, whereas the contents of major glycosylated volatile compounds increased even above the concentration effect. The changes in the phenolic composition among wines agreed with those among grape skins. Fortified wines were chromatically unsatisfactory probably due to the low content of total anthocyanins, whereas sfursat and passito wines meet good chromatic characteristics as a result of the concentration effect during grape dehydration. Fortified and sfursat wines had free aroma profiles richer in 2-phenylethanol and citronellol, whereas passito wines were mainly composed of 2-phenylethanol and 2-phenylethyl acetate, citronellol being the predominant terpenol in all the wine types studied.

Impact of post-harvest ozone treatments on the skin phenolic extractability of red winegrapes cv Barbera and Nebbiolo (Vitis vinifera L.)

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 72h with gaseous ozone (30μL/L). Skin anthocyanin and flavanol extractability was assessed during maceration (6, 24, 48, 96, 168 and 240h) 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 24h ozone-treated berries, 72h 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.

'Fortified' wines volatile composition: Effect of different postharvest dehydration conditions of wine grapes cv. Malvasia moscata (Vitis vinifera L.)

The impact of postharvest dehydration on the volatile composition of Malvasia moscata grapes and fortified wines produced from them was assessed. The ripeness effect of fresh grapes on volatile compounds of dehydrated grapes was evaluated for the first time in this study. Fresh grape berries were densimetrically sorted, and more represented density classes were selected. Dehydration of riper berries (20.5 °Brix) led to volatile profiles richer in terpenes, particularly linalool and geraniol. The effect of dehydration rate on the volatile composition of dehydrated grapes and fortified wines was also evaluated. Fast dehydration grapes were richer in total free terpenes, and the resulting wines contained greater amounts of volatile compounds. The predominant compounds were free esters, but linalool, rose oxide, citronellol and geraniol can also contribute to wine aroma, particularly for fast dehydration. β-Damascenone can be an active odorant, although its contribution was greater in wines made from slow dehydrated grapes.