Ultrasound application in winemaking

The aim of this work is study the effects produced by cavitation induced by ultrasound on different winemaking phases, in particular skin maceration, yeast lysis, color evolution and lees filterability. After some preliminary tests with laboratory equipment, an experimental design was created to optimize ultrasound conditions like time, amplitude and frequency depending on product treated and on enological objective. Tests that gave best results in the laboratory were compared to the traditional enological practices. Concerning skin extraction, best results were shown using 90% amplitude for 3-5 minutes with the frequency between 20 and 27 kHz, leading a significant increase in total phenolic compounds. Ultrasounds applied on crushed grapes before vinification reduced significantly maceration time on red grapes (up to 50%) and white grapes maceration for aroma extraction can be avoided. To evaluate the effect on yeast cell after fermentation, some trials were performed with ultrasounds on fine lees from white wines. The results showed a significant rise in yeast soluble cell compounds. This increment implies a reduction of aging period of wines on lees in comparison with conventional techniques. Recent experiences shows a significant effect of ultrasound treatment on juice and wine clarification lees that increase the tangential filtration performance in term of liquid recovery and treatment costs. Also the effect of ultrasounds on tannins and anthocyanins evolution were tested on young red wines, in order to investigate the changes during aging process. Good results were reached in each test and the use of ultrasound improve the tannin polymerization and color stability. An industrial plant was made for the winery application; the results obtained in pilot scale application in different viticulture region around the world, confirm good results for the different applications using few minutes of treatment. Technological factors (time and amplitude) must be calibrated depending on specific enological applicatio

Preliminary study of the effects of ultrasound on red wine polyphenols

The article evaluates the effect of high-power ultrasound (20 kHz) on the phenolic structure of red wines, to study the possible applications of this innovative technique in wine aging. Different treatment conditions, with times of 1, 3 and 5 minutes and amplitudes of 51, 102 and 153 \u3bcm, were applied. In the experimental conditions the main parameters related to the evolution of red wine phenolic compounds show interesting variations; in particular, we found significant differences on tannins evaluated with some indices of tannins reactivity. On the other hand, free anthocyanins do not undergo changes due to ultrasound application. The preliminary results, which definitely need a depth, nonetheless allow us to hypothesize the application of ultrasound technology to accelerate the aging of red wines, which normally requires (needs) long times in the cellar condition

INVESTIGATION ON VALBELLUNA AREA AND ITS OENOLOGICAL POTENTIALITY: CASE STUDY ON PROSECCO DOC

Context and purpose of the study - Valbelluna valley is an area located in the northeastern Italy. It is extended from the East-West between Feltre and Belluno, along the Piave waterway and enclosed between Cansiglio valley on the South and the Dolomites in the North. Here, the villages of Limana and Trichiana are present, which are considered for decades potentially interesting areas to aim a niche production with own particular properties.The position of this area, its sun exposition, its soil composition and the microclimate, are ideal factors to obtain vines and consequently wines with unique features especially regarding the diversity and complexity aroma. The viticulture is not new in Valbelluna valley, but nowadays the situation is deeply different. Up to the \u201860s the grape production was widely extended and it led 5,000/6,000 tons. The grape varieties produced were in particular hybrid such as Baco, Clinton and Isabella grapes. Viticulture and agriculture in Valbelluna suffered the countryside depopulation in particular after the Vajont disaster, that cancelled the majority of existent vines and in the postwar period, instead, there was an industrial increasing. The aim of this study is test and develop Glera vine in a different area it used to be, always an area presents in the Prosecco DOC area: Valbelluna. Material and methods - Some preliminary evaluations showed peculiar characteristics of Prosecco produced in this area such as marked acidity, coming from malic acid, savoury, well balanced, with a high expression and an important presence of floral aromas. Nowadays, this area is developing also the aromatic grapes production like Sauvignon, aromatic Traminer and Riesling. To have an objective evaluation about Valbelluna valley, place in which the Prosecco production is new, a study on sensorial features has carried out. It was led a comparison between Prosecco produced in Valbelluna and Prosecco coming from known DOC area in Veneto and Friuli Venezia Giulia.The sensory analysis was carried out to evaluate the Prosecco DOC position (from Valbelluna) respect the traditional one produced in DOC Veneto Friuli area and if some particular differences would have been between them. Results - The samples analyzed were statistically significant and they were tasted from a group of expert panel. The testing sections needed to define an organoleptic profile and compare the different samples. Data were analyzed with One-way Anova and Tuckey test.The results showed differences between Prosecco DOC from Valbelluna and traditional Prosecco DOC. In particular the Prosecco DOC sensory profile (from Valbelluna) differs from the other ones because of the floral wisteria taste, the olfactory intensity and pleasantness. The interesting results and differences in the organoleptic profile would allow next studies about the terroir potentiality in viticulture. Future investigations would have been regarding also viticultural aspects and, more in general, social aspects of Valbelluna area to define real potentiality in oenological production to promote a niche product as Prosecco DOC

In berry distribution and extraction of thiol precursors in Gew\ufcrztraminer.

The so-called varietal thiols are an interesting technological class of compounds that contributes to the "tropical" notes of wine. The factors governing the formation of their precursors and the conversion to the corresponding free forms are still discussed (Thibon et al. 2016) but, technologically speaking, the precursor availability is a prerequisite. Several data are present in the literature regarding Sauvignon Blanc (SB), while fewer deal with Gew\ufcrztraminer (GWT; Dubordieu and Tominaga 2009; Roland 2010a & b; Concejero et al., 2014), a variety native to Tramin, in South-Tyrol (Italy). For this reason, we investigated the concentration of 3-S-glutathionylhexan-1-ol (GSH-3MH) and 3-S-cysteinylhexan-1-ol (Cys-3MH) in GWT as regards: (1) the distribution between marks and juice in samples processed at a semi-industrial scale, in comparison with SB samples having similar \ub0Brix and pressing yield; (2) the effect of pre-fermentation skin-contact protocols, also used along with commercial enzymes to favour extractions from skin; (3) the fractioning during pressing on industrial-scale. Thiol precursors were analysed according to Larcher et al. (2013). GWT skins are characterised by a higher content in precursors compared to SB\u2019s at the same pressing yield, while this difference is turned upside down in juice. Pre-fermentation skin-contact significantly increased thiol precursors' concentration while the impact of the enzymes was not significant. Around 30% of total precursors are contained in the pressing fraction corresponding to the final 5% of the juice

Aromatic characterization of brazilian sparkling wines using olfactometry and a sensory panel

Brazilian sparkling wines, which currently account for 30% of the national production of fine wines, have been traditionally produced in the southern region since the 1910s. In Brazil, sparkling wine production increased 248% over the past 10 years, holding an 80% share of the domestic market wine. The objective of the present study was to establish sparkling wine typicality via aroma characterization by comparing quantitative and descriptive techniques for the main aromatic compounds. Sparkling wines from the major producing regions of Brazil were tested by two sensory panels, followed by gas chromatography analysis that allowed elucidation of their aromatic basis. Solid-phase microextraction was used for the extraction of the compounds, followed by detection using gas chromatography (GC), olfactometry and mass spectrometry (MS). Olfactometry and gas chromatography-mass spectrometry (GC-MS) identified 25 aromatic areas and 26 aromatic compounds, respectively. The majority of aromatic areas were associated with fruit descriptors, but floral aromas were also emphasized; these aromas often contribute to the elegance of sparkling wine and are highly valued by both consumers and experts. Fruity and floral aromas were highlighted by olfactometry. The ester found in the highest concentrations (GC-MS) was ethyl acetate, with a similar value to that found in aged Cavas. Sparkling wine 5 exhibited the highest mean value, which was almost double that of the lowest value in sparkling wine 6. Ethyl octanoate concentrations varied significantly, with sparkling wine 2 containing three times the amount found in sparkling wine 5. Ethyl butanoate values were similar for all sparkling wines. Isoamyl acetate was only found in sparkling wines 4 and 5. The mean concentration values of isoamyl, 1- propanol and isobutanol alcohols were lower than those studied sparkling wines from non-traditional cultivars. The mean values for hexanol were higher, which can be explained by the climatic conditions in southern Brazil. The aromatic description of sparkling wines, as established by the different evaluator groups. Fruity descriptors were predominant. Interestingly, there was a significant presence of roasted aroma descriptors, which are usually due to aging on lees and on oak, demonstrating that certain products develop for a long time. Furthermore, several evaluators described sweet aromas, which suggests good grape maturation and a quality winemaking process. Product complexity was also demonstrated by the description of floral and vegetative aromas. Most often, Brazilian and Italian sensory analysis panels cited pineapple and roasted or apple and fruit individual descriptors, respectively

Varietal thiol precursors in Gew\ufcrztraminer: effect of clone and grape ripening.

Much research has been carried out since the discovery of glutathionyl- (GSH-) and cysteinyl (Cys-) precursors of 3-mercaptohexan-1-ol (3MH) in grapes and juices (Tominaga et al.,1998; Peyrot des Gachons et al., 2002) in order to understand the origin of these precursors and optimize the technological options useful to liberate and maintain the free forms and the related fermentative compounds characterised by interesting tropical, passion fruit and grapefruit-like aroma. As few data are available about the role of these precursors in the case of Gew\ufcrztraminer (GWT; Roland Dubordieu and Tominaga 2009; Roland et al., 2010a & b; Concejero et al., 2014), an international variety native to Tramin (South-Tyrol, Italy) we investigated the effect of clone and ripening in grape samples of GWT grown in Trentino (Italy). The juices of 7 GWT clones - ISMA-AVIT 904, 906, 916, 918 and 920R, as well as LB14 and 1101 - grown in 4 plots and harvested at the technological ripeness allowed by the very hot 2015 vintage were analysed. Moreover, GWT grapes from 6 different non-clonal vineyards sited at a altitude between 120 and 525 m a.s.l. in Trentino were analysed during the last month before harvest. Thiol precursors were measured using an UHPLC approach with triple quadrupole mass detection according Larcher et al., (2013). Significant differences were found between clones as regards thiol precursors concentration in 2015 grape, the 906 and 920R clones showing a higher molar concentration of the sum of GSH-3MH and Cys-3MH compared to 916. A clear and statistically significant increasing trend during ripening was observed for the cited precursors, confirming for GWT previous results observed by Kobayashi et al (2010) for Koshu

La tecnologia ad ultrasuoni per il trattamento del pigiato di uve bianche

La tecnologia ad ultrasuoni, che trova diverse applicazioni nel settore alimentare e delle bevande, non \ue8 ancora stata introdotta nel settore enologico anche se sono parecchi gli studi di laboratorio relativi agli effetti su alcune fasi di processo della filiera vino. Solo a luglio 2019 la tecnologia ad Ultrasuoni \ue8 stata inserita dall\u2019OIV tra le pratiche ammesse nel trattamento dell\u2019uva pigiata e diraspata. Grazie all\u2019esperienza acquisita e agli interessanti risultati che riguardano la mecerazione delle uve rosse sono state realizzate numerose ricerche preliminari sul trattamento del pigiato di uve bianche, al fine di valutare l\u2019ipotesi di utilizzare gli ultrasuoni in questa delicata fase di lavorazione delle uve bianche aromatiche. Le esperienze di laboratorio e di cantina hanno consentito di verificare che il breve trattamento con ultrasuoni pu\uf2 sostituire integralmente la macerazione che si effettua per le uve bianche. Risulta interessante l\u2019effetto del tempo di trattamento sull\u2019estrazione dei componenti, tuttavia questa variabile dovr\ue0 essere gestita assieme all\u2019amplitudine nell\u2019impianto tecnologico al fine di poter garantire l\u2019estrazione dei componenti desiderati in funzione della maturit\ue0 dell\u2019uva e dell\u2019obiettivo enologico. Anche se non statisticamente significativi, gli incrementi in precursori e nella gradevolezza olfattiva evidenziano il positivo effetto del trattamento con ultrasuoni e confermano la possibilit\ue0 di sostituire integralmente la tradizionale macerazione effettuata nelle cantine sulle uve bianche aromatiche. In linea generale il trattamento con ultrasuoni consente di limitare i costi di produzione e di limitare anche eventuali trattamenti enzimatici estrattivi sul pigiato. Anche a livello energetico i consumi risultano molto limitati rispetto ad esempio a macerazioni a freddo spesso utilizzate in cantina per la macerazione delle uve bianche

Fertigation affects photosynthesis, modulation of secondary metabolism and sensory profiles of Vitis vinifera cv. “Schioppettino” withered grapes and wines

Nowadays a balance in plant production is required, especially in terms of nutrition, yield and for an optimal aroma and sensory profile of resulted wines. In this research, we compared two different methods of plant nutrition: one-single application (single-fertilization-SF) and two applications with the same amount adopting the fertigation (split fertigation-SpF), including a control not-treated, in a specific Italian region where grapevine Schiopettino cv. is being cultivated and this practice was not investigated yet. SpF promoted the photosynthesis parameters compared to a SF and to the non-treated vines (NTC). On these basis, the biological and physiological activity of the whole plant was enhanced. SpF treatment tendentially and significantly improved the qualitative, productive, physiological, and oenological parameters of “Schioppettino” wine

PRECURSORI DEI TIOLI VARIETALI DURANTE LA MATURAZIONE E LA PRESSATURA DELLE UVE DEL TRAMINER AROMATICO

Gli autori riportano l'evoluzione, in crescita in prossimit\ue0 della raccolta tecnologica indipendentemente dalle condizioni climatiche dell'annata, del glutationil- e del cisteinil-3-mercaptoesanolo, precursori dei tioli varietali. Ne riportano, inoltre, la concentrazione nelle diverse frazioni di pressatura. Tali precursori sono responsabili, previa fermentazione con adeguati ceppi di lievito, di note tropicali-agrumate che contribuiscono alla tipicit\ue0 del Traminer. Bench\ue9 il Traminer aromatico o Gew\ufcrztraminer (GWT) sia una variet\ue0 internazionale nota per l'elevata aromaticit\ue0 di origine terpenica riconducibile - a livello di uva - principalmente a geraniolo, citronellolo, nerolo e ossido di rosa, altre molecole varietali sono state riportate pi\uf9 recentemente fra quelle in grado di rivestire un ruolo tecnologico operativo. \uc8 il caso specificatamente dei cosiddetti tioli varietali e dei loro precursori, presenti questi ultimi nelle uve come risultante di diverse vie biosintetiche e/o tecnogeniche. Non \ue8 certamente questa la sede per una disanima di tali vie di formazione, vale per\uf2 la pena ricordare almeno che: \u2022 i principali, bench\ue9 non esclusivi, precursori sono il glutationil-3-mercaptoesanolo (GSH-3MH) e il cisteinil-3-mercaptoesanolo (Cys-3MH) (Dubordieu e Tominaga 2009; Roland et al. 2010 a, b; Concejero et al. 2014; Rom\ue1n Villegas et al. 2016; Nicolini et al. 2019) e che: \u2022 il manifestarsi delle interessanti note da frutta tropicale, frutto della passione e pompelmo passa attraverso la liberazione dei sopraccitati precursori dalla componente azotata e la successiva acetilazione fermentativa del 3-mercaptesanolo ad acetato di mercaptoesile, avendo come risultante, nei vini GWT, un apprezzato incremento della tipicit\ue0 (Rom\ue1n et al. 2018). In questa breve nota gli autori intendono presentare l'evoluzione dei precursori tiolici del 3-mercaptoesanolo durante la maturazione delle uve Traminer aromatico, cos\uec come osservata in Trentino Alto- Adige in due annate, il 2014 e il 2018, molto differenti dal punto di vista climatico e produttivo; il 2014 \ue8 stato infatti caratterizzato da temperature particolarmente fredde e significativa piovosit\ue0, mentre il 2018 da ben pi\uf9 favorevoli condizioni di clima e piovosit\ue0, associate per\uf2 a livelli di produzione decisamente elevati (Bottura 2015, 2019)

Study for the development of a rapid and non-destructive method for copper analysis in vineyards towards a precision fungal defense strategy

In the defense against downy mildew, copper is still widely used, particularly in organic management. At any rate, specific investigations are needed to significantly reduce the use of copper and minimize its environmental impact. This study, conducted in several farms in Friuli-Venezia Giulia (Northeast Italy), aimed to evaluate the concentration of copper on leaves in various climatic conditions, in order to create an important database for the development of a rapid control system through image analysis. The tests involved sampling leaves and grapes from bud break until the last treatment with copper-based products. After copper recovery using a nitric acid solution, the copper values were analyzed via ICP-AES analysis. Cuprotesmo imprints were also made on the same leaves to develop an application (APP) capable of quickly and non-destructively detecting copper on the leaf surface through image analysis. The analytical data revealed significant correlations between image analysis and copper values only in certain situations involving adult leaves. However, due to the variability in treatment situations, the use of the APP with image analysis for all copper defense scenarios is not yet feasible. Nevertheless, the results are encouraging and will serve for further extensive investigations to develop an image analysis system capable of detecting truly active copper and optimizing pesticide treatments for a precision defense strategy. This strategy aims to ensure low environmental impact, production sustainability, and grape quality