Combined effect of irrigation and compost application on Montepulciano berry composition in a volcanic environment of Latium region (central Italy)

Montepulciano red grape is cultivated in the northern part of the Latium region, primarily for the production of DOC “Colli Etruschi Viterbesi” structured wines for aging. In Mediterranean areas, viticulture is closely influenced by vine water status. In this context, the practice of irrigation may alleviate water-stress-related reductions in plant development to guarantee grape quality, especially in semi-arid areas. The application of on-farm compost in a vineyard may affect grape quality without negative effects, thereby enhancing environmental sustainability. The aim of this work was to investigate the combined effect of irrigation and compost application on the Montepulciano variety in the volcanic environment of Latium region, thereby improving the polyphenol concentrations in the berries. The trial was conducted during three growing seasons (2011–2013). Irrigation was performed according to the protocol proposed by Ojeda and Saurin (2014). The pre-dawn leaf water potential (ψpd) from July to September was measured weekly for maintaining vine water status in the range between -0.4 and -0.6 Mpa. Irrigation (I) and irrigation plus compost application (IC) were compared to a non-irrigated control (C). Berry weight was not influenced by moderate irrigation, whereas titratable acidity and total soluble solids were negatively correlated to the increment of water dropped. The primary finding was a positive influence on polyphenol contents of the grapes at harvest. Best performance was highlighted in 2012 with 263 liter vine-1 of water supplied. Overall, the sustainable use of water and on-farm compost improved Montepulciano grape quality in this volcanic area, thereby enhancing the adaptation of Mediterranean viticulture to climate change conditions

Oenological characterisation of indigenous strains of S. cerevisiae isolated in a biodynamic winery in the Cortona DOC area

Genotypic and technological characterisation of the S. cerevisiae population isolated in a biodynamic winery in the Cortona DOC area was performed to gain better knowledge of the variables that influence winemaking. The oenological performance of 11 S. cerevisiae strains was evaluated with physiological tests; strain typing was performed through analysis of interdelta sequences and 26S rDNA sequencing. The analysis revealed a remarkable variability in terms of S. cerevisiae strains, despite the homogeneity of wine features, underlining the high levels of biodiversity characterising biodynamic agriculture. Some strains were found in wines of different vintages, suggesting the presence of an established microbiota in the winery. Oenological tests demonstrated that while some yeasts provided reliable oenological performance, other strains were not able to accomplish prompt and effective alcoholic fermentation, or were characterised by spoilage characteristics, such as excessive production of volatile phenols or acetic acid. Indigenous strains of S. cerevisiae could be a useful instrument for reliable winemaking without altering the native microbiota of each oenological environment. However, characterisation of their oenological suitability, and the application of practices able to drive the evolution of microbiota, must be employed to reduce the risk of wine spoilage

“Wine yeast biodiversity during spontaneous fermentation in response to environmental stress”

“Natural wines”, nowadays, could appear an evocative recall to what wine was like before. During the ages, science allowed winemakers to produce wines with the full control of vinification condition, obtained mainly by addition of exogenous components, supplements and microorganisms. Contrarily, “natural wine” come back to basics and simplicity as invasive operations are avoided; but, on the other hand, a deeper knowledge and monitoring of winemaking process is required, in order to obtain high quality products without exogenous substances. Natural wine has been produced by spontaneous fermentation of must by yeasts originated from grapes and winery equipment. The wide variety of natural yeasts reflects the biodiversity, which is still under-exploited despite the large use of commercial Saccharomyces cerevisiae in most grape musts. During fermentation, several strains compete in the same fermenting must, and the dominance of Saccharomyces cerevisiae takes place when it overcomes all the others. The aim was to investigate Saccharomyces cerevisiae diversity and its technological behavior in two biodynamic wine farms in Tuscany. Autochthonous S. cerevisiae from Syrah fermentations were isolated and molecularly characterized in 2009 and 2013 harvests. Saccharomyces cerevisiae strains were isolated starting from Syrah musts with zero or low levels of sulphite added, according with the tendency of natural wines producers to abait every invasive operation during wine making. Samples were collected in different steps of winemaking. ITS-PCR method confirmed isolates belong to Saccharomyces sensu stricto complex. The multiplex PCR amplification of microsatellite loci (SC8132X, YOR267C and SCPTSY7) discriminated S. cerevisiae strains. Genetically diverse S. cerevisiae strains were subsequently subjected to technological characterization. Micro-fermentations were set up to study fitness and quality traits of biotypes characterized. Weight loss kinetics were measured and chemical analyses were performed. Collected Saccharomyces cerevisiae strains were tested also in order to verify the effect of low sulphite additions on biodiversity pursuing information about stress-adaptation mechanisms that allow the survival in the challenging environment of fermenting must. Sulphite addition may act as a selective factor to induce the presence and the activity of strains with diverse features about sulphite metabolism. The addition of different dose of sulphite induced a considerable variability among strains. However, some biotypes exhibited tolerance to certain concentration and only one biotype was classified as resistant to a determinate concentration. In addition, biotypes were subjected to an other environmental stress factor such as ethanol. The increasing of levels of ethanol limited considerably the activity of selected strains, but some of them highlighted a positive tolerance to various ethanol concentrations. During the harvest of 2013, the alcoholic fermentation was conducted inoculating a biotype characterized previously, which expressed good fermentative performance and a multi-strains culture of other S. cerevisiae strains characterized in the same harvest (2009) in a biodynamic farm from a workgroup of Edmund Mach Foundation of San Michele all'Adige (TN). The results of 2009 highlighted peculiar behaviors of 13 biotypes (characterized from four hundred isolates) that dominate the spontaneous fermentations. Not surprisingly, some biotypes were also found in fermentations of 2013, demonstrating yeasts are ubiquitous in that environment. Sensorial analyses of wine, originated by biotypes fermentation, revealed certain diversity in aroma and flavor traits, but also in the structure. Overall, this work suggests the consolidate relationship existing between autochthonous yeasts and the terroir, where yeasts are ubiquitous. Furthermore, autochthonous yeasts surely contribute to the unique identity of wine. In addition, this work suggests that the use of isolated and characterized autochthonous yeast strains could help the winemaking process, where the vintage could be inadequate to develop a particular product such as the wine of a specific wine farm

Biodiversita di lieviti in presenza di dosi crescenti di Anidride Solforosa nella fermentazione vinaria

Il presente lavoro fa parte di uno studio volto a verificare l’effetto dell’impiego di dosi modeste di anidride solforosa sulla biodiversità dei lieviti nella fermentazione spontanea. L’aggiunta di diossido di zolfo al mosto tende generalmente a ritardare l’inizio del processo fermentativo, riducendo il numero e il tipo di lieviti presenti, ma l’azione selettiva nei confronti di ceppi resistenti o tolleranti, caratterizzati da una migliore attività fermentativa, può portare ad un decorso fermentativo complessivamente più favorevole. Il presente lavoro, svolto in collaborazione con l’azienda Caiarossa, Riparbella (Pisa), ha incluso l’identificazione dei lieviti presenti durante la vinificazione di uve Syrah durante la vendemmia 2009, in relazione all’aggiunta di 0, 2 e 7 g/hL di anidride solforosa in forma di metabisolfito di potassio. Campioni di mosto sono stati sottoposti a diluizione seriale e inoculo su mezzi selettivi e non, allo scopo ottenere isolati microbici in coltura pura da sottoporre a successive analisi molecolari tra cui l’identificazione molecolare mediante amplificazione ITS e RFLP dell’amplificato ITS. Sono stati isolati e identificati lieviti appartenenti alle seguenti specie: Hanseniaspora uvarum, Pichia guilliermondii, Saccharomyces spp., Metschnikowia pulcherrima, Metschnikowia spp., Candida boidinii. I lieviti ritenuti appartenere al genere Saccharomyces, la cui presenza è stata rilevata già dai primi campionamenti, sono stati utilizzati per le successive prove di caratterizzazione mediante analisi di microsatelliti e RFLP di DNA mitocondriale. L’analisi dei profili di restrizione ha permesso di evidenziare la presenza di almeno sette diversi tipi di lievito appartenenti al genere Saccharomyces, che si sono alternati nei diversi trattamenti con dosi crescenti di anidride solforosa. In particolare alcuni degli isolati risultano particolarmente interessanti, in quanto rilevati a fine fermentazione nelle tesi in presenza di anidride solforosa e tra questi un’isolato risulta essere numericamente prevalente con contenuto di anidride solforosa maggiore. I ceppi isolati sono stati comparati con ceppi commerciali di ampia diffusione e non sono state rilevate similitudini

Improving winemaking in biodynamics oriented wine farming

Improving winemaking in biodynamics oriented wine farming Labagnara Tilde1., Toffanin Annita1. [email protected] 1.University of Pisa, DISAAA-a - Department of Agricultural, Food and Agro- Environmental Sciences, via del Borghetto, 80, 56124 Pisa “Natural wines”, nowadays, could appear an evocative recall to what wine was like before. During the ages, science allowed winemakers to produce wines with the full control of winemaking, obtained mainly by addition of exogenous components, supplements and microorganisms. Contrarily, “natural wines” come back to basics and simplicity as invasive operations are avoided; but, on the other hand, a very much deeper knowledge and monitoring of winemaking process is required, in order to obtain high quality products without exogenous supplies. “Natural wines” are produced by spontaneous fermentation of must conducted by yeasts originated from the grapes and winery equipment. During fermentation, several strains compete in the same must, and the dominance of Saccharomyces cerevisiae takes place when it overcomes all the others. The aim of the present work was to investigate Saccharomyces cerevisiae diversity and its behaviour in a biodynamic farm in Tuscany in order to supply knowledge to face vinification difficulties. Yeasts from Syrah fermentations were isolated from different steps of winemaking and molecularly characterized in 2009 and 2013 harvests. ITS-PCR methods identified those belonging to Saccharomyces sensu stricto complex and multiplex PCR amplification of microsatellite loci (SC8132X, YOR267C and SCPTSY7) discriminated S. cerevisiae strains. The results of 2009 highlighted peculiar behaviours of eight biotypes, characterised from two hundred isolates. Not surprisingly, some of the biotypes collected in 2009 were also found in 2013. In the last harvest one of the biotypes obtained in 2009 was used as inoculum in comparison with a multi-strain inoculum and with regular spontaneous fermentation. Sensorial analyses of wines obtained revealed certain diversity in aroma and flavour traits, but also in the wine structure

Biodiversity of wine yeast in response to environmental stress

Alcoholic fermentation is generally performed by Saccharomyces spp., especially by the principal wine yeast Saccharomyces cerevisiae. The wide variety of natural yeasts reflects the biodiversity, in most grape musts. During spontaneous fermentation, dynamics of microbial population results in successions of different strains, which contribute to the aromatic complexity and diversity of the wine. In the present work, Saccharomyces cerevisiae strains were isolated in 2009 during the harvest from biodynamic wine farms of Tuscany, starting from Syrah musts with zero or low levels of added sulphite, according to the tendency of “natural wines” producers to abate every invasive operation during wine making. By means of molecular techniques, thirteen different profiles of Saccharomyces cerevisiae strains were identified from a hundred isolates. The collected Saccharomyces cerevisiae strains were characterized, in order to verify the effect of low sulphite addition on biodiversity, pursuing information about stress-adaptation mechanisms that allow the survival in the challenging environment of fermenting must. Sulphite addition may act as a selective factor to induce the presence and the activity of strains with diverse features about sulphite metabolism. The different additions of sulphite induced a considerable variability among strains. Moreover, increasing levels of ethanol limited considerably the activity of the selected strains. Further gene-specific investigation may contribute to reveal the complex mechanism of resistance to environmental stress condition

Saccharomyces cerevisiae biodiversity in biodynamics oriented wine farming

In biodynamic oriented wine farming microbial biodiversity is favoured and it is reasonable to expect a major presence of microbes with interesting traits due to the absence o very scarce use of invasive techniques in the vineyard and in the cellar. The aim of the work was the identification and characterization of Saccharomyces cerevisiae wine strains from biodynamic oriented wine farms in different vintages. Yeasts from Syrah fermentations were isolated from different steps of winemaking in 2009, 2010 and 2013 harvests. S. cerevisiae biotypes were molecularly characterized using ITS-PCR and multiplex PCR amplification of microsatellite loci (SC8132X, YOR267C and SCPTSY7). Micro-fermentations of genetically diverse S. cerevisiae were set up to study fermentative traits. Sulphur dioxide, ethanol resistance and production of hydrogen sulphide were chosen as main parameters for technological characterization of isolates. During the harvest of 2009 and 2010, several S. cerevisiae biotypes were individuated during spontaneous fermentation in a biodynamic oriented wine farm located in Tuscany. Some biotypes highlighted good oenological aptitudes allowing their use in guided fermentation. The harvest of 2013 confirmed the presence of several biotypes previously identified in 2009 and 2010. There is a debate about the persistence of “autochthonous” wine yeast strains in the cellar and during winemaking process in the years. The results indicate the presence of the same S. cerevisiae strain in the examed 3 of 5 vinification processes, attesting its presence in the same terroir in different years and overcoming a possible vintage effect

EFFETTO DEL TRATTAMENTO FISICO SUL MICROBIOTA VINARIO IN AZIENDA BIODINAMICA

La macerazione carbonica è pratica diffusa nella produzione di vini rossi. Richiede il mantenimento in anaerobiosi delle uve prima della pressatura per facilitare la produzione di molecole organoletticamente interessanti e la dissoluzione dei componenti delle bucce nella polpa degli acini. Il controllo dei microrganismi può essere difficoltoso in quanto l'ambiente anaerobico stimola lo sviluppo di specie indesiderate. Il presente lavoro descrive l'effetto del trattamento fisico delle uve sulla composizione del microbiota durante il processo di vinificazione. Tre protocolli di vinificazione, con diversi trattamenti pre-fermentativi delle uve, sono stati esaminati mediante analisi microbiologiche su piastra e tecniche llumina MiSeq System. Gli esperimenti sono stati effettuati in un'azienda biodinamica, escludendo pertanto l'interferenza di starters a base di lieviti commerciali, sulla dinamica del microbiota oggetto di studio. La macerazione carbonica ha modificato l'evoluzione del microbiota durante la vinificazione, con effetti sul profilo chimico e organolettico dei vini ottenuti. Il maggior grado di biodiversità è stato osservato nelle vinificazioni a grappolo intero, specialmente per quanto riguarda la popolazione procariota, con presenza di Bacteroidales, Clostridiales, Oscillospira e altri gruppi microbici poco usuali durante la vinificazione, oltre a batteri lattici (principalmente Oenococcus sp.). Le analisi chimiche e sensoriali dei vini hanno evidenziato l'effetto dei diversi microbiota sulla composizione dei vini, il profilo in acidi organici e la percezione dei descrittori organolettici legati alla varietà ampelografica (Sirah). L'approccio biodinamico e l'assenza di aggiunte di anidride solforosa sembrano preservare la biodiversità microbica. Ulteriori esperimenti saranno necessari per chiarire le conseguenze della presenza di popolazioni di batteri considerati inusuali nel contesto ambientale vinario.Carbonic maceration is a practice used in the production of red wines. It requires anaerobic storage of grapes before crushing to allow the production of valuable molecules and the dissolving of skin components in berry pulp. There are difficulties in managing microbiota, because the anaerobic environment stimulates spoilage microorganisms. The work describes the impact of physical management of grapes on the composition of microbiota during the winemaking. 3 winemaking protocols, with different pre-fermentative management of grapes, were followed by plate count and Illumina MiSeq System approaches. The experiments were conducted in a biodynamic winery to exclude any interference due to microbial starters on grape microbiota dynamics. Carbonic maceration modified the evolution of microbiota during winemaking, with an impact on the chemical and organoleptic profile of wines. The highest biodiversity was observed in the experiment carried out with whole grapes, especially in the prokaryotic population, with the presence of Bacteroidales, Clostridiales, Oscillospira and other microbial groups not usually found during winemaking, as well as lactic bacteria (mainly Oenococcus sp.). Chemical and sensorial analysis of the wines highlighted the effects of different microbiota on the composition of wines, the organic acid profile and the perception of organoleptic descriptors linked to the vine cultivar (Syrah). The biodynamic approach and the absence of addition of sulphur dioxide, would seem to preserve microbial biodiversity. Further experiments should be performed to clarify the oenological consequences of the presence of bacterial populations not usually related to the oenological environment

Combined effect of irrigation and compost application on Montepulciano berry composition in a volcanic environment of Latium region (central Italy)

Montepulciano red grape is cultivated in the northern part of the Latium region, primarily for the production of DOC “Colli Etruschi Viterbesi” structured wines for aging. In Mediterranean areas, viticulture is closely influenced by vine water status. In this context, the practice of irrigation may alleviate water-stress-related reductions in plant development to guarantee grape quality, especially in semi-arid areas. The application of on-farm compost in a vineyard may affect grape quality without negative effects, thereby enhancing environmental sustainability. The aim of this work was to investigate the combined effect of irrigation and compost application on the Montepulciano variety in the volcanic environment of Latium region, thereby improving the polyphenol concentrations in the berries. The trial was conducted during three growing seasons (2011-2013). Irrigation was performed according to the protocol proposed by Ojeda and Saurin (2014). The pre-dawn leaf water potential (ψpd) from July to September was measured weekly for maintaining vine water status in the range between −0.4 and −0.6 Mpa. Irrigation (I) and irrigation plus compost application (IC) were compared to a non-irrigated control (C). Berry weight was not influenced by moderate irrigation, whereas titratable acidity and total soluble solids were negatively correlated to the increment of water dropped. The primary finding was a positive influence on polyphenol contents of the grapes at harvest. Best performance was highlighted in 2012 with 263 liter vine−1 of water supplied. Overall, the sustainable use of water and on-farm compost improved Montepulciano grape quality in this volcanic area, thereby enhancing the adaptation of Mediterranean viticulture to climate change conditions.Montepulciano cv. secrìa en el norte de la región Lazio de Italia para producìr vinos estructurados de la DOC “ColliEtruschiViterbesi”. En el contexto Mediterraneo la viticultura es estrechamente influenciada del estado hìdrico medioambiental. La pràctica de riego puede desminuìr el estrèshìdrico relacionado a la produciòn, y garantizar calidad de la uva. El uso del compost autoproducido puede favorecer la calidad de la uva mejorando la sostenibilidad. El objetivo de este trabajo fuèenvestigar el efecto del riego junto la aplicaciòn del compost, en la cv. Montepulciano en àreavolcànica de esa regiòn, para mejorar los polifenoles de las bayas. El proceso fuè conducido desde el 2011 hasta el 2013. El riego se realizò con arreglo al protocol de Ojeda y Saurin (2014). El potentialhìdrico de la hoja antes de amanecer (ψpd), desde Julio hasta Septiembre, fuè medido semanalmente para mantenerse en la gama – 0.4 y 0.6 Mpa. Las tesis experimentales regadas (I) y (IC), fueron comparadas con la tesi de Control (C). El peso de la baya no fuè influenciado con riego moderado; al contrario l'acidez y los sòlidossolubile han tenido una correlaciòn negativa con el incremento de agua. Es clara la influencia positiva para los polifenoles de la uva a la cosecha. La mejor actuaciònfuè del 2012 con 263 l/cepaje. En general el uso sostenible de agua y compost mejorò la calidad de la uva en este contexto volcanico, aumentando la adaptaciòn de la viticultura mediterranea a las condiciones del cambio climatico