Guyot or pergola for dehydration of Rondinella grape

Abstract

AIM: Pergola veronese is the most important vine training system in Valpolicella area but Guyot in the last decades is diffusing. Rondinella is one of the three most important varieties to make Amarone wine. In this study we compared the response of Rondinella grape during postharvest dehydration from vines trained with Guyot or Pergola.

METHODS: Grapes were harvested at the same ripening stage but the grape production of Guyot and Pergola was quite different, higher in Pergola vines. Grape bunches were placed in commercial fruttaio and left to dehydrate with close-open system until reaching a weight loss of 30%. Samplings were done at 10, 20, and 30% weight loss. Berry juice enochemical analyses were performed with WineScanTM (Foss Italia) whereas the analyses of specific polyphenol compounds such as trans-resveratrol, quercetin-glucoside, and the monoglucoside anthocyanins were carried out by HPLC. Electronic nose was used to measure the juice headspace gas and GC/MS to analyze the specific VOCs (volatile organic compounds).

RESULTS: Not significant difference in the grape characteristics between the two samples were observed during dehydration; sugars increased at the same extent, about 30% in proportion with the weight loss. The acidity did not change and was similar between the two samples but malic acid initially decreased and then increased. FAN was much higher in Guyot sample at harvest and the difference was kept during dehydration, probably due to higher yield of Pergola. Guyot sample had a higher content in quercetin and monoglucoside anthocyanins while Pergola grapes had higher content in total polyphenols and total anthocyanins and specifically in trans-resveratrol and complexed anthocyanins. Electronic nose revealed a significant difference in grape must volatiles between the two samples which was validated by different concentration in VOCs. 

CONCLUSIONS

Guyot provide grapes with high content of free anthocyanins and quercetin while Pergola grapes have high content in trans-resveratrol and total anthocyanins that increased greater in Pergola than in Guyot. A significant difference in VOCs were measured which was validated by electronic nose

DOI:

Publication date: September 15, 2021

Issue: Macrowine 2021

Type: Article

Authors

Fabio Mencarelli

DAFE, UNIVERSITY OF PISA, ITALY,GREGORIO SANTINI, DAFE, UNIVERSITY OF PISA, ITALY  BRUNELLA CECCANTONI, SERENA FERRI, RAFFAELE CERRETA, ANDREA BELLINCONTRO, DIBAF, UNIVERSITY OF TUSCIA, VITERBO, ITALY  MARGHERITA MODESTI, LIFE SCIENCE INSTITUTE, SCUOLA S.ANNA, PISA  DANIELE ACCORDINI, CANTINA VALOPOLICELLA DI NEGRAR, NEGRAR (VR), ITALY

Contact the author

Keywords

grape dehydration, resveratrol, quercetin, training system

Citation

Related articles…

Testing the pathogen e-learning and field training course on grapevine virus knowledge and management

One of the reasons of the spread of grapevine virus diseases in
vineyards around the world is the lack of knowledge by the main actors of the wine sector. To face this problem, five partners worked together to develop the PAThOGEN project, a training program aimed to improve grapevine virus knowledge and management. The partnership gathers one French technical center (IFV), one Spanish university (USC), one Italian applied research center (CREA), one Spanish foundation
specialized in training and technology transfer (FEUGA) and one Italian SME specialized in the development of informatics tools and in knowledge transfer (HORTA).The objectives of PAThOGEN are: (i) to develop and
maintain a high-quality work-based Vocational and Education Training program, (ii) to improve the skills of professionals of the wine sector.

WINE LEES AS A SOURCE OF NITROGEN FOR OENOCOCCUS OENI TO IMPROVE MALOLACTIC FERMENTATION PERFORMANCE

Malolactic fermentation (MLF) is a desired process in red and acidic white wines, after alcoholic fermentation (AF), carried out by the lactic acid bacterium (LAB) Oenococcus oeni. The advantages are an increase of pH, microbiological stabilization and organoleptic improvement of the final wine. However, the presence of stress factors such as ethanol, low pH, high total SO2, lack of nutrients and presence of inhibitors, could affect the successful completion of MLF [1]. Changes in amino acid composition and deficiencies in peptides after AF, showed that MLF can be delayed, signaling its importance for bacterial growth and L-malic acid degradation during MLF [2].

HYDROXYTYROSOL PRODUCTION BY DIFFERENT YEAST STRAINS: SACCHAROMYCES AND NON-SACCHAROMYCES AND THE RELATION WITH THE NITROGEN CONSUMPTION

Hydroxytyrosol (HT) is a phenolic compound with extensive bioactive properties. It is present in olives, olive oil and wines. Its occurrence in wines is partly due to yeast synthetise tyrosol from tyrosine by the Ehrlich pathway, which is subsequently hydroxylated to .
The aim of the present work is to study how different yeast strains can influence in the HT production and, how the different nitrogen consumption of each strain can interfere the production of bioactive compounds.

Il Soave: esempio di cultura e di scienza

L’evoluzione del settore viti-enologico, supportato dalla ricerca ci propone sempre più frequentemente vini unici e inconfondibili. Il merito di ciò è da ricercare nel rapporto vitigno-territorio e dalla

Defining the terroir of the Columbia gorge wine region, Oregon and Washington, USA using geographic information systems (GIS)

The Columbia Gorge Wine Region (CGWR) extends for about 100km along the Columbia River and includes the Columbia Gorge American Viticultural Area (AVA) and the southwest portion of the Columbia Valley AVA.