terclim by ICS banner
IVES 9 IVES Conference Series 9 FREE TERPENE RESPONSE OF ‘MOSCATO BIANCO’ VARIETY TO GRAPE COLD STORAGE

FREE TERPENE RESPONSE OF ‘MOSCATO BIANCO’ VARIETY TO GRAPE COLD STORAGE

Abstract

Temperature control is crucial in wine production, starting from grape harvest to the bottled wine storage. Climate change and global warming affect the timing of grape ripening, and harvesting is often done during hot summer days, influencing berry integrity, secondary metabolites potential, enzyme and oxidation phenomena, and even fermentation kinetics. To curb this phenomenon, pre-fermentative cold storage can help preserve the grapes and possibly increase the concentration of key secondary metabolites.

In this study, the effect of grape pre-fermentative cold storage was assessed on the ‘Moscato bianco’ white grape cultivar, known for its varietal terpenes (65% of free terpenes represented by linalool and its derivatives) and widely used in Piedmont (Italy) to produce Asti DOCG wines. The study involved two experiments: a 12 h short-term storage under fresh (15 °C) and sunny outdoor (peak of 43 °C) conditions, and a medium-term storage under five different temperatures (5, 7, 12, 17, 19 °C) and durations (12, 24, 54, 84, 96 h), according to a Central Composite Design then evaluated using response-surface methodology (RSM). Berry skin break force mechanical property and juice physiochemical parameters were analyzed, as well as juice free terpene compounds using GC-MS.

In the short-term trial, after 4 and 8 h of storage the cooled sample showed a higher concentration of linalool, but at the end of the storage (12 h, when external temperature dropped to 25-20 °C after sunset), an opposite situation was found, possibly indicating a higher terpene solubilization in their thermotolerance defense role.

The medium-storage experiment indicated that the sum of the 13 detected terpenes in grape juice significantly decreased progressively after 75 h of storage, particularly in samples stored at the highest temperature tested (19 °C). However, the RSM model indicates that storage times shorter than 50 h contributed to higher terpenes, as well as the increase in storage temperature. The berry skin break force was not affected significantly by the treatments.

In conclusion, grape cold storage may offer several advantages in winemaking, but further studies are needed on this variety for assessing the best storage temperature and length conditions, as well as for the comparison between free and glycosidically-bound terpenes in juice and in the resulting wine. Acknowledgments. We thank Marco Rossetto and DENSO Thermal Systems (Poirino, Italy) for their support to this study.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Simone Giacosa¹, Stefania Savoi¹, Annachiara Lenti¹, Susana Río Segade¹, Maria Alessandra Paissoni¹, Andrea Bellincontro², Fabio Mencarelli³, Luca Rolle¹

1. University of Torino, Department of Agricultural, Forest and Food Sciences. Corso Enotria 2/C, 12051 Alba (CN), Italy
2. University of Tuscia, Department for Innovation in Biological, Agro-food and Forest systems. Via San Camillo de Lellis snc, Viterbo, Italy
3. University of Pisa, Department of Agriculture, Food and Environment. Via del Borghetto 80, Pisa, Italy

Contact the author*

Keywords

grape cold storage, aroma, terpenes, Muscat varieties

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

INFLUENCES OF SO2 ADDITION AND STORAGE CONDITIONS IN THE DETERMINATION OF MEAN DEGREE OF POLYMERIZATION OF PROANTHOCYANIDINS IN AGED RED WINES

The structural diversity is one of the most remarkable characteristics of proanthocyanidins (PA). Indeed, PA in wines may vary in the B-ring and C-ring substitutes, the C-ring stereochemistry, the degree of polymerization (DP) and the linkage between the monomers. Knowing in detail the structural characteristics of the PA of a wine can help us to understand and modulate several sensorial characteristics of the wine, such as color, antioxidant properties, flavor, and mouthfeel properties. In the last years was discovered and confirmed the presence of sulfonated monomeric and oligomeric flavan-3-ols in wine [1], as well as was pointed out their importance in wine quality [1,2].

HOW DO ROOTSTOCKS AFFECT CABERNET SAUVIGNON AROMATIC EXPRESSION?

Grape quality potential for wine production is strongly influenced by environmental parameters such as climate and agronomic factors such as rootstock. Several studies underline the effect of rootstock on vegetative growth of the scions [1] and on berry composition [2, 3] with an impact on wine quality. Rootstocks are promising agronomic tools for climate change adaptation and in most grape-growing regions the potential diversity of rootstocks is not fully used and only a few genotypes are planted. Little is known about the effect of rootstock genetic variability on the aromatic composition in wines; thus further investigations are needed.

Microbial ecosystems in wineries – molecular interactions between species and modelling of population dynamics

Microbial ecosystems are primary drivers of viticultural, oenological and other cellar-related processes
such as wastewater treatment. Metagenomic datasets have broadly mapped the vast microbial species
diversity of many of the relevant ecological niches within the broader wine environment, from vineyard
soils to plants and grapes to fermentation. The data highlight that species identities and diversity
significantly impact agronomic performance of vineyards as well as wine quality, but the complexity
of these systems and of microbial growth dynamics has defeated attempts to offer actionable
tools to guide or predict specific outcomes of ecosystem-based interventions.

PROTEOMIC STUDY OF THE USE OF MANNOPROTEINS BY OENOCOCCUS OENI TO IMPROVE MALOLACTIC FERMENTATION

Malolactic fermentation (MLF) is a desired process to decrease acidity in wine. This fermentation, carried out mostly by Oenococcus oeni, is sometimes challenging due to the wine stress factors affecting this lactic acid bacterium. Wine is a harsh environment for microbial survival due to the presence of ethanol and the low pH, and with limited nutrients that compromise O. oeni development. This may result in slow or stuck fermentations. After the alcoholic fermentation the nutrients that remain in the medium, mainly released by yeast, can be used in a beneficial way by O. oeni during MLF.

RED WINE AGING THROUGH 1H-NMR METABOLOMICS

Premium red wines are often aged in oak barrel. This widespread winemaking process is used, among others, to provide roundness and complexity to the wine. The study of wine evolution during barrel aging is crucial to better ensure control of wine quality.
¹H-NMR has already been proved to be an efficient tool to monitor winemaking process [1]. Indeed, it is a non-destructive technique, it requires a small amount of sample and a short time of analysis, yet it provides clues about several chemical families.