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…

PHOTOCHEMICAL DEGRADATION OF TRYPTOPHAN IN MODEL WINE: IMPACT OF HEAVY METALS AND OXYGEN ON 2-AMINOACETOPHENONE FORMATION

The wine industry worldwide faces more and more challenges due to climate change, such as increased dryness in some areas, water stress, sunburn and early harvesting during hot summer temperatures¹. One of the resulting problems for the wine quality might be a higher prevalence of the untypical aging off-flavor (ATA)². A substance, which Rapp and Versini made responsible for ATA, is the 2-aminoace-tophenone (2-AAP)³. 2-AAP in wine causes a naphthalene, wet towels, wet wool, acacia flower or just a soapy note⁴.

Read More

WINE FERMENTATION METABOLITES PRODUCED BY TWO TORULASPORA DELBRUECKII STRAINS ISOLATED FROM OKANAGAN VALLEY, BC, CANADA VINEYARDS

Wine aroma is influenced by various factors, from agricultural practices in the vineyard to the enological choices made by winemakers throughout the vinification process. Spontaneous fermentations have a characteristically deeper complexity of aromas when compared to fermentations that have been inoculated with Saccharomyces (S.) cerevisiae because of the diversity of microflora naturally present on grape skins. Non-Saccharomyces yeast are being extensively studied for their ability to positively contribute to wine aroma and flavour. These yeasts are known to liberate more bound volatile compounds present in grape must than S. cerevisiae through the enzymatic action of β-glucosidases and β-lyases1.

Read More

ANALYZING THE ROLE OF ELEMENTAL SULFUR IN GRAPE JUICE ON THE DEVELOPMENT OF POLYFUNCTIONAL MERCAPTANS IN SAUVIGNON BLANC WINES

Sauvignon blanc is characterized by distinctive aromas, both fruity and herbaceous. The “green” character has been attributed to the methoxypyrazines, while the “fruity” character is associated with polyfunctional mercaptans . Polyfunctional mercaptans are of great significance due to their high impact on wines and associated low perception thresholds.
Elemental sulfur (S⁰) is widely used to protect grapevines from powdery mildew.

Read More

SENSORY DEFINITION OF A TECHNICAL UNAVOIDABLE TRANSFER OF AROMA COMPOUNDS VIA SEALING IN A BOTTLING LINE IN ORDER TO PREVENT PROSECUTION DUE TO FRAUDULENT AROMATIZATION OF A SUBSEQUENTLY FILLED WINE

In 2020, 12% of all bottled German wines were aromatized, which may increase further due to rising popularity of dealcoholized wines. As sealing polymers of a bottling line absorb aroma compounds and may release them into regular wines in the next filling¹, this unintentional carry-over bears the risk to violate the legal ban of any aromatization of regular wine. However, following EU legislation, German food control authorities accept a technical unavoidable transfer of aroma compounds, if this is of no sensory significance.

Read More

METABOLIC INTERACTIONS OF SACCHAROMYCES CEREVISIAE COCULTURES: A WAY TO EXTEND THE AROMA DIVERSITY OF CHARDONNAY WINE

Yeast co-inoculations in winemaking have been investigated in various applications, but most often in the context of modulating the aromatic profiles of wines. Our study aimed to characterize S. cerevisiae interactions and their impact on wine by taking an integrative approach. Three cocultures and corresponding pure cultures of S. cerevisiae were characterized according to their fermentative capacities, the chemical composition and aromatic profile of the associated Chardonnay wines. The various strains studied within the cocultures showed different behaviors regarding their development.

Read More