terclim by ICS banner
IVES 9 IVES Conference Series 9 INVESTIGATION OF FILM COATINGS AS A PROTECTIVE LAYER IN REDUCING THE ABSORPTION OF SMOKE PHENOLS INTO PINOT NOIR GRAPES

INVESTIGATION OF FILM COATINGS AS A PROTECTIVE LAYER IN REDUCING THE ABSORPTION OF SMOKE PHENOLS INTO PINOT NOIR GRAPES

Abstract

Wine grapes exposed to wildfire smoke have resulted in wines with burnt and ashy sensory characteristics¹, that are undesirable qualities in wine. In extreme wildfire events, this can lead to total loss of grape crop. Currently there are no effective solutions in the market to prevent the uptake of smoke compounds into grapes. In this study, previously developed innovative film coatings were tested to analyze their effectiveness in reducing smoke phenol absorption². Four different cellulose nanofiber-based film types were investigated. The film types varied in their chitosan and/or β-cyclodextrin composition. Film coatings were applied at veraison in vineyards in the Rogue Valley and Willamette Valley. The Rogue Valley experienced two smoke events during the season from wildfires in California. The grapes from Willamette Valley experience heavy smoke exposure using designed smoke cages. At harvest, half of the grapes were washed to remove the films. This was to determine if smoke phenols were blocked or bound to the film coatings. Further analysis of the interaction of smoke phenols with film coatings was done by observing any volatile phenol diffusion through the film using a custom-made polytetrafluoroethylene apparatus. Free and bound smoke phenols in grape juice were analyzed using GCMS and smoke glycosides using LCMS³. Results show some of the film coatings were effective in reducing the amount of smoke compounds absorbed into the grapes, primarily guaiacol, 4-methyl guaiacol, syringol and 4-methyl syringol. The cresol compounds were not greatly impacted. The collective results of this study show promise for film coatings as an effective preventative technique for grape smoke exposure. Optimization of the film coating formulation will lead to the reduction in smoke sensory characteristics in wine and ultimately diminish the loss of product.

 

1. McKay, M., Bauer, F., Panzeri, V., Mokwena, L., & Buica, A.S. (2019). Potentially smoke tainted red wines: volatile phenols and aroma attributes. South African Journal of Enology and Viticulture, 40(2).
2. Tran, T.T., Jung, J., Garcia, L., Deshields, J.B., Cerrato, D.C., Penner, M.H., Tomasino, E., Levin, A.D., & Zhao, Y.(2023). Impact of functional spray coatings on smoke volatile phenol compounds and Pinot noir grape growth. Journal of Food Science, 88, 367– 380. 
3. Liu, Z., Ezernieks, V., Reddy, P., Elkins, A., Krill, C., Murphy, K., Rochfort, S., Spangenberg, G. (2020). A simple GC-MS/MS method for determination of smoke taint-related volatile phenols in grapes. Metabolites, 10(7), 294.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

L. Garcia¹, T. Tran¹, J. Jung², J.B. DeShields³, D.C. Cerrato², M.H. Penner⁴, A.D. Levin⁵, Y. Zhao⁶ and E. Tomasino⁴,*

1. Graduate research Assistant, Food Science & Technology, OSU, Corvallis, OR,
2. Assistant Professor Senior Research Associate, Food Science & Technology, OSU, Corvallis, OR,
3. Faculty Research Assistant, Department of Horticulture, Southern Oregon Research Center, OSU, Central Point, OR,
4. Associate Professor, Food Science & Technology, OSU, Corvallis, OR,
5. Associate Professor, Department of Horticulture, Southern Oregon Research and Extension, Central Point, OR,
6. Professor, Food Science & Technology, OSU, Corvallis, OR

Contact the author*

Keywords

smoke, remediation, film, phenol

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

VOLTAMETRIC PROFILING OF RED WINE COMPOSITION DURING MACERATION: A STUDY ON FOUR GRAPE VARIETIES

During red wine vinification, maceration allows the must, and consequently the wine, to be enriched with several compounds that contribute to the creation of the typical organoleptic characteristics of red wines. Among these, extraction of polyphenols (PPs) during maceration is a major process of enological interest.
The purpose of this study was the evaluate the suitability of a rapid analytical approach based in linear sweep voltammetry to monitor PPs extraction during vinification.

EFFECT OF FUMARIC ACID ON SPONTANEOUS FERMENTATION IN GRAPE MUST

Malolactic fermentation (MLF)¹, the decarboxylation of L-malic acid into L-lactic acid, is performed by lactic acid bacteria (LAB). MLF has a deacidifying effect that may compromise freshness or microbiological stability in wines² and can be inhibited by fumaric acid [E297] (FA). In wine, can be added at a maximum allowable dose of 0.6 g/L³. Its inhibition with FA is being studied as an alternative strategy to minimize added doses of SO₂⁴. In addition, wine yeasts are capable of metabolizing and storing small amounts of FA and during alcoholic fermentation (AF).

USING CHECK-ALL-THAT-APPLY (CATA) TO CATEGORIZE WINES: A DECISION-MAKING TOOL FOR WINE SELECTION

Bordeaux is the largest appellation vineyard in France. This contrasting vineyard with varied terroirs offers all styles of wine, resulting from the blending of several grape varieties. If these different profiles make the renown of Bordeaux wines, it can appear as a constraint when the aim is to study Bordeaux wines in their diversity. The selection of a representative sample can be performed by a sensory analysis carried out by trained panelists or by wine professionals, which can take several forms: consensus among experts, conventional descriptive analysis, typicality or quality evaluation. However, because of time, economic, and logistical constraints, these methods have limited applications. As an alternative to classical descriptive analysis, more intuitive methods that do not require training have been proposed recently to describe wines using an expert panel such as Napping, Free Choice or Flash Profiling, CATA or RATA.

EFFECT OF DIFFERENT VITICULTURAL AND ENOLOGICAL PRACTICES ON THE PHENOLIC COMPOSITION OF RED WINES

Global climate change is exerting a notable influence on viticulture sector and grape composition. The increase in temperature and the changes in rainfall pattern are causing a gap between phenolic and technological grape maturities [1]. As a result, the composition of grapes at harvest time and, consequently, that of wines are being affected, especially with regards to phenolic composition. Hence, wine quality is decreasing due to changes in the organoleptic properties, such as color and astringency, making necessary to implement new adaptive technologies in wineries to modulate these properties in order to improve wine quality.

ACIDIC AND DEMALIC SACCHAROMYCES CEREVISIAE STRAINS FOR MANAGING PROBLEMS OF ACIDITY DURING THE ALCOHOLIC FERMENTATION

In a recent study several genes controlling the acidification properties of the wine yeast Saccharomyces cerevisiae have been identified by a QTL approach [1]. Many of these genes showed allelic variations that affect the metabolism of malic acid and the pH homeostasis during the alcoholic fermentation. Such alleles have been used for driving genetic selection of new S. cerevisiae starters that may conversely acidify or deacidify the wine by producing or consuming large amount of malic acid [2]. This particular feature drastically modulates the final pH of wine with difference of 0.5 units between the two groups.