 IVES 9 IVES Conference Series 9 Mouthfeel effects due to oligosaccharides within a wine matrix

Mouthfeel effects due to oligosaccharides within a wine matrix

Abstract

The mouthfeel of wine is one of the most important aspects of the organoleptic experience of tasting wine. In wine a great deal is known about certain compositional components and how they impact mouthfeel perception, such as phenolics. But there are other components where little is understood, such as oligosaccharides. Saccharides in general are found in very low concentrations with wine, especially compared to conventional foods. There is very little information about how oligosaccharides influence the mouthfeel perception of wine. Given the large variance in types and concentrations of oligosaccharides present within the wine system this study aimed to understand their effects with as little variables as possible. This study utilized two different types of oligosaccharides at two different concentration levels to identify and quantify differences in mouthfeel perception within a model wine system. The two oligosaccharides in question, Fructooligosaccharide (FOS) and Glactooligosaccharide (GOS), were added to a basic wine model (14% ethanol, 4 g/L tartaric acid, pH 3.5) at a rate of 450ppm and 900ppm. Concentrations that have been measured in wine, resulting in four treatment groups, FOS450, FOS900, GOS450, GOS900, and one control group consisting of untreated model wine. All four treatment groups underwent triangle testing against the untreated control, and one additional triangle test between the low and high concentrations of the respective oligosaccharide. After triangle tests, all four treatments, and the untreated control underwent descriptive analysis via 100mm visual analog scales. Panelists for the descriptive analysis panel underwent training on sweetness, bitterness, viscosity, acidity, and astringency prior to the beginning of the panel. The results of the triangle tests showed a significant different between the FOS450 and FOS900 samples. However, interestingly neither the FOS450 nor FOS900 samples were found to be significantly different from the untreated control sample. Additionally, neither of the GOS samples were found to be significant from either each other or the control sample. Descriptive analysis found no significant difference in any of the five attributes tested. This indicates that the difference between the FOS450 and FOS900 samples may be above a detection threshold but may not be above a perception threshold. This would mean that a difference can be noticed, but not quantified. Future work will investigate differing levels of oligosaccharides and implement more training to better differentiate during descriptive analysis.

DOI:

Publication date: September 24, 2021

Issue: Macrowine 2021

Type: Article

Authors

Samuel Hoffman, Elizabeth Tomasino, Quynh Phan,

Graduate Research Assistant and MS Candidate, Oregon State University, Associate Professor, Oregon State University Graduate Research Assistant and PhD Candidate, Oregon State University

Contact the author

Keywords

mouthfeel, wine, oligosaccharides, descriptive analysis

Citation

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[1] Wohlfahrt Y., Tittmann S., Schmidt D., Rauhut D., Honermeier B., Stoll M. (2020) The effect of elevated CO2 on berry development and bunch structure of Vitis vinifera L. cvs. Riesling and Cabernet Sauvignon. Applied Science Basel 10: 2486

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