IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Measurement of synthetic solutions imitating alcoholic fermentation by dielectric spectroscopy

Measurement of synthetic solutions imitating alcoholic fermentation by dielectric spectroscopy

Abstract

Having the possibility to use a wide spectrum of elecromagnetic waves, dielectric spectroscopy is a technique commonly used for electrical characterization of dielectrics or that of materials with high energy storage capacity, just to name a few. Based on the electrical excitation of dipoles (polymer chains or molecules) or ions in relation to the characteristics of a weak external electric field, this method allows the measurement of the complex permittivity or impedance of polarizable materials, each component having a characteristic dipole moment.In recent years, the food industry has also benefited from the potential offered by this technique, whether for the evaluation of fruit quality or during the pasteurization of apple juice [1-3]. As the tests are fast and do not destroy the products, dielectric spectroscopy proved to be an experimental tool suitable for online measurements as well as long-term monitoring.The main objective of this study is to evaluate this technology’s potential to offer a new indicator of alcoholic fermentation during wine production. Synthetic solutions with only one component (fructose, glucose and alcohol) and several components imitating alcoholic fermentation were measured. Initially, two temperatures (18°C and 28°C) were used for simple solutions measurement and the results showed a significant impact of the temperature. At 18°C, simple solutions of fructose and alcohol at different concentrations were well distinguished but not at 28°C. Furthermore, the results were found to be dependent on the electrode measuring system (2 or 4 electrodes exhibit different results) but not on the type of electric excitation (sinusoidal excitation or a combination of two different excitation waves). While analyzing the data, strong correlations (>0,95) were found between the impedance values and the type of investigated solutions. This indicated the high potential of this technology as a new indicator for alcoholic fermentation control.   

References

1. Garcı́a, A., et al., Dielectric characteristics of grape juice and wine. Biosystems Engineering, 2004. 88(3): p. 343-349.
2. Fazayeli, A., et al., Dielectric spectroscopy as a potential technique for prediction of kiwifruit quality indices during storage. Information Processing in Agriculture, 2019.
3. Zhu, X., et al., Frequency- and temperature-dependent dielectric properties of fruit juices associated with pasteurization by dielectric heating. Journal of Food Engineering, 2012. 109(2): p. 258-266.

DOI:

Publication date: June 24, 2022

Issue: IVAS 2022

Type: Poster

Authors

Zeng Liming1, Preda Ioana2, Bapst Nicolas2, Pernet Arnaud1, Siebert Priscilla1, Cléroux Marilyn1 and Mertenat Muriel1

1Changins Viticulture and Enology College, University of Applied Sciences and Arts of Western Switzerland (HES-SO), Nyon, Switzerland
2iPrint Institute, University of Applied Sciences and Arts of Western Switzerland (HES-SO), Fribourg, Switzerland

Contact the author

Keywords

Alcoholic fermentation; capacitive sensor; frequency domain spectroscopy; dipolar and ionic polarization

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

Physiological and growth reaction of Shiraz/101-14 Mgt to row orientation and soil water status

Advanced knowledge on grapevine row orientation is required to improve establishment, management and outcomes of vineyards on terroirs with different environmental conditions (climate, soil, topography) and in view of a future change to more extreme climatic conditions. The purpose of this study was to determine the combined effect of row orientation, plant water status and ripeness level on the physiological and viticultural reaction of Shiraz/101-14 Mgt.

Effects of mechanical leafing and deficit irrigation on Cabernet Sauvignon grown in warm climate of California

San Joaquin Valley accounts for 40% of wine grape acreage and produces 70% of wine grape in California. Fruit quality is one of most important factors which impact the economical sustainability of farming wine grapes in this region. Due to the recent drought and expected labor cost increase, the wine industry is thrilled to understand how to improve fruit quality while maintaining the yield with less water and labor input. The present study aims to study the interactive effects of mechanical leafing and deficit irrigation on yield and berry compositions of Cabernet Sauvignon grown in warm climate of California.

The effects of cane girdling on berry texture properties and the concentration of some aroma compounds in three table grape cultivars

The marketability of the table grapes is highly influenced by the consumer demand; therefore the market value of the table grapes is mainly characterized by its berry size, colour, taste and texture. Girdling could cause accumulation of several components in plants above the ringing of the phloem including clusters and resulting improved maturity. The aim of the experiments was to examine the effect of girdling on berry texture characteristics and aroma concentration.

Application of a fluorescence-based method to evaluate the ripening process and quality of Pinot Blanc grape

The chemical composition of grape berries at harvest is one of the most important factors that should be considered to produce high quality wines. Among the different chemical classes which characterize the grape juice, the polyphenolic compound, such as flavonoids, contribute to the final taste and color of wines. Recently, an innovative non-destructive method, based on chlorophyll fluorescence, was developed to estimate the phenolic maturity of red grape varieties through the evaluation of anthocyanins accumulated in the berry skin. To date, only few data are available about the application of this method on white grape varieties.

Different yield regulation strategies in semi-minimal-pruned hedge (SMPH) and impact on bunch architecture

Yields in the novel viticulture training system Semi-Minimal-Pruned Hedge (SMPH) are generally higher compared to the traditional Vertical Shoot Positioning (VSP). Excessive yields have a negative impact on the vine and wine quality, which can result in substantial losses in yield in subsequent vintages (alternate bearing) or penalties in fruit quality. Therefore yield regulation is essential. The bunch architecture in SMPH differs from VSP. Generally there is a higher amount but smaller bunches with lower single berry weights in SMPH compared to VSP.