Enoforum 2021
IVES 9 IVES Conference Series 9 Enoforum Web 9 Enoforum Web Conference 2021 9 In-line sensing of grape juice press fractioning with UV-Vis spectroscopy

In-line sensing of grape juice press fractioning with UV-Vis spectroscopy

Abstract

UV-Visible spectroscopy in conjunction with chemometrics, was successfully applied to objectively differentiate sparkling wine press juice fractions of Pinot noir. Two measurements methods were applied: reflectance using a fibre optic probe in-line and transmission using a benchtop spectrophotometer. Different wavelength ranges for UV-Visible spectroscopy were evaluated and their ability to measure total phenolic concentrations in press juice fractions was compared. The differentiation of free run, early and late press fractions shows promise as a tool for the rapid discrimination of fractions when grapes for sparkling wine are pressed. Calibrations for total phenolics were prepared from press fraction spectral data using partial least square regression (PLSR) with a large number of wavelengths (230-700 nm) and multiple linear regression (MLR) using a small number of key wavelengths. Calibration performance for both reflectance and transmission spectra was similar, but the best performing calibration used reflectance spectra. Reflectance spectroscopy can thus be used in-line to predict total phenolics in grape juice with an acceptable accuracy and to discriminate press fractions. Insights from this research will lead to the design and building of a fitting that can be attached to any press outlet, with the potential to automate press fractioning.

DOI:

Publication date: April 23, 2021

Issue: Enoforum 2021

Type: Article

Authors

DAMBERGS Robert1*, LONGO Rocco2, KERSLAKE Fiona2

1 Charles Sturt University
2 Tasmanian Institute of Agriculture

Contact the author

Tags

Enoforum 2021 | IVES Conference Series

Citation

Related articles…

The smoking gun of climate change in wines

In this audio recording of the IVES science meeting 2022, Antonio Graca (Sogrape, Portugal) speaks about smoke taint and climate change. This presentation is based on an original article accessible for free on IVES Technical Reviews.

Influence of precipitation on the phenolic and isotopic composition of Vitis Vinifera red wines

This study investigates how precipitation from November to February during each harvest year, influence the phenolic and isotopic profiles of red wines, particularly focusing on trans-resveratrol, total phenolic compounds, and carbon and oxygen isotopes (¹³C/¹²C and ¹⁸O/¹⁶O).

Application of regenerative agriculture to viticulture: The REVINE project

Conventional viticulture improved the quality of production, but the economic costs can be unsustainable. Today, producers need to consider consumers’ demands for healthy, eco-friendly products. Institutions promote sustainable agriculture, with regenerative agriculture being the latest generation of methodologies focused on recovering losses and ensuring future sustainability. The revine project studies regenerative agricultural technology applied in mediterranean countries to provide precise indications for soil processing and effective vineyard treatments.

Effect of drought on grapevine wood fungal pathogen communities using a metatranscriptomics approach

Crops are facing increasing biotic and abiotic stress pressures due to global changes. However, trade-off mechanisms between these stresses and the underlying physiological processes are still poorly understood, especially in perennial crop species. To better understand these trade-offs, we studied the effect of drought on grapevine (Vitis vinifera) physiology and esca-related wood fungal communities. Esca is a vascular disease caused by a community of wood-infecting pathogenic fungi, and characterized by trunk necrosis, leaf scorch symptoms, yield losses, and mortality.

FERMENTATION POTENTIAL OF INDIGENOUS NON-SACCHAROMYCES YEASTS ISOLATED FROM MARAŠTINA GRAPES OF CROATIAN VINEYARDS

The interest in indigenous non-Saccharomyces yeast for use in wine production has increased in recent years because they contribute to the complex character of the wine. The aim of this work was to investigate the fermentation products of ten indigenous strains selected from a collection of native yeasts established at the Institute for Adriatic Crops and Karst Reclamation in 2021, previously isolated from Croatian Maraština grapes, belonging to Hypopichia pseudoburtonii, Metschnikowia pulcherrima, Metschnikowia sinensis, Metschnikowia chrysoperlae, Lachancea thermotolerans, Pichia kluyveri, Hanseniaspora uvarum, Hanseniaspora guillermondii, Hanseniaspora pseudoguillermondii, and Starmerella apicola species, and compare it with commercial non-Saccharomyces and Saccharomyces strains.