terclim by ICS banner
IVES 9 IVES Conference Series 9 International Congress on Grapevine and Wine Sciences 9 2ICGWS-2023 9 Optimization of the acquisition of NIR spectrum in grape must and wine 

Optimization of the acquisition of NIR spectrum in grape must and wine 

Abstract

The characterization of chemical compounds related with quality of grape must and wine is relevant for the viticulture and enology fields. Analytical methods used for these analyses require expensive instrumentation as well as a long sample preparation processes and the use of chemical solvents. On the other hand, near-infrared (NIR) spectroscopy technique is a simple, fast and non-destructive method for the detection of chemical composition showing a fingerprint of the sample. It has been reported the potential of NIR spectroscopy to measure some enological parameters such as alcohol content, pH, organic acids, glycerol, reducing sugars and phenolic compounds.

This work focuses on the evaluation of the optimal parameters and pathlengths for fast measurement of the UV/VIS/NIR/MIR spectra in grape must and wine. The study was carried out with three different type of samples: (i) red wine cv Mencía, (ii) white wine cv Albariño, and (iii) grape must cv Albariño. Absorbance spectra were collected in rectangular quartz cuvettes of different optical pathlengths (1, 2, 5, and 10 mm) where different bandwidth parameters were tested.

The results indicated that increasing the optical pathlengths of the cuvettes increases the absorption intensity up to a saturation level (absorbance >2.5 units) at long wavelengths using long pathlengths (5 and 10 mm). The interpretation of the spectra also improves with 1 and 2 mm pathlengths. The bandwidth parameters evaluated indicated that using higher values, the spectrum appeared more defined, and the range of analysis was increased, reaching the MIR part of the spectrum.  In conclusion, the best combination of pathlength and bandwidth for the measurement of grape must and wine in the UV/VIS/NIR/MIR range is 1 mm of pathlength cuvette with the bandwidth set at 40 nm.

DOI:

Publication date: October 13, 2023

Issue: ICGWS 2023

Type: Poster

Authors

Manzano JI.1, Cozzolino D.2, Vilanova M.1

1 Instituto de Ciencias de la Vid y el Vino-ICVV (CSIC, UR, GR) 26007 Logroño (España)
2 Centre for Nutrition and Food Sciences (CNAFS), Queensland Alliance for Agriculture and Food Innovation (QAAFI), The University of Queensland, Brisbane, QLD 4072, (Australia)

Contact the author*

Keywords

NIR, wine, must, cuvette, bandwidth

Tags

2ICGWS | ICGWS | ICGWS 2023 | IVES Conference Series

Citation

Related articles…

A comprehensive study on the effect of foliar mineral treatments on grapevine microbiota, flavonoid gene expression, and berry composition

Recently, foliar treatments with mineral-based compounds have shown positive effects on grapevine production by protecting grape from thermal excesses and reducing the decoupling between technological and phenolic maturity caused by climate change. Unraveling the effect of mineral particle applications on grape-associated microbes is pivotal for successful wine processing, due to the influence of the microbiota on wine composition and stability. To our knowledge, this is the first work that comprehensively studied the effects of kaolin and chabasite-rich zeolitites treatments on grape-related microorganisms (by real-time PCR quantification of total fungi, Hanseniospora uvarum, Metschnikowia pulcherrima, plant-associated bacteria and lactic acid bacteria), the expression of genes related to the flavonoid biosynthesis (PAL1, CHS1, F3H2, DFR, LDOX, UFGT, MYBA1, GST4, FLS4 genes) and the berry composition (°Brix, pH, acidity and anthocyanin concentrations) in cv. Sangiovese during ripening in two growing seasons (2019 and 2020).

Agronomic behavior of three grape varieties in different planting density and irrigation treatments

In the O Ribeiro Denomination of Origin, there is a winemaking tradition of growing vines under a high-density plantation framework (8,920 vines/ha) and maintaining its vegetative cycle under rainfed conditions.
Currently, viticulture is advancing to plantation frames in which the density is considered medium (5,555 vines/ha), thus allowing mechanized work to be carried out for vineyard management operations. Although, the application of irrigation applied proportionally to the needs of the vegetative cycle of the vine, is a factor that increasingly helps a good development of the vine compared to the summer period, with increasingly uncertain weather forecasts.

The combined use of Lachancea thermotolerans and lactic bacteria in wine technology

The production of most red wines that are sold involves an alcoholic fermentation carried out by yeasts of the Saccharomyces genus, and a subsequent fermentation carried out by lactic bacteria of the Oenococus oeni species after the first one is fully completed. However, the traditional process can face complications, which can be more likely in grape juices with high levels of sugar and pH. Because of climate change, these situations are more frequent in the wine industry. The main hazards in those scenarios are halts or delays in the alcoholic fermentation or the growth of unwanted bacteria while the alcoholic fermentation is not done yet and the wine still has residual sugars.

Polyphenol content of cork granulates at different steps of the manufacturing process of microagglomerated stoppers treated with supercritical CO2 used for wine bottling

The wine closure industry is mainly divided into three categories: screw caps, synthetic closures, and cork-based closures. Among this latter, microagglomerated cork stoppers treated with supercritical CO2 are now widely used, especially to avoid cork taint contaminations[1]. They are designed with cork granules obtained from cork offcuts of the punching process during the natural cork stoppers production. A previous study[2] showed that these stoppers released fewer polyphenols in 12 % (v/v) hydroalcoholic solution than natural cork stoppers.

Towards the understanding of wine distillation in the production of brandy de Jerez. Chemical and sensory characterization of two distillation methods: continuous and batch distillation

Brandy de Jerez (BJ) is a spirit drink made exclusively from spirits and wine distillates and is characterized by the use of casks for aging that previously contained Sherries. The quality and sensory complexity of BJ depend on the raw materials and some factors: grape variety, conditions during processing the wine and its distillation, as well as the aging in the cask. Therefore, the original compounds of the grapes from which it comes are of great interest being in most cases the Airén variety. Their relationship with the quality of the musts and the wines obtained from them has been studied (1) and varies each year of harvest depending on the weather conditions (2).