IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Protein extracts of the Andean pseudocereals quinoa and kiwicha as alternatives for the fining of wine phenolics.

Protein extracts of the Andean pseudocereals quinoa and kiwicha as alternatives for the fining of wine phenolics.

Abstract

INTRODUCTION: Lately, there has been an increasing interest in using plant-derived proteins for wine phenolic fining. Proteins extracted from cereals, potatoes, and legumes have been proposed as effective fining agents, but only those from pea and potatoes have been approved for their use in wine. This work aimed at determining the fining ability of the Andean pseudocereals quinoa (Chenopodium quinoa Willd.) and kiwicha (Amaranthus caudatus L.) protein extracts (QP and KP respectively), compared to commercial fining agents, on red wines.

METHODOLOGY: The trials compared the performance of QP and KP, two potato protein extracts and gelatin, at two different contact times (48 and 96 h), on Cabernet Sauvignon wine. The turbidity was measured with a Hanna HI 83749 turbidimeter and results were expressed as NTU. Total phenolics (1), precipitable tannins (2), catechins (3), polymeric pigments (4), and CIELab parameters were determined spectrophotometrically. Low molecular weight phenolics were analyzed by HPLC (5).

RESULTS: QP and KP were effective in reducing the turbidity of the studied wine in a similar way than commercial fining agents. Treatments with QP and KP reduced total phenolics and total tannins similarly than commercial fining agents. Most of the treatments did not affect the flavan-3-ol content of wines. Our results allow us to hypothesize that the fining agents used are more likely to bind high molecular weight tannins than to those of low molecular weight or monomers. In some cases, treatments with QP and KP slightly decreased the color intensity similarly to other vegetable proteins.

CONCLUSIONS:

The fining ability of quinoa and kiwicha protein extracts has been studied for the first time. Results showed that QP and KP could be used as effective fining agents for
red wines as alternatives to animal proteins such as gelatin. The use of QP and KP as fining agents has the advantage of being non-allergenic products.

REFERENCES:

1. Waterhouse AL. Determination of Total Phenolics. In: Current Protocols in Food Analytical Chemistry. Hoboken, NJ, USA: John Wiley & Sons, Inc.; 2003.
2. Mercurio MD, Dambergs RG, Herderich MJ, Smith PA. High Throughput Analysis of Red Wine and Grape PhenolicsAdaptation and Validation of Methyl Cellulose Precipitable Tannin Assay and Modified Somers Color Assay to a Rapid 96 Well Plate Format. Journal of Agricultural and Food Chemistry. 2007 Jun 1;55(12):4651–7.
3. de Beer D, Harbertson J, Kilmartin PA, V R, T B, Adams DO, et al. Phenolics: A comparison of diverse analytical methods. American Journal of Enology and Viticulture. 2004 Sep;55:389–400.
4. Harbertson JF, Picciotto EA, Adams DO. Measurement of Polymeric Pigments in Grape Berry Extract sand Wines Using a Protein Precipitation Assay Combined with Bisulfite Bleaching. American Journal of Enology and Viticulture [Internet]. 2003;54(4):301–6. Available from: https://www.ajevonline.org/content/54/4/301
5. Gómez-Alonso, Sergio, Esteban García-Romero, and Isidro Hermosín-Gutiérrez. “HPLC analysis of diverse grape and wine phenolics using direct injection and multidetection by DAD and fluorescence.” Journal of Food Composition and Analysis. 2007; (20): 618-626.

DOI:

Publication date: June 24, 2022

Issue: IVAS 2022

Type: Poster

Authors

Pino Liudis1, Peña-Martínez Paula A.1 and Laurie V. Felipe1

1Facultad de Ciencias Agrarias, Universidad de Talca.

Contact the author

Keywords

Wine, plant protein, fining, tannin, phenolics

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

Assessing the climate change vulnerability of European winegrowing regions by combining exposure, sensitivity and adaptive capacity indicators

Winegrowing regions recognized as protected designations of origin (PDOs) are closely tied to well defined geographic locations with a specific set of pedoclimatic attributes and strictly regulated by legal specifications. However, climate change is increasingly threatening these regions by changing local conditions and altering winegrowing processes. The vulnerability to these changes is largely heterogenous across different winegrowing regions because it is determined by individual characteristics of each region, including the capacity to adapt to new climatic conditions and the sensitivity to climate change, which depend not only on natural, but also socioeconomic and legal factors. Accurate vulnerability assessments therefore need to combine information about adaptive capacity and climate change sensitivity with projected exposure to new climatic conditions. However, most existing studies focus on specific impacts neglecting important interactions between the different factors that determine climate change vulnerability. Here, we present the first comprehensive vulnerability assessment of European wine PDOs that spatially combines multiple indicators of adaptive capacity and climate change sensitivity with high-resolution climate projections. We found that the climate change vulnerability of PDO areas largely depends on the complex interactions between physical and socioeconomic factors. Homogenous topographic conditions and a narrow varietal spectrum increase climate change vulnerability, while the skills and education of farmers, together with a good economic situation, decrease their vulnerability. Assessments of climate change consequences therefore need to consider multiple variables as well as their interrelations to provide a comprehensive understanding of the expected impacts of climate change on European PDOs. Our results provide the first vulnerability assessment for European winegrowing regions at high spatiotemporal resolution that includes multiple factors related to climate exposure, sensitivity, and adaptive capacity on the level of single winegrowing regions. They will therefore help to identify hot spots of climate change vulnerability among European PDOs and efficiently direct adaptation strategies.

VINIoT – Precision viticulture service

The project VINIoT pursues the creation of a new technological vineyard monitoring service, which will allow companies in the wine sector in the SUDOE space to monitor plantations in real time and remotely at various levels of precision. The system is based on spectral images and an IoT architecture that allows assessing parameters of interest viticulture and the collection of data at a precise scale (level of grape, plant, plot or vineyard) will be designed. In France, three subjects were specifically developed: evaluation of maturity, of water stress, and detection of flavescence dorée. For the evaluation of maturity, it has been decided first to work at the berry scale in the laboratory, then at the bunch scale and finally in the vineyard. The acquisition of the spectral hyperstal image as well as the reference analyzes to measure the maturity, were carried out in the laboratory after harvesting the berries in a maturity monitoring context. This work focuses on a case study to predict sugar content of three different grape varieties: Syrah, Fer Servadou and Mauzac. A robust method called Roboost-PLSR, developed in the framework of this work (Courand et al., 2022), to improve prediction model performance was applied on spectra after the acquirement of hyperspectral images. Regarding the evaluation of water stress, to work with a significant variability in terms of water status, it has been worked first with potted plants under 2 different water regimes. The facilities have allowed the supervision of irrigation and micro-climatic conditions. The regression models on agronomic variables (stomatal conductance, water potential, …) are studied. To detect flavescence dorée, the experimental plan has consisted of work at leaf scale in the laboratory first, and then in the field. To detect the disease from hyper-spectral imaging, a combination of multivariate curve resolution-alternating least squares (MCR-ALS) and factorial discriminant analysis (FDA) was proposed. This strategy proved the potential towards the discrimination of healthy and infected leaves by flavescence dorée based on the use of hyperspectral images (Mas Garcia et al., 2021).

Mesoclimate impact on Tannat in the Atlantic terroir of Uruguay

The study of climate is relevant as an element conditioning the typicity of a product, its quality and sustainability over the years. The grapevine development and growth and the final grape and wine composition are closely related to temperature, while climate components vary at mesoscale according to topography and/or proximity to large bodies of water. The objective of this work is to assess the mesoclimate of the Atlantic region of Uruguay and to determine the effect of topography and the ocean on temperature and consequently on Tannat grapevine behavior.

Phenolic composition of Tempranillo Blanco grapes changes after foliar application of urea

Our research aimed to determine the effect and efficiency of foliar application of urea on the phenolic composition of Tempranillo Blanco grapes. The field experiment was carried out in 2019 and 2020 seasons and the plot was located in D.O.Ca Rioja (North of Spain). The vineyard was Vitis vinifera L. Tempranillo Blanco and grafted on Richter-110 rootstock. The treatments were control (C), whose plants were sprayed with water and three doses of urea: plants were sprayed with urea 3 kg N/ha (U3), 6 kg N/ha (U6) and 9 kg N/ha (U9). The applications were performed in two phenological stages, pre-veraison (Pre) and veraison (Ver). Also, each of the treatments was repeated one week later. Control and treatments were performed in triplicate and arranged in a randomised block design. Grapes were harvested at optimum ripening stage. High-performance liquid chromatography was used to analyse the phenolic composition of the grapes. Finally, the results obtained from the analytical determinations – flavonols, flavanols and non-flavonoid (hydroxybenzoic acids, hydroxycinnamic acids and stilbenes) – were studied statistically by analysis of variance. The results showed that, in 2019, U6-Pre and U9-Pre treatments increased the hydroxybenzoic acid content in grapes, and also all foliar treatments applied at Pre enhanced the stilbene concentration. Moreover, U3-Ver was the only treatment that rose flavonol and stilbene contents in the Tempranillo Blanco grapes. In 2020, all treatments applied at Pre enhanced the flavonol concentration in grapes. Furthermore, U3-Pre and U9-Pre treatments increased stilbene content in grapes. Nevertheless, the hydroxybenzoic acid content was improved by U6-Ver and U9-Ver and besides, hydroxycinnamic acid concentration in grapes was increased by all treatments applied at Ver. In conclusion, the lower and highest dose of urea (U3 and U9), applied at pre-veraison, were the best treatments to improve the Tempranillo Blanco grape phenolic composition.

Impact of climate variability and change on grape yield in Italy

Viticulture is entangled with weather and climate. Therefore, areas currently suitable for grape production can be challenged by climate change. Winegrowers in Italy already experiences the effect of climate change, especially in the form of warmer growing season, more frequent drought periods, and increased frequency of weather extremes.
The aim of this study is to investigate the impact of climate variability and change on grape yield in Italy to provide winegrowers the information needed to make their business more sustainable and resilient to climate change. We computed a specific range of bioclimatic indices, selected by the International Organisation of Vine and Wine (OIV), and correlated them to grape yield data. We have worked in collaboration with some wine consortiums in northern and central Italy, which provided grape yield data for our analysis.
Using climate variables from the E-OBS dataset we investigate how the bioclimatic indices changed in the past, and the impact of this change on grape productivity in the study areas. The climate impact on productivity is also investigated by using high-resolution convection-permitting models (CPMs – 2.2 horizontal resolution), with the purpose of estimating productivity in future emission scenarios. The CPMs are likely the best available option for this kind of impact studies since they allow a better representation of small-scale processes and features, explicitly resolve deep convection, and show an improved representation of extremes. In our study, we also compare CPMs with regional climate models (RCMs – 12 km horizontal resolution) to assess the added value of high-resolution models for impact studies. Further development of our study will lead to assessing the future suitability for vine cultivation and could lead to the construction of a statistical model for future projection of grape yield.