 IVES 9 IVES Conference Series 9 Microwave treatment of grapes: effect on the must and red wine polysaccharide composition

Microwave treatment of grapes: effect on the must and red wine polysaccharide composition

Abstract

AIM: The application of microwaves (MW) to the grape is a technique to reduce the contact time with pomace because it allows to break the cell walls of the berry. The objective of the study was to investigate the changes in the composition of polysaccharides in Cabernet-Sauvignon musts and wines made with grapes treated with microwaves.

METHODS: Red grapes were destemmed and crushed and divided into two batches. One batch was treated with MW at 700 Watts for 12 min and the other batch was not treated to be used as control. Three control microvinifications and three microvinifications treated with MW were carried out, all of them with three days of maceration. The content of each polysaccharide family in the samples was estimated as described by 1 and 2. MW improved the breakdown of cell walls of crushed grapes, thereby it significantly increased the content of polysaccharides rich in arabinose and galactose (PRAG), rhamnogalacturonans-II (RG-II), homogalacturonans (HL) and mannans/mannoproteins (MP) in musts. However, no significant differences were observed between the control and MW wines in the content of PRAG, RG-II, HL and MP.

CONCLUSIONS

MW allowed to increase the release of polysaccharides in must, although its effectiveness was not maintained in wines

DOI:

Publication date: September 7, 2021

Issue: Macrowine 2021

Type: Article

Authors

Belén Ayestarán

Institute of Grapevine and Wine Sciences (ICVV), Logroño, Spain,Leticia, MARTÍNEZ-LAPUENTE, Instituto de Ciencias de la Vid y el Vino (Universidad de La Rioja, Gobierno de La Rioja, CSIC), Finca de La Grajera, Ctra. Burgos 6, 26007 Logroño, Spain Mikel LANDIN, Instituto de Ciencias de la Vid y el Vino (Universidad de La Rioja, Gobierno de La Rioja, CSIC), Finca de La Grajera, Ctra. Burgos 6, 26007 Logroño, Spain Raquel, MUÑOZ GARCÍA, Facultad de Ciencias y Tecnologías Químicas (Universidad de Castilla-La Mancha), Avda. Camilo José Cela, s/n, 13071 Ciudad Real, Spain Zenaida, GUADALUPE, Instituto de Ciencias de la Vid y el Vino (Universidad de La Rioja, Gobierno de La Rioja, CSIC), Finca de La Grajera, Ctra. Burgos 6, 26007 Logroño, Spain

Contact the author

Keywords

microwave, polysaccharides, red must, red wine

Citation

Variety specific thresholds for plant-based indicators of vine nitrogen status

Aim: Several plant-based indicators of vine N status are reported in the literature. Among these, yeast assimilable nitrogen in grape must (YAN) and total N concentration of petiole and leaf blades are considered to be reliable indicators and so is the chlorophyll index, measured with a device called N-tester. The N-tester index is used to measure the intensity of the green colour of the leaf blade, and therefore to estimate its chlorophyll content.

Tasting soils in Pinot noir wines of the Willamette valley, Oregon

The conventional wisdom of vintners is that alkalinity, and thus less sour and more rounded taste, are enhanced in wine and grapes challenged by low-nutrient soils.

Qualitative and productive characterization of a minority variety: ‘Branco lexítimo’ in DO Ribeira Sacra (Spain)

The actual climate changes, together with the strong regulation of the European Union and Spanish government, in search of sustainable viticulture, have forced the recovery of minority varieties, expanding the range of grape varieties, as well as the possible development of wines with unique profiles. In the Ribeira Sacra DO (Spain), a comparative study of the agronomic and qualitative behavior of the ‘Branco lexítimo’ variety has been carried out, compared to the majority white variety in the DO: ‘Godello’, located in the same study plot, with identic soil and climatic conditions. The study contemplated the analysis of phenology and leaf water potential, as well as the productive results and the analysis of the must quality, during four seasons: 2018 – 2021.

The developement of vineyard zonation and demarcation in South Africa

L’histoire de viticulture de l’Afrique du Sud embrasse 340 ans, et a commencé, à la province du Cap, où les colonisateurs hollandais ont planté les premières vignes. L’arrivée des Huguenots français en 1688 a avancé, le développement.

ViniGWAS – improving the selection of climate-resilient grapevine varieties

Climate change and its consequences are becoming an increasing challenge for viticulture. The breeding of new grapevine varieties that are better adapted to the changing conditions offers a possible solution.