IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Use of a recombinant protein (Harpin αβ) as a tool to improve phenolic composition in wines

Use of a recombinant protein (Harpin αβ) as a tool to improve phenolic composition in wines

Abstract

Climate change is modifying environmental conditions in all wine-growing areas of the world. High temperatures are the cause of an increased imbalance between industrial maturity and phenolic maturity, resulting in berries with high sugar levels, low concentration in organic acids and reduced concentrations in aromas and phenolic compounds. These grapes produce wines with high alcohol content and lack freshness, color intensity, and aromatic complexity. Viticultural strategies have been developed in recent years in order to maintain the quality of red wines, with a two-fold objective: improve the phenolic composition of wines and reduce their alcoholic content. Harpin αβ is a recombinant protein and elicitor of hypersensitive responses. When Harpin αβ is applied to crops, the expression of growth and defense genes is stimulated. These genes are generally associated with metabolic signals and pathways related to functions of protein and sugar transport and vegetative development. The objective of this work has been to apply Harpin αβ to the vines after veraison in order to advance harvest for reducing the alcohol content of the final wines while maintaining or improving their phenolic composition compared to full maturity grapes. This experiment was carried out in a commercial vineyard sited in Jumilla (Spain). Three treatments were applied; i) Control: untreated application of Harpin harvested at 15º Baume, ii) 2T: grapes treated twice with Harpin, at the time of veraison and 15 days later and harvested at 13º Baume and iii) 3T: an extra application of the compound made 15 days after the second treatment and grapes were also harvested at 13º Baume. In each treatment, the dose of Harpin αβ applied was 150 g/ha. All treatments were vinified in the same way. Once the wines were bottled, the physicochemical and chromatic parameters were analyzed. Wines from grapes of 2T treatments harvested at 13º Baume decrease significantly the pH, color intensity and total phenolic index of the wines. No significant difference was observed in the total acidity parameter. On the other hand, 3T treatmen increased significantly total anthocyanins compare to control wines. Moreover, this treatment obtained the highest concentration of tannins, although these differences were not significant compared to the control treatment. It is clear that the 3T treatment was much more effective in improving the phenolic concentration of the wines than the 2T treatment. These results showed that the Harpin application in the vineyard (3T) produced wines with similar phenolic content that the wines produced from fully ripe grapes but with 20% less alcohol. This makes the use of Harpin αβ an interesting strategy for winemakers seeking a natural reduction of alcoholic content in their wines without losing quality.

DOI:

Publication date: June 24, 2022

Issue: IVAS 2022

Type: Poster

Authors

Martínez-Moreno Alejandro ¹, Martínez-Pérez Pilar ¹, Bautista-Ortin Ana Belén¹ Pérez-Porras Paula¹ and Gomez-Plaza Encarna ¹

¹Department of Food Science and Technology, Faculty of Veterinary Sciences, University of Murcia

Contact the author

Keywords

climate change, elicitors, grape ripening, alcohol

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.