Macrowine 2021
IVES 9 IVES Conference Series 9 The influence of initial phenolic content on the outcome of pinot noir wine microoxygenation

The influence of initial phenolic content on the outcome of pinot noir wine microoxygenation

Abstract

Over the years, microoxygenation (MOX) has become a popular vinification technique to improve wine sensory qualities. However, among the impacting factors reported, only one published study (Cano-López et al. 2008) investigated the effects of initial phenolic content on wines undergoing MOX. The present study aims to establish the importance of this factor and specifically on light-coloured Pinot noir wines.Two Pinot noir wines with a low (PN1) and high (PN2) phenolic content were sterile filtered after malolactic fermentation and treated with two oxygen doses (i.e., 0.50 ± 0.08 and 2.17 ± 0.3 ppm/day) for 14 days with temperature control at 15oC. Control treatments had no MOX. Afterwards, the wines were aged for 1 month and followed by addition (100 mg/L) with the end point determined 4 days later.The results highlighted the importance of having high anthocyanin content for Pinot noir wines subjected to MOX on colour development. A higher anthocyanin content significantly increased colour intensity and resistant pigments in association with a greater increase in polymeric pigments. However, it did not guarantee colour stability, and bleaching erased the improvement on colour intensity in all wines.

We speculated that improvement of colour stability by MOX would be dependent on acetaldehyde production, forming pigments with the ethyl-bridged covalent bond that is more resistant to cleavage and bleaching. In this trials, limited acetaldehyde formation would expect after the removal of yeast with sterile filtration. Regarding tannin composition, MOX accelerated the decrease of (-)-epigallocatechin extension units in both PN1 and PN2. In PN1, the higher oxygen dosage led to the higher formation of tannin macromolecules and significantly lower tannin yield and (+)-catechin extension units, increasing the proportion of tannin terminals units.

These could be of concern for astringency perception (Ma et al. 2014). Therefore, MOX should be applied to Pinot noir and other low phenolic wines with caution.

DOI:

Publication date: September 13, 2021

Issue: Macrowine 2021

Type: Article

Authors

Yi Yang (Billy) 

The University of Auckland, New Zealand,Paul A. Kilmartin, The University of Auckland Rebecca C. Deed, The University of Auckland Leandro D. ARAUJO, Lincoln University

Contact the author

Keywords

microoxygenation, initial phenolic content, colour development, tannin composition, pinot noir wine

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.