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…

Bacterial community in different wine appellations – biotic and abiotic interaction in grape berry and its impact on Botrytis cinerea development

An in-depth knowledge on the conditions that trigger Botrytis disease and the microbial community associated with the susceptibility/resistance to it could led to the anticipation and response to the Botrytis emergence and severity. Therefore, the present study pretends to establish links between biotic and abiotic factors and the presence/abundance of B. cinerea.

Application of regenerative agriculture to viticulture: The REVINE project

Conventional viticulture improved the quality of production, but the economic costs can be unsustainable. Today, producers need to consider consumers’ demands for healthy, eco-friendly products. Institutions promote sustainable agriculture, with regenerative agriculture being the latest generation of methodologies focused on recovering losses and ensuring future sustainability. The revine project studies regenerative agricultural technology applied in mediterranean countries to provide precise indications for soil processing and effective vineyard treatments.

The effects of perennial cover crop management on soil temperature and vine water status

The implications of perennial cover crop management on vine vigor and yield have been well documented. However, whereas multiple studies show that cover crop management affects grapevine dry matter production, water, and nutrient status, the specific effects of a new hybrid perennial cover crop on soil temperature and its relationship to vine water status in vineyards has not been explored. This study will compare 3 different perennial cover crop combinations and tillage practices with a no-till seeding of a new hybrid perennial, Poa bulbosa (Pb).

Proteomic profiling of grape berry presenting early loss of mesocarp cell vitality

From fruit set to ripening, the grape berry mesocarp experiences a wide range of dynamic physical, physiological, and biochemical changes, such as mesocarp cell death (MCD) and hydraulic isolation. The premature occurrence of such events is a characteristic of the Niagara Rosada (NR) variety, utilised as table grapes and winemaking. In our opinion, the onset of ripening would not cause MCD, but a down-regulation of respiratory enzymes during the early loss of cell viability, while maintaining membrane integrity. For this, we investigated three distinct developmental stages (green (E-L33), veraison (E-L35), and ripe (E-L39)) of NR berries by label-free proteomics, enzymatic respiratory activity and outer mesocarp imaging. Cell wall-modifying proteins were found to accumulate differently throughout ripening, while cytoplasmic membranes continue intact.

Influence of temperature and light on vegetative growth and bud fruitfulness of grapevine cv. Semillon

Aim: To investigate the effects of different levels of temperature and light intensity on grapevine vegetative growth and bud fruitfulness, which includes the number and size of inflorescence primordia in primary buds.