by Brendan Smith & Benoit Divol | 1 May, 2017 | Oenology research, Winetech Technical
How can you avoid the enigmatic scavenger, Brettanomyces bruxellensis, in your wine? The characters A horrible crime has been committed! An innocent bottle of wine has been infected. Those detestable aromas of barnyard, horse sweat, leather, cloves, vinegar and...
by Natasha Pretorius, Lynn Engelbrecht & Maret du Toit | Oenology research, Winetech Technical
Various factors influence the amount of diacetyl, acetoin and 2,3-butanediol produced during fermentation impacting the buttery aroma. Malolactic fermentation (MLF) is a secondary fermentation carried out by lactic acid bacteria (LAB). This process can occur...
by Jose Luis Aleixandre-Tudo, Mihaela Minhea & Wessel du Toit | Oenology research, Winetech Technical
The importance of phenolic compounds on wine quality require methods that accurately measure the tannin content. Tannins are phenolic compounds that play an important role in the astringency perception of red wines. Tannins also are very complex molecules with...
by Pia Addison, Francois Halleen, Wessel du Toit & Hélène Nieuwoudt | Oenology research, Viticulture research, Winetech Technical
1. Ecology and management of Lobesia vanillana in vineyards Researcher: Pia Addison Lobesia vanillana is a pest species that was recently confirmed to attack wine grapes in the Western Cape. Grapes have not been listed as a host for this pest, therefore its ecology in...
by Phillip Minnaar, Neil Jolly, Zama Ngqumba & Valmary van Breda | 1 Apr, 2017 | Oenology research, Winetech Technical
Introduction Non-Saccharomyces yeast species contribute to the aroma and flavour of wine due to metabolic products resulting from their growth. These metabolites include terpenoids, esters, higher alcohols, glycerol, acetaldehyde, acetic acid and succinic acid. The...
by Debra Rossouw & Florian Bauer | Oenology research, Winetech Technical
Introduction A prominent goal in global wine research is the reduction of ethanol levels in wine, without the use of physical alcohol removal methods such as spinning cone columns and reverse osmosis (Howley & Young, 1992; Pickering, 2000). This research is...
by Wessel du Toit & Pia Addison | Oenology research, Viticulture research, Winetech Technical
1. Modelling colour stability and ageing potential in SA red wines Researcher: Wessel du Toit The evolution of red wines in terms of certain sensorial characteristics as influenced by phenolic compounds is not well known. The question remains whether winemakers agree...
by Anton Nel | 1 Feb, 2017 | Oenology research, Winetech Technical
When white wines with the potential to pink are exposed to oxygen, the phenomenon known as pinking occurs. It is common in Sauvignon blanc, but also occurs in Chardonnay, Colombar, Chenin blanc and Viognier. Literature exists about the possible compounds and...
by Francois van Jaarsveld & Francois October | Oenology research, Winetech Technical
Introduction Some white wines show premature ageing effects after relatively short bottle ageing, although there is nothing wrong with the vinification process and the levels of heavy metals (specifically iron and copper) are not higher than legally permitted. The...
by Hans André Eyéghé-Bickong, Philip Young & Melané Vivier | 1 Jan, 2017 | Oenology research, Winetech Technical
This review presents a summary of the chromatographic methods that have been developed and optimised to accurately profile and quantify grape metabolites. The goals were to establish routine methods that are suitable for samples sizes as low as a single berry, as well...
by Hélène Nieuwoudt | Oenology research, Winetech Technical
The objective of this study was to investigate the impact of commercial MLF starter cultures on wine composition, the subsequent aroma and flavour characteristics and the potential impact on consumer preferences. In wine style research there is a distinct focus on...
by Reckson Mulidzi | Oenology research, Winetech Technical
Introduction The wine industry produces large quantities of wastewater associated with washing operations during grape harvesting, pressing and first fermentation phases of wine processing (Mulidzi, 2007). Traditionally wastewaters from wineries and distilleries have...
