The effect of bottle ageing on the antioxidant activity of Pinotage, Cabernet Sauvignon, Chardonnay and Chenin blanc wines, using the 2,2'-azino-di-(3-ethylbenzothialozine-sulphonic acid) radical cation (ABTS•+) and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH 0 ) scavenging assays, was determined. Storage at 0°C, 15°C or 30°C for a period of 12 months resulted in a significant (p ~ 0.05) decrease in both the total antioxidant activity (TAAAnTs and TAAoPPH) and the total phenol content of the wines. The antioxidant potency of the total phenols of most of the wines, which is a ratio of antioxidant activity to the total phenol content, also decreased. The total anthocyanins in the red wines decreased significantly (p ~ 0.05) over 12 months except for storage at 0°C, while the flavanol content of the Pinotage, Cabernet Sauvignon and Chardonnay wines increased up to nine months storage with a subsequent decrease to 12 months. The flavonol content of all the wines decreased, while only minor changes in their hydroxycinnamate content were observed during the storage period. Understanding the complexity of these reactions may provide clues for stabilising especially red wines to preserve the antioxidant activity without losing the beneficial effects of colouring and flavour development during bottle ageing.The ability of wines and other foods to prevent free radical-mediated diseases has been investigated recently (Halliwell & Gutteridge, 1990;Davies, 1995;Leake, 1998). The possible health-promoting properties of wine are related in part to phenolic compounds and their ability to act as antioxidants (Kinsella et al., 1993). In view of the greater health awareness among the public in terms of their diet, the antioxidant content or antioxidant potential may become a factor in determining the acceptability and marketability of wine and other foodstuffs. More information is, however, needed on the effect of technological factors and storage conditions on the antioxidant parameters of wine prior to consumption. Various technological factors relating to vineyard and vinification practices (Hurtado et al., 1997;Pellegrini et al., 2000), as well as the effect of cultivar (De Beer et al., 2003), were shown to alter the phenolic content and antioxidant activity of red and white wines.Bottle ageing is important for the improvement of red wine quality (Somers & Pocock, 1990). For white wine it can contribute to quality defects such as non-enzymatic browning and over-maturation, although some white wines may derive shortterm benefit from the development of a characteristic bottle bouquet (Marais & Pool, 1980). Conflicting reports regarding the effect of ageing on the antioxidant activity of red wines have been *Corresponding author: E-mail address: joubertl@arc.agric.za published. Manzocco et al. (1998) and Okuda et al. (2002) reported a decrease in 2,2-diphenyl-1-picrylhydrazyl radical (DPPH 0 ) scavenging activity for older wines based on the scavenging rate and total radical scavenging activity, respectively. Larrauri et al. (...