Technical Yearbook 2023

MARCH

Effect of light exposure on bottled Sauvignon blanc wine By Carien Coetzee

Introduction Bottled wines are exposed to various light sources, such as natural sunlight (during transport and shipping operations) and artificial light (wine shops and supermarkets). Exposure to light can potentially induce significant changes to a wine’s composition mainly due to photochemical oxidation reactions resulting in changes in aroma and colour. 2-5 The question is whether adding antioxidants such as sulphur dioxide and glutathione will prevent some light-induced oxidation reactions from occurring, thereby preserving the wine’s A recent study 1 aimed to investigate the effect of light exposure on the chemical composition and sensory perception of a bottled Sauvignon blanc wine while simultaneously testing the impact of added antioxidants, sulphur dioxide and glutathione.

composition and quality. Materials and methods

A young Sauvignon blanc wine from Chile’s Maule region was manually bottled into 375 mL clear glass bottles and closed with low oxygen transfer rate stoppers. The bottles were stored in a vertical position at 30°C for three months, either exposed or

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TECHNICAL YEARBOOK 2023