Ultraviolet Radiation

or UV radiation

Appears in
Oxford Companion to Wine

By Jancis Robinson

Published 2006

  • About

ultraviolet radiation or UV radiation, radiation of shorter wavelength (< 400 nm) than so-called visible sunlight, and which is very damaging to all life because of its mutation-inducing properties. phenolic compounds absorb ultraviolet radiation, and levels of quercetin in grape berries are related to ultraviolet exposure. It is proven that ultraviolet exposure increases levels of phenolics and therefore colour in red wines, which can be an advantage of vineyards at high elevation, and those closer to the ‘ozone hole’ over the Antarctic. This raised the intriguing possibility that the more southerly regions of the southern hemisphere have a wine quality advantage over northern hemisphere wine regions due to higher UV levels.