Influence of harvesting technique and maceration process on aroma and phenolic attributes of Sauvignon blanc wine.

Sauvignon blanc wines are characterised by their varietal aromas and low phenolic content. Mechanical harvesting has been shown to increase several varietal aromas. Likewise, maceration techniques have produced increases in phenolic content and antioxidant activity, but these can also alter tactile attributes and sensory profiles. Mechanical harvesting and cryogenic maceration were used in combination to produce a Sauvignon blanc wine with increased phenolic content and antioxidant activity, while showing a similar sensory profile to control wines. Phenolic profiles of the wines showed differences between the harvesting and maceration techniques. Mechanical harvesting contributed to decreases in phenolics through reaction with oxidative radicals. Cryogenic maceration increased phenolics and antioxidant activity. Cryogenic maceration also increased the levels of several varietal aromas, for Sauvignon blanc wines made from both hand-picked and from machine-harvested fruit. Furthermore, cryogenic treatment of hand-picked fruit increased varietal thiols to levels similar to machine-harvested control wines.