The grape harvest temperatures as well as oenological practices such as skin contact, effect Sauvignon Blanc wine quality. The majority of Sauvignon Blanc wines produced in South Africa do not have the typical varietal characteristics, mainly as a result of climatic effects. There is a need to optimize the aromas by means of viticultural and/or oenological practices. Much success has already been achieved by means of canopy management. The aim of the present study was to utilize grape temperature and yeast strain to enhance the typicity and quality of Sauvignon blanc wine. For this purpose grapes that historically yield neutral wines were used. Grape temperatures of 10°C and 25°C at harvest and fermentation with different Saccharomyces cerevisiae yeast strains (VIN13, VIN7, NT116 and NT7) were investigated over three seasons (1998, 1999 and 2000). Grapes at 10°C yielded significantly higher quality wines with higher acetate and ethyl ester concentrations than grapes at 25°C. Differences between seasons were observed. All of the yeast strain appeared to be quality enhancing. A few strain, however, stood out. Strain NT 116 was associated with the production of the highest ester and lower alcohol levels. Some of the highest quality wines were produced by strain NT7. Strain VIN7 was associated with the production of the highest green pepper/asparagus nuances in each of the three seasons. Sensory ranking of the wines confirmed individual evaluation results to a great extent. In general, choices were affected by grape maturity, grape temperature, location and season, which affected wine composition. Under the condition of this study, grape temperature at harvest and yeast strain had a significant effect on Sauvignon blanc wine composition and quality. Grapes should be cooled to at least 10°C or lower directly after crushing. However this technology should be further investigated. Yeast strain should be carefully selected.

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