Effect of Canopy Microclimate, Season and Region on Sauvignon blanc Grape Composition and Wine Quality

Juice and Wine Quality Responses of Vitis vinifera L. cvs. Sauvignon blanc and Chenin blanc to Timing of Irrigation during Berry Ripening in the Coastal Region of South Africa

“…This result was to be expected since ambient air temperature of the ripening period, which can affect the aroma intensity and flavour composition of Sauvignon wines (Marais et al, 1999;Bonnardot et al, 2000), did not differ between seasons (Myburgh, 2005). Mean air temperatures during the ripening period were also comparable to the long term mean of 27.9°C.…”

“…The possibility that the higher yields during this particular season contributed to the effect of irrigation should not be ruled out. Although lower water stress could have negative effects on this particular aroma, the effect of water deficits might not be as pronounced or consistent as the effect of ambient temperature due to differences between localities (Marais et al, 1999) or seasons (Bonnardot et al, 2000). As in the case of Sauvignon blanc, the fermentation bouquet (guava flavour) of Chenin blanc did not differ between seasons ( Table 4).…”

Quantitative Survey of 3-alkyl-2-methoxypyrazines and First Confirmation of 3-ethyl-2-methoxypyrazine in South African Sauvignon blanc Wines

“…It is generally accepted that grapes grown in hot climates often metabolise most of their malic acid before harvest, whereas grapes grown in cooler climates retain most of their malic acid into maturity (Jackson, 2000). As a result, a relatively high wine malic acid concentration may indicate that the grapes were harvested earlier or were grown in cool conditions, both of which are also factors that are associated with higher levels of wine MPs (Hashizume & Samuta, 1999;Marais et al, 1999;Roujou de Boubee et al, 2000;Marais, 2004;Sala et al, 2004;Ryona et al, 2010). This hypothesis is supported by a study that reported that the breakdown of malic acid and IBMP in grapes during ripening is highly correlated (r 2 of 0.90 to 0.99), irrespective of soil type, grape variety or vintage (Roujou de Boubee et al, 2000).…”

“…As a consequence, Sauvignon blanc wine possessing the typical green pepper or vegetative aroma is sensitive to production factors such as geographical origin Marais et al, 1999), mesoclimatic conditions Marais et al, 1999;Falcăo et al, 2007), canopy microclimate (Marais et al, 1999;Sala et al, 2005), water availability (Sala et al, 2005), solar radiation (Hashizume & Samuta et al, 1999;Sala et al, 2004) and time of harvesting (Ryona et al, 2010). Marais et al (1999) reported that canopy microclimate plays a particularly important role in determining grape MP levels and that exposure to solar radiation, as manipulated by canopy management, has a more prominent effect than climatic temperature alone. Viticultural practices (Marais et al, 1999;Maggu et al, 2007) and the yeast strain used (Pickering et al, 2008) also affect wine MP concentrations.…”

“…Marais et al (1999) reported that canopy microclimate plays a particularly important role in determining grape MP levels and that exposure to solar radiation, as manipulated by canopy management, has a more prominent effect than climatic temperature alone. Viticultural practices (Marais et al, 1999;Maggu et al, 2007) and the yeast strain used (Pickering et al, 2008) also affect wine MP concentrations. Moreover, possible infestations with lady beetles may also contribute MPs to affected wines.…”