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The Argentine official method to determine the content of reducing sugars in musts and wines is the Causse Bonnans Fehling method. This method requires a sample treatment to obtain a decolorized and clear solution. Activated charcoal and lead acetate are used for this procedure. The effects of lead poisoning in humans, animals and the environment are known, so it is necessary to minimize their use to achieve sustainable production. Reducing sugars were analyzed in 149 wines and 67 grape musts. For each sample, two different treatments were used: a) 5 mL of lead acetate at 25% and 0.5 g of activated charcoal and b) adding 5 mL of distilled water and 0.5 g of activated carbon. The data were processed by performing simple linear regression analysis. Lead acetate can be eliminated in the pretreatment of must and wine samples to determine reducing sugars by Fehling Bonnans Causse method. This modification of the original technique eliminates the use of lead salts and pollution involved, without faults in the measurement of the reducing sugars. [ABSTRACT FROM AUTHOR]

The IPCC has predicted changes manly in temperature, rainfall and extreme events. Rises in earth surface temperature of 0.6 ± 0.2°C has been already detected during 20th century. Plant physiology, productivity, and phenological cycle depend on climatic conditions. In this work meteorological series comprising 50 years of three productive oasis (Mendoza, Argentine) were analyzed, through climatic and ecological indexes. Were compared statistically in two decades of the whole series (a beginning one and a final one), and their variation over time was analyzed by lineal regression. Comparative analysis of the two decades showed different changes according the studied zone. The East zone showed the highest number of indexes which might affect viticulture suffering variation. On the North and South zone, the number of indexes showing variation had been lower compared to the East zone. To know the climatic changes that occurred at local level, their magnitude on the last 50 years and their tendency will allow to evaluate their possible impacts on vine physiology, phenology modification, sugar accumulation and phenolic compounds as well as to elaborate new assays and strategies in order to mitigate their negative effects. [ABSTRACT FROM AUTHOR]