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The potent aroma compound rose oxide was quantified in several white wines by a headspace solid-phase microextration stable isotope dilution assay (HS-SPME-SIDA) and the enantiomeric ratios of the cis diastereomers were determined by enantioselective capillary GC. The most odor-active stereoisomer (23)-cis-rose oxide was detectable in all investigated white wines ranging from 0.2 to 12 microg/L. However, its contribution to the overall aroma in some white wine varieties can be neglected as indicated by a low odor activity value (OAV). The highest concentrations were found in Gewürztraminer wines, confirming the importance of rose oxide as a varietal aroma compound in this variety. Surprisingly, the enantiomeric ratio of cis-rose oxide in all investigated wines was substantially lower than in nonfermented musts and in some wines almost racemic cis-rose oxide was detected. Fermentation studies with a model must that contained deuterated water revealed that yeast is capable of reducing the precursor 3,7-dimethyl octa-2,5-dien-1,7-diol (geranyl diol I) yielding 3,7-dimethyl-5-octen-1,7-diol (citronellyl diol I) that gives rise to cis- and trans-rose oxide after acid catalyzed cylization. The deuterium labeling pattern of the resulting rose oxide stereoisomers and a clearly detectable kinetic isotope effect indicate that at least two different reductive pathways in yeast exist that yield cis-rose oxide with different enantiomeric ratios altering the genuine enantiomeric ratio in grape musts. The presence of (+)-cis-rose oxides in wines can therefore be attributed to the reductive yeast metabolism during fermentation. This observation corroborates recent findings that the modification of terpene derived varietal aroma is an integral part of yeast metabolism and not only a simple hydrolytical process.

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The issue of energy poverty or the lack of access to modern energy has received increasing attention in the development literature, including specific reference in the UN Millennium Development Goals (MDGs). Measures based on just energy expenditures (‘energy burden’) are shown to be rather inadequate when identifying energy-poor households. This paper uses an access-adjusted energy poverty measure that allows for varying energy efficiencies and access to different fuel types used by sampled households from a 2008/9 Department of Energy survey. Taking three pre-assigned thresholds of household energy use among LSM1-LSM3 households, all the South African provinces are mapped showing spatial incidences of energy poverty for electrified households. It is proposed that these access-adjusted indicators are methodologically more robust and informative for policy than conventional, purely expenditure-based indicators.

Energy provision and the role it plays in poverty alleviation is well documented. South Africa has an ambitious poverty alleviation program of halving 2004 poverty levels by 2014, which demands an increase in the provision of energy to both urban and rural impoverished areas. Yet the country has no energy based poverty indicators to guide such policy. This paper attempts to fill that gap by developing reliable, theoretically rigorous energy based indicators from extant data gathered in the 2005 South African household survey. An end-use and access-adjusted energy based poverty indicator compares favourably with other poverty variables using correlation analysis. We find that such indicators can assist government policy in meeting poverty targets such as that outlined by the Accelerated and Shared Growth Initiative for South Africa (AsgiSA).

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Water is a vital natural resource, demanding careful management. It is essential for life and integral to virtually all economic activities, including energy and food production and the production of industrial outputs. The availability of clean water in sufficient quantities is not only a prerequisite for human health and well-being but the life-blood of freshwater ecosystems and the many services that these provide. Water resource intensity measures the intensity of water use in terms of volume of water per unit of value added. It is an internationally accepted environmental indicator of the pressure of economic activity on a country's water resources and therefore a reliable indicator of sustainable economic development. The indicator is particularly useful in the allocation of water resources between sectors of the economy since in waterstressed countries like South Africa, there is competition for water among various users, which makes it necessary to allocate water resources to economic activities that are less intensive in their use of water. This study focuses on economy-wide changes in South Africa's water intensity using both decomposition and empirical estimation techniques in an effort to identify and understand the impact of economic activity on changes in the use of the economy's water resources. It is hoped that this study will help inform South Africa's water conservation and resource management policies.