Apart from above-mentioned analyses requirements, local legal analyses requirements also need to be complied with. These requirements are usually published as regulations in the Government Gazette and its compliance is controlled by the South African Wine Industry Information and Systems (Sawis) and the Department of Agriculture. It usually includes minimum and maximum concentrations of alcohol, sugar, volatile acidity (VA), sulphur dioxide and pressure.
Local alcohol requirements (% per volume)
Natural wines (unfortified wines)
like white, rosé, red, perlé and sparkling wines must have an alcohol concentration between 4.5 and 16.5.
Fortified wines (wines with added alcohol)
like jerepigos, port and sherry must have an alcohol concentration between 15.0 and 22.0.
Local pressure requirements (kilopascal) (kPa)
Most motor tyres have a pressure of 200 kPa
Perlé wine: 75 to 300.
Sparkling wines: More than 300.
Local sugar requirements
Residual sugar (RS) in g/ℓ: Total acid (TA) in g/ℓ
Extra dry: 2.5 or less.
Dry: 5.0 or less or 9.0 or less, if TA is less than 2 lower than the RS.
Off dry: More than 5.0, but equal to or less than 12.0 or 18.0 or less, if the TA is less than 10 lower than the RS.
Semi-sweet: More than 5.0, but less than 30.0.
Late harvest: 20 or more.
Noble late harvest: More than 50.
Sweet natural: More than 20.
Local volatile acidity (VA) requirements (g/ℓ)
Noble late harvest and wine from sundried grapes: 1.8 or less.
Bulk wine for export: 0.8 or less.
Other wine: 1.2 or less.
Local total sulphur dioxide requirements (mg/ℓ or ppm)
Red wine with RS less than 5: 150 or less.
White wine with RS less than 5: 160 or less.
Natural wine with RS more than 5: 200 or less.
Noble late harvest and wine from sundried grapes: 300 or less.
If wine is sold with indications of the grape cultivar used for it, the origin of the used grape or the vintage grapes which were used must, in addition to the above analytical requirements, also comply with certain composition percentages. These composition requirements are prescribed by the Wine of Origin scheme.
Cultivar, origin and vintage requirements (%)
Cultivar: At least 85% if a single cultivar is indicated.
Origin (region, district, ward, estate or single vineyard): 100% of the indicated origin.
Vintage: At least 85% if a single vintage is indicated.
In order to export local wines, an export certificate of the Department of Agriculture is required and the countries exported to, also have certain requirements to be complied with.
Although all the above requirements can be complied with, the consumer will only buy the wine if it meets its expectations. Different factors like the wine type (white, red, perlé or sparkling), the age of the wine, wood character, sugar-acid ratio, sweetness degree and consistent quality, will determine whether the consumer likes the wine and will possibly buy it again.
The blending of wine does not only consist of the mixing of wines, but is a well-planned execution to ensure that above-mentioned requirements are met. It is consequently one of the most important tasks of a winemaker.