A wine that bears the certification seal has been checked at each stage of its production -- from vineyard to bottle -- by an official from the Wine and Spirit Board. When you buy a bottle that has been certified you know that all the information contained on the label is reliable and correct.
A typical label on a bottle of certified wine will include the vintage year. This means that the grapes used in the making of the wine were harvested in the year indicated.
A certified label could also indicate the area of origin, stating that the grapes were grown in the Stellenbosch region, the Robertson region or the Coastal region or whatever the case may be. The smallest unit of origin that may be specified is an estate, in which case the label might also say: estate bottled, indicating that the wine was grown and bottled on that particular registered wine estate.
Finally, the label could state the grape cultivar or variety from which the wine was made. For example, Cabernet Sauvignon, Shiraz, Pinotage, Pinot Noir and Merlot in the case of red wines. Or Chenin Blanc, Chardonnay, Sauvignon Blanc, Rhine (or Weisser) Riesling in the case of whites.
In some cases the law states that, where a cultivar is specified on the label, the wine should contain a specified minimum percentage of that cultivar in the blend. A wine labelled Cabernet Sauvignon, for example, must contain at least 75% of Cabernet Sauvignon juice. This is because some cultivars (and Cabernet is a typical one) are improved by the addition of a small quantity of another grape type.
Not all wines are certified, which is why the cheaper commercial blends are given brand names rather than cultivars. Some very well known wines, like the legendary Tassenberg, are made from grapes harvested in several regions (and even imported from other countries) and picked in several years. Being uncertified does not necessarily imply that the wine is inferior. It does mean, however, that the label will not contain as much accurate information about the contents as one would expect from that of a bottle of certified wine.The label on an uncertified bottle of wine may not include a vintage year, a cultivar or the area of origin from which the wine comes.