Mary-Lou Nash CWM and Lizette Tolken CWM recently attended the Black Oystercatcher Secrets of Sauvignon tasting at Caroline’s Fine Wines in Cape Town. The same tasting as Cathy White attended, but in a different time and place.
Black Oystercatcher Wines decided to test the relationship between their Sauvignon Blanc and the soil the vines grow in. In 2017, the grapes were hand-selected at optimal ripeness from three different soil types, Quartzite, Iron Ferricrete, and Broken Shale, and made three wines from the different soil types. The wines were then vinified in the same way before storage in old 300 litre barrels before bottling.
They market their wine as quality cool climate wines with a distinctive minerality. But what exactly is minerality in wine?
Unfortunately, there is no real agreement. Opinions differ as to whether grapes absorb minerals from the soil and if you can taste them. The mineral elements in wine are tiny, so the chance of tasting them is slim. Scientists might say minerality comes from sulphur or fusel compounds. Many producers see it as an expression of the terroir. Interestingly, for winemakers minerality is usually positive, while consumers do not always see it as a positive attribute.
Maybe minerality is simply another wine descriptor, much like flinty, salty and earthy are. That said, minerality, wherever it may come from, was a perfect descriptor for the three different Sauvignon blancs we tasted. The Quartzite wine was described as gunflint, the Iron Ferricrete having strong earthy notes, and the Broken Shale showing oyster shell and salinity.