About 20 years ago, white wines from the Marlborough region of New Zealand hit world markets. These cool-climate sauvignon blancs were crisply delicious. 'Wow,' said the world. Since then, vineyards have crept even further south: they are now making wine in the middle of South Island; these are the most southerly vineyards on Earth. Gieson Winery is at Burnham, outside Christchurch. For reasons inexplicable to anyone with access to an atlas, the label on their 98 sauvignon blanc says 'Marlborough'. On the back label, there is a map showing the place is located about 300 kilometres south of there. But who is quibbling? Not me, once I tasted this addition to the Kiwi portfolio of clean, sharp whites. Brought in by Wine 'n' Things (fax: 2554-5369), it sells for $102. Mother Nature designed the sauvignon blanc grape specifically to make wines which go with seafood. The three brothers Giesen have given her a helping hand, adding their considerable wine-making skills to the natural flavour of the grape. This is a lovely drink, blooming with ripe gooseberry and melony flavours. It is also as sharp as a well-honed razor. The Giesens are a German family who emigrated to the South Pacific in 1979. They owned wineries in Germany and thought the Christchurch region was a new Rhineland. Naturally, they planted riesling. They are now planting a wide variety of grapes, including pinot noir; mild, flavoursome Christchurch reds made by a number of wineries are gaining a cult following in world markets. The trouble is the production is so small there is not enough to reach world markets.