Marlborough Sauvignon Blanc is a distinct style. Pungent. Really pungent. With the magical combination of crisp green notes and ripe tropical overtones. Supported by fresh, crisp acid, generous palate weight and a touch of complexity. It’s delicious. Refreshing. And loved by the masses.
Sauvignon Blanc is one of the few varieties where the global benchmark is set outside of its native land. And, set in the New World. (Malbec and Zinfandel could be considered others). The benchmark for Chardonnay and Pinot Noir is Burgundy. For Syrah it’s the Rhone. Cabernet and Merlot it’s Bordeaux. Riesling, Germany. Nebiolo, Piedmont. Sangiovese, Tuscany. And so on and so on.
But, Sauvignon Blanc is Marlborough. New Zealand. (You might say Mendoza for Malbec and California for Zinfandel)
So, why is Marlborough Sauvignon Blanc so distinctive? To get into the real nitty gritty and science read Jamie Goode’s book The Science of Sauvignon Blanc. I discuss some of the salient points of the book below.
Methoxypyrazines and Thiols
A point emphasised in the book is that Marlborough Sauvignon Blanc has the same compounds as other Sauvignon Blancs from around the world–there’s no compound unique to Marlborough. However, levels of methoxypyrazines (think bell pepper) and thiols (think passion fruit) are much, much higher than elsewhere on the planet.
There are two thiols in particular than seem uniquely elevated in Marlborough Sauvignon: 3-mercapto-hexyl acetate (3MHA) and 3-mercaptohexan-1-ol (3MH). These two thiols are strongly correlated to tropical, passionfruit, and ‘sweaty sweet’ aromas.
It seems thiol production is stimulated as a sort of defense mechanism by the berries after they’ve been wounded–like when they get bashed about by a machine harvester.
Due to its remoteness, lack of readily available labour, and cost, Marlborough was an early adopter of machine harvesting. Machine harvesting it turns out has a big influence on the aromatics of Sauvignon Blanc. There are up to ten times more thiols in machine picked fruit compared to hand harvested fruit.
But it’s not just machine harvesting that makes Marlborough Sauvignon blanc so distinctive.
Marlborough has 30-40% higher UV than its equivalent latitude in the Northern Hemisphere. High UV is good for flavour and aroma development .
However, UV is also good for killing microbes in the vineyard. Less disease means less things like botrytis moderating varietal expression. That’s not to say there’s no disease in Marlborough but there’s significantly less disease pressure than other regions. This factor also contributes to Marlborough’s pure and intense expression of primary fruit characters.
Jamie Goode’s book also discusses the mutations that are believed to be occurring in the vines in New Zealand due to the high UV conditions. Since most vines are now propagated from New Zealand cuttings, it’s very likely that clones have developed that are unique to New Zealand.
Why does New Zealand have a higher UV count than elsewhere? There are three main reasons. Firstly, the earth is closer to the sun during the Southern Hemisphere summer than it is during the Northern Hemisphere summer. Secondly, New Zealand has a very low level of air pollution. Largely owing to its isolation, small population, a relatively small scale industry. Thirdly, the hole in the Ozone layer is situated right above NZ. Very bad for skin cancer rates but can be good for intense aromatics in wines.
Marlborough is blessed with a really low level of cloud cover. So lots of bright sunny days. This lack of cloud cover combined with cool air draining off the surround mountains also means night time is very cold. One reason Marlborough is able to achieve a good level of ripeness, seen in its elevated alcohol (13% would be typically) and generous palate weight, while being able to retain such a high level of freshness.
Marlborough also, generally, has a low level of rain fall, as it’s protected from prevailing weather from the south-west by the Southern Alps. This, along with the high UV (mentioned above) helps reduce the disease pressure.
There are many factors that make Marlborough Sauvignon Blanc such a distinctive style. Some are direct human inputs through various viticultural and winemaking techniques. And, some are due to the unique environment in which the vines are grown. Most, however, are still a long way from being fully understood.