Wine is one of human's most complex food flavours

Skeptics raise their eyebrows when the wine snobs reel off tastes from a glass  of wine: "a hint of leather with a soupçon of heather and lavender..." Surely these frauds are just making this all up.

I won't attest to the veracity of some wine enthusiast's tasting notes. Sometimes they do seem a bit far-fetched. But, as wine is one of the most complicated of all food tastes, there's reason to believe they aren't just baffling you with their gastronomic skills.

Humans can taste, and particularily smell (human sense of smell is much more acute than our sense of taste), over 1800 different flavour compounds, all with scary-sounding chemical names. All foods carry a portion of those 1800 flavours. Some, such as salt, are very simple, including just a few of those flavour compounds. Some, like chocolate, are very complex. Wine grapes are among the most complex tasting foods in the world, carrying up to 1100 of those flavour compounds. So when you taste a rich glass of ultra-ripe white wine and the flavour of pineapple comes to your mind, it's because the flavour compounds that make a pineapple taste like a pineapple are also present in the wine. Or when you taste chocolate in a rich red Cabernet, it's because the wine also has those compounds that make chocolate taste like chocolate.

How do those flavours get in there? The winemaker doesn't put pineapple or chocolate flavours into the wine, does she? No, some flavours occur naturally in the winegrapes, and some are coaxed out of the wine by various means during the wine-making process.

As grapes ripen, they move through a range of flavours. White winegrapes begin very tart, full of citrus flavours--lemon, lime and grapefruit zest. Then they move through tree-fruit flavours--apple and pear. Then stone fruit--apricot and peach. And finally tropical fruit--coconut, melon and pineapple. Red winegrapes go through a similar transition--cranberry and rhubarb, through berry fruits to plums prunes and raisins. But in any bunch if grapes there are more ripe berries and less ripe berries, depending on where the berry is in the bunch, where the bunch is on the vine, and even where that vine is in the vineyard.  So when the grapes are harvested, the berries are all at different levels if ripeness. That means that in a harvest of pinot gris grapes, there are some berries that taste of lemon, some of apple, and some of melon. The resulting blend then is a delightful mélange of flavours right across the ripeness spectrum. That's how the initial juice gets that complex flavour.

Then in the winery, all sorts of treatments add to this complexity. Fermentation itself alters the flavours. Different yeasts are chosen to enhance certain aspects of the flavour. Different enzymes are added to break down the vegetable parts of the fruit and enhance certain parts of the flavour. Great winemakers conduct these yeast strains and enzymes to breed complexity into the flavour the way great conductors direct different sections of the orchestra, with the same intent--to create a complex harmonious whole.

Then there's how the fermentation is conducted. When yeast turns sugar to alcohol, one of the by-products is heat. A winemaker can conduct a cool fermentation, chilling the must as it ferments, to protect apple and citrus flavours, or a hot fermentation, which will enhance the "cooked" flavours, like prunes and fruit jams.

Next there's whether the winemaker lets the wine go through secondary fermentation or not. That's when the acids in the wine are converted from one type to another: malic acid, which favours apple (malus in Latin), to lactic acid, the acid that's present in milk products. This is called "malo-lactic" fermentation and it can drastically change the flavour of the wine, reducing tart green acidity and enhancing butteriness in the wine. Malo-lactic fermentation is usually allowed to occur in most red wines and in oaked whites such as Chardonnay.

Finally there is oak. Many red wines are aged in oak barrels which are toasted during manufacture. Or the wines are flavoured with oak chips during the aging process. At Morning Bay we use a combination, aging the wines in oak barrels, and adding oak chips at various times during the winemaking process. Like maple sap.

Oak sap, much like maple, contains a certain portion of sugar, and when the wood is toasted that sugar takes in flavours of caramel, vanilla, cocoa, coffee and other "toasted" flavours. Wine aged in toasted oak barrels, or treated with oak chips, takes on these toasted flavours. The result is another level of flavour complexity.

So you see that when you wine snob friend goes on about all those things he smells and tastes in a wine, he may not be just blowing smoke. However you don't need to be able to identify all those flavours to get full enjoyment out of the wine. All you have to do is swirl, sniff, sip, and enjoy! The wine does the work for you.

Cheers!

Keith

Keith Watt is proprietor of pendrr Island's Morning Bay Vineyard.