By Petra Carter.

Take a spoonful of sugar. Take two. Or even three.

Nice? Not really.

But combine the sugar with something bitter (say coffee) and its sweetness is transformed into something delicious.  Take meringues, decidedly sickly on their own, but add something tart like raspberries and both sweet and sour tastes explode in your mouth.  Serve sweet peaches with salty feta, add a little peppery bitterness in the form of rocket, a little sourness in the form of vinaigrette, and you’ve discovered a gem.

How does this work?  Well, it¹s all because of the way we taste. Our taste buds perceive five basic flavours – sweet, salt, sour, hot and bitter. Six if you count the more recent umami, a flavour perhaps best described as savoury – the intense ‘mouth-filling’ taste you get from reduced chicken-stock, dried porcini and soy sauce, or Parmesan and Roquefort. Umami causes us to salivate, which in turn magnifies our tasting ability.

It was the Chinese who discovered long ago that when a dish contains a harmonious balance of some (or all) of these tastes, we perceive it as delicious because each flavour is intensified by the next and all our taste buds are satisfied at once (a bit like an Impressionist painting where complementary colours put side-by-side, create a vibrant effect… or the melodious bond of different notes that intensify each other in a piece of music).

Each of these flavours also affects our perception of the other – even a tiny amount of one can enhance the other in a miraculous way. Try some bread topped with jam – it¹ll taste of bread and jam.  Now butter your bread generously with salted butter and then add the jam… a delicious mingling of salty, sweet and crunchy has turned it into a delicacy.  A little squeeze of lime turns a relatively dull-sweet papaya instantly into a juicy fruit that oozes fresh sweetness.  Think also of the currently fashionable way of serving crème caramel with fleur de sel.

Experiment with other classics: see how salty ham accentuates the sweetness in a melon, or how the ubiquitous combination of sweet-and-sour (tomato ketchup, a Chinese takeaway, lemon-meringue pie, gooseberry jam) makes our mouths water…  and how a glass of fragrant sweet Muscat wine or sweet juicy pears bring out the delicious umami-saltiness of blue Roquefort cheese.  How come orange marmalade is such a winner? Because it combines the bitterness of the orange rind, the acidity of its juice with sweetness of sugar – it cannot lose.

Since flavours affect one another, they can also be used to alter a dish.  Add zest to an overly rich creamy pork dish by adding some lemon juice. The ‘mouth-puckering’ sensation of drinks that are high in tannin, like red wine or strong tea (cranberries, unripe bananas and walnuts are another example of this) also have a refreshingly ‘cleansing’ effect by cutting right through the richness of something that might otherwise be cloying.  See how a dry sponge cake is brought to life with some lemon or orange juice.  Bitterness both suppresses and balances sweetness (as bitter chocolate does with rich vanilla ice-cream) whereas saltiness on the other hand has the effect of sweetening its partner – as Parma ham does with a fig, and salty anchovies achieve with a sweet pepper.

Needless to say that if we apply some of this knowledge to our daily cooking, our meals would be a great deal more exciting.  And if this flavour combining becomes our intuitive way of ‘putting a dish together’ we could follow the seasons more easily, as we would simply buy what’s at its best and match it with its perfect ally.

But to create this symmetry of flavours we need to first embrace a broader sense of flavours – a peach is sweet of course, but sweetness can also come from shellfish or fresh garden peas, beets, sweet peppers or roast butternut squash.  Salt could be from anchovies, or capers, goats cheese, Serrano ham and chorizo, whilst the heat from chillies can also be found in mustard or radish, pepper, garlic, rocket or extra virgin olive oil.  And a dish can be soured not just with vinegar but also with wine, unripe tomatoes, lemon zest, apples or sorrel.

Aroma or fragrance which is thought to be responsible for as much as 80% of our perception of flavour, is also a reliable guide to deliciousness ­ if something smells yummy, it is likely to taste good too.  Smell is therefore generally our first sensuous indication as to what we¹re about to taste.  A delicious smell makes us salivate in preparation for the tasting.

Not quite a flavour, but equally essential in making up a dish, is texture. Creamy or pureed dishes are usually associated with comfort whereas we normally think of crunchy or crispy foods as more ‘fun’ foods (crisps, nachos, nutty biscuits etc). Dishes that are overall smooth-textured highly benefit from the addition of a little crunch: a handful of chopped nuts, some crispy croutons, crunchy salad leaves, crusty bread all add a bit of cheer. Coarsely chopped praline or amaretto biscuits do the same to a soft creamy dessert. If only to reduce the monotony!

Another mouth-feel factor that greatly affect how we experience a dish is temperature. Coldness of a dish can suppress flavours, heat can enhance them, yet a tepid dish gives the most flavour. Also remember the climatic temperature factors – warm food on a cold winter¹s generates comfort, whereas a salad or cold soup on a hot summer¹s day refreshes.

There is also another sense of hotness, one we usually perceive as ‘spiciness’ or ‘piquancy’ – as in chillies or cayenne pepper. Chillies contain capsaicin, an irritant that heightens our sense of taste by exciting the palate. It also stimulates our sense of pleasure (at the same time raising our body temperature) by promoting the production of endorphins – the body¹s natural painkillers.

And lastly, for a dish to be successful it must also seduce our eyes.

Attractive food draws us in and gets us in the mood for eating and tasting. We eat, after all, mostly for pleasure.  For if we ate for sustenance alone, we would surely by now survive on nutritive pills and water alone…

If you want to learn more about cooking with flavours, check out Petra’s cookery weekends on www.petracarter.com.