One of the more confusing bits of childhood science education is learning that there are only four or five tastes (textbooks have been slow to add the fifth taste, commonly called umami or savouriness, even thought it was discovered over a hundred years ago).* How can all the flavours, from chocolate to broccoli, be broken down into just five simple components – sweet, salty, sour, bitter and savoury?
In molecular gastronomy, the scientific study of cooking, flavour is broken down into two parts: aroma and taste. The aroma is the part of the flavour sensed in the nose, and taste is what’s experienced by the tongue. Herbs and vegetables often have a lot of aroma, but little taste – you can test this by making a vegetable stock or soup without salt (nor other strong tasting ingredients like sugar or soy sauce). The resulting soup smells good, but its flavour is weirdly unsatisfying.
The sense of taste evolve as a way to quickly check the nutritional content of food, so it’s no surprise that each of the five main tastes corresponds fairly closely to a nutrient (or, in the case of bitterness, a toxin):
|Sweet||Sugars (glucose, fructose, sucrose…)||Sugar and carbs|
|Salty||Sodium and similar ions||Salt|
|Sour||Acids||Ripe fruit (in small amounts), unripe fruit (in large amounts)|
|Bitter||A wide range of molecules, mostly poisonous (there are at least 5 different types of bitter taste bud)||Fresh veg (in small amounts), inedible or toxic veg (in large amounts)|
These aren’t necessarily all the tastes – there’s also a distinct metallic taste, and the food chemist Hervé This (whose writings influenced this post a lot) thinks the taste of liquorice (glycyrrhizic acid) is also distinct – but these are the big five that are important in cooking. Alongside these are sensations like astringency (the dry sharpness of red wine or black tea, caused by tannins), coolness (the cold, numbing feeling you get from mint or menthol) and pungency (the fiery sensation of chillies and horseraddish) – some cultures classify these as tastes in their cuisine, but they aren’t triggered by specific taste buds.
With this, we can build our periodic table of tastes. Any dish or meal consists of a combination of these tastes, plus some relatively tasteless starch (bread, rice, potatoes…) and some herbs, spices and pungent vegetables (such as garlic, onions or chillies) for aroma and those other semi-tastes. By breaking down popular meals into these elements, we can see how they work.
|Sweet (Sw)||Salty (Sa)||Sour (So)||Bitter (Bi)||Umami (Um)|
|Seasoning (s)||Sugar, honey||Salt, salmiak||Vinegar, lemon juice, tamarind||Fenugreek, tumeric||Soy sauce, Worcestershire, Yeast|
|Vegetable (v)||Carrots, peppers||Seaweed||Pickles, kimchi, sauerkraut||Leafy vegetables, bitter gourd||Mushrooms, beans, tomatoes|
|Fruit (f)||Apples, bananas, strawberries||Rare1||Citrus fruit, many berries||Crabapples, sloes, dark chocolate||Nuts, fruit pickles and chutneys|
|Meat (m)||Rare2||Bacon, gammon, seafood||Pickled meats||Kidneys, liver||Most meat|
|Dairy (d)||Mild cheese, cream||Butter, crumbly cheese||Yoghurt, sour cream||Mature cheese (cheddar)||Strong cheese (parmesan, stilton)|
|Beverage (b)||Fruit juices||Rare3||Citrus juices, fermented drinks||Bitters, tonic, beer with hops, tea||Green tea, Bovril|
1 There aren’t many salty fruit, but some fruit that grows by the sea, such as sea buckthorn or the Australian pigface sea-fig, do have a salty taste.
2 There isn’t much naturally sweet meat, but honey is often used to sweeten it either as a marinade or a coating on a roast. Sweetbreads (the glands of animals) are reputedly sweeter tasting than normal meat, although I’ve never tried them.
3 Saltiness isn’t normally prized in drinks (since drinking salt water makes you sick), but salt is added to some milk drinks, such as lassi.
Spaghetti bolognaise, for instance, consists of beef (an umami meat (Umm in the table above)) or mushrooms (an umami vegetable (Umv)), plus tomatoes (another umami vegetable (Umv)), and is topped with parmesan (an umami dairy (Umd)), plus onions, garlic, herbs and pasta. All the main ingredients are umami, and they combine into a extremely delicious savoury dish – it’s no coincidence that Lee & Perrins advertise their Worchestershire sauce (yet another umami seasoning) as ideal for spag bol.
Combining similar tastes like this adds depth to a meal, while combining different tastes adds breadth.
Sweet and sour is combination that goes famously well together (from an evolutionary perspective, the sweet and sour taste combination are associated with fruit that is ripe but not overripe). The most obvious sweet and sour dishes (classic Chinese takeaway meals, or the French favourite duck a l’orange) just combine the seasonings of vinegar, citrus fruit and sugar, but it’s also a common combination in desserts (from lemon meringue to cherry pie, lots of classic desserts combine a sour fruit with lots of cream and sugar) and drinks (orange juice remains one of the world’s most popular soft drinks, and many cocktails like the daiquiri and the caipirinha combine sweet liquors with lime juice).
Bitter tastes are, on their own, almost universally hated. Spinach is a punchline, liver is loathed, crabapple is inedible, and the time I mistakenly brought a bottle of tonic water for a game of five-a-side was maybe the worst sporting experience of my life. They almost always need to be combined with another taste group to make them palatable. Salt reliably filters bitter tastes out (one reason it was so valued in Roman times), which is part of why spinach and sprouts taste much better with salt or a bit of butter.** Sweet gin goes well with both sloes and tonic water, a splash of sour lemon makes black tea more drinkable, and kidneys become delicious when combined with umami gravy and meat in a steak-and-kidney pie.
Here’s every possible combo, and a few sauces, dishes or meals that contain each (some of these probably have minor extra taste elements I’m missing, such as pinches of salt or faint sour notes):
Sweet and salty: salted caramel (Sas + Sws), maple bacon (Sws + Sam)
Sweet and sour: lemon meringue (Sws + Swf), KiBa cherry-banana (Swb + Sob), apricot yoghurt (Swf + Sod)
Sweet and bitter: gin and tonic (Swd + Bib), cheddar cheese and apple (Swf + Bid), builders’ tea (Sws + Bid)
Sweet and umami: tomato ketchup (Sws + Umv), fruit and nut chocolate (Swf + Umf), honey-roasted pork (Sws + Umm)
Salty and sour: Fish and chips with vinegar or lemon juice (Sam + Sos)
Salty and bitter: Boiled spinach (Biv + Sas), liver and mash (Bim + Sas)
Salty and umami: Pigs in blankets (Sam + Umm), salted nuts (Sas + Umv), Marmite (Sas + Ums)
Sour and bitter: Dark chocolate with orange (Biv + Sof), Handkäse (Sos + Sod + Biv) – this isn’t a common combination, since it’s the two unpleasant flavours
Sour and umami: Sauerbraten (Sos + Umm), lemon chicken (Sof + Umm), stroganoff (Sod + Umm)
Bitter and umami: Steak and kidney (Bim + Umm), cheese and pickle (Bid + Umf)
Sweet, salty and sour: Coleslaw (Swv + Sas + Sos), wine and cheese (Swf + Sad + Sob), tequila (Swb + Sas + Sof)
Sweet, salty and bitter: Salmiak (Sas + Sws + Biv (+ liqourice flavour))
Sweet, salty and umami: Pulled pork (Sws + Sas + Umm), teriyaki (Sws + Sas + Ums)
Sweet, sour and bitter: Liver and pineapple (Bim + Swf + Sof)
Sweet, sour and umami: Duck in orange (Sws + Sof + Umm)
Sweet, bitter and umami: Matcha latte (Swd + Bid + Umd)
Salty, sour and bitter: Kimchi (Sas + Sos + Biv)
Salty, sour and umami: Gammon with pineapple (Sof + Sam + Umm), sushi rolls (Sav + Sos + Ums)
Salty, bitter and umami: Smoky bacon (Sam + Bis + Umm)
Sour, bitter and umami: Dhansak (Sos + Bis + Umm)
Salty, sour, bitter and umami: Schupfnudel with bacon, sauerkraut and caraway (Sam + Sov + Biv + Umm)
Sweet, salty, sour and bitter: Indian pickles (Sws + Sas+ Sof + Bis)
Sweet, sour, bitter and umami: Duck with Hoisin sauce (Sws + Sof + Bis + Umm)
Sweet, salty, bitter and umami: Chicken and pesto pasta (Sws + Sas + Biv + Umm), Bloody Mary cocktail (Sas + Swd + Bid + Umd)
Sweet, salty, sour and umami: A classic cheeseburger with gherkins, tomatoes and ketchup (Sas + Sav + Sad + Sov + Umv + Umm)
And is there a meal that includes all the tastes at once? You might well eat it every year: the Christmas dinner. Sweet carrots, salty pigs in blankets, sour cranberry sauce, bitter brussels sprouts and umami turkey. No wonder it’s a treat.
* By the way, it’s not true that there are specific parts of the tongue for specific flavours – your taste buds are spread fairly evenly.
** The oils in dairy also help trap some of the aroma, which reduces the unpleasant sulphurous note of many greens.