How to create flavour: Part 1

A guest post by Mel Barrett

Mel Barrett writes a regular cookery column for the Wholesome Food Association. Mel is a former management consultant who, since leaving the corporate world, has worked with butchers, bakers and canapé-makers (and many others too!) who share her passion for food produced with integrity. She has authored/co-authored publications for Sustain (the alliance for better food and farming) on bread and London’s food economy, and is currently developing a new kind of cookery course. She has two young daughters. To see Mel’s growing collection of cookery columns, click here.

This special column is the first in a three-part series on flavour.

Our nation, arguably a global leader in many arenas, has, in recent times, lagged way behind on the world stage when it comes to food. “One cannot trust people whose cuisine is so bad”, bantered the former French president, Jacques Chirac, back in 2005. The remark was made in jest, but underlying it is a national stereotype which is proving difficult to shake off, for all the progress being made by a new wave of food heroes. You know you’re in trouble when the boss of a global fast food chain denounces your country’s food as “terrible”, as Bernado Hees, the Burger King chief, did just a few months ago.

Where did it all go wrong? The answer might lie partially in the fact that, despite having a number of fine dishes to be proud of, we have never managed to adopt a unifying set of hallmarks in our cooking, and therefore have no recognisable national style. Furthermore, we have wholeheartedly adopted the cooking of other countries, but, generally speaking, done this badly. Elizabeth David’s remark that “We do seem to be possessed of an unhappy capacity to absorb the worst aspects of any given cooking tradition while remaining deliberately blind to the true nature of the dishes we make our own” still rings true. Why have we been so bad at mastering the art of other people’s cooking, and striking out in confidence with our own? Inferior produce, some would say, blaming a uniquely British combination of factors, including mass industrialisation, long years of war-time rationing and supermarket dominance. But I think a major cause is that, somewhere along the line, we lost our ability to flavour food.

What is flavour?

We perceive flavour when certain types of molecules in our food interact with special cells in our mouth and nose, triggering positive and negative associations (some pre-programmed, some learned) in our brain. Inside the mouth, up to ten thousand taste buds are focused on capturing a narrow collection of taste molecules, those which provide five very defined taste sensations: saltiness, sweetness, sourness, bitterness and also a ‘savoury deliciousness’, known as ‘umami’. In addition, there are receptors in the mouth which detect astringency (the drying sensation caused by tannins), piquancy (the hotness of chilli and peppercorns) and pungency (the irritation triggered by horseradish, mustard and raw garlic, also sensed in the nose).

Inside the nose, five to ten million smell-sensing cells have a much broader remit, receiving thousands of small, airborne aroma molecules which float up into the nasal passage from the food being chewed in our mouth (or in through the nostrils). It is these odorant molecules which account for most (some estimate up to 80%) of what we perceive as flavour (to test this, try holding your nose whilst tasting certain foods).

Getting taste and aroma molecules into our food, then, is the key to flavour. From a glance around the world at many of the delicious styles of regional and national cooking we can learn three things: the importance of taste, the magic of aroma and the art of balance.

The importance of taste

Taste molecules, which only need to be added in very small quantities to be effective, do a very important job:

• Saltiness (from table salt, along with a range of other products to which salt has been added, for example, cured meats and brined vegetables) enhances flavour
• Sourness (from acids, found in vinegar, plants and sour milk products) is said to stimulate the appetite, and has a sharpening and brightening effect
• Sweetness (from a range of table sugars, sweeteners and foods which contain high levels of naturally occurring sugars and sugar-releasing starch, for example, onions and carrots) softens and mellows savoury dishes, counteracts bitterness and sharpness and generally makes most foods more appealing
• Bitterness (from alkaloids, strong chemical compounds found in plants) balances sweetness
• Umami (from glutamate, found in meat, fish and vegetables; inosinate, found in meat and fish; and guanylate, found in mushrooms) heightens flavours, lengthens their duration in the mouth and creates a delicious, mouth-watering savoury sensation.

In other words, taste molecules make our food taste good, and keep us coming back for more. Many cultures in history have understood the role taste molecules play. “There is no better food than salted vegetables” we read on ancient Egyptian papyrus, whilst Pliny said of acid “No other sauce serves so well to season food or to heighten flavour”. The Egyptians enjoyed a sauce known as oxalme, made from brine mixed with vinegar; this was later used by the Romans, along with their ubiquitous umami-rich fermented fish sauces garum and liquamen, relatives of the fish sauces and pastes still used in Asia today (nam pla from Thailand; nuoc mam from Vietnam; terasi from Indonesia), and a very distant cousin of our own Worcestershire sauce.

Food manufacturers know this too: processed food, in particular crisps, condiments and other products designed to flavour food, are often jammed with lab-produced taste molecules. Synthesised sugars (e.g. glucose, dextrose, fructose and maltodextrin), acids (e.g. acetic acid or ‘spirit vinegar’) and umami (‘hydrolysed protein’, yeast extract and monosodium glutamate) are all taste molecules added to heighten flavour. These products, cheap to buy for the manufacturers, are often added in high quantities to compensate for low quality raw materials (and to the detriment of our health). Taste doesn’t need to come out of a packet though – it can be created very easily by adding foods to the dish which contain high levels of naturally occurring taste molecules (more about these in the next column).

The magic of aroma

Whilst taste molecules set the tone of a dish, and make us want to eat more, aroma molecules add interest, variety and a further layer of deliciousness. The complex molecules of which proteins and carbohydrates mainly consist are too large to vapourise (hence very fresh, raw meat and uncooked flour have little aroma); only small molecules, which evaporate when exposed to the heat of our mouths, are able to float up into our olfactory system.

Plants are our biggest source of these, with the ones we tend to use for flavouring purposes typically containing over 100 different aroma compounds, usually concentrated in the leaves and stalks (we tend to refer to these parts as herbs), as well as the berries and seeds (these, in their dried form, we refer to as spices); some plants also offer up flavour in their bulbs (members of the allium family, e.g. onions and garlic), flowers (cloves are dried buds; saffron the stigma of croci), roots (licorice) and underground stems (ginger and turmeric). The sum of all the aroma compounds extractable from a plant is known as its essential oil, its ‘essence’, and it is this we try and capture when flavouring our food. Often dangerous to humans in large quantities, the small amounts used in the kitchen bring extraordinary life and vitality to our dishes.

Some alcohols are also good sources of small aroma molecules. Wine contains over 200 aroma compounds, which explains its popularity as a cooking ingredient (as well as the varied and complex vocabulary used to describe its aromas, or ‘bouquet’).

Finally, in certain foods, new small aroma molecules can be created on the surface by heating. When foods which contain both proteins and sugars – including meat, fish, potatoes, onions and wheat-based products such as bread and cakes – are heated at high temperatures (from 154°C), some very complex reactions take place, resulting in wonderful ‘roasted’ flavours . These are known as Maillard reactions, and are the reason why recipes instruct the cook to brown or ‘seal’ meat before adding it to the pot.

The art of balance

Getting taste and aroma molecules into food is relatively simple (more on this in the next column). The challenge lies in deciding which combinations to use. Firstly, tastes must be balanced. Food excites the most when all the sensors in the mouth are activated, so a good rule of thumb is to include some salt, some acid, at least one umami-rich ingredient and a little sweetness in every dish. Piquancy or pungency can be added for further sensory stimulation. And for extra deliciousness, several sources of umami should be combined (according to the Umami Information Centre, the use of different types in one dish has a synergistic effect, greatly magnifying the sensation). Secondly, there must be a balanced used of aroma molecules. Too much of one herb or spice can overpower; strong and pungent flavours should be used carefully; flavour compounds must work together.

Other cultures have mastered the art of balance. Many of the hundreds of different cuisines throughout the world are built on a solid framework of tastes. Typically, a mix of vegetables, providing glutamate, sweetness and sometimes pungency or heat, is used to form the base of many dishes. In France, the base, known as mirepoix, consists of onions, carrots and celery (the same as is used in Italy). In Spain, the mix is called sofrito, and contains garlic, onion and tomatoes. In Chinese cuisine it is spring onions, ginger and garlic. To such vegetable bases, various locally distinctive acids, salted products and umami-rich ingredients are added, for example, rice wine vinegar and fish sauce in China; lemon juice, pancetta and parmesan in Italy. Then, a harmonious blend of herbs and or spices, often sourced from the region, is layered throughout the dish.

And the British? It is probably true to say that the use of aroma molecules in our cooking – herbs, spices, wine – does not come naturally to us, with one important exception: the use of Maillard reactions. We love our roasted and browned food, for example roast meat and potatoes; Yorkshire pudding and cottage pie. We do understand the importance of taste (Elizabeth David informs us that for several centuries following the Stuart period the English were using grated parmesan as a seasoning, and 18^th century cookbooks are packed with recipes for pickled vegetables and acid-containing salad dressings), but somewhere along the line we stopped using products which are rich in naturally occurring taste molecules, turning instead to processed ones.

Perhaps we need to look harder for our own sources of natural acids, but they are there: gooseberries, blackcurrants, crab apples, cider vinegar and sorrel, to name but a few. So too are sources of saltiness (bacons and hams), along with aroma molecules in abundance, for example mint, cider and all manner of ‘heritage’ fruit and vegetable varieties which thrive in our soils. English food ‘terrible’? It really doesn’t need to be.

This column content (excluding images) © Mel Barrett 2011.

All images from Flickr, used under Creative Commons Attribution License. Click image to enlarge.