Food shopping is such a complicated business when you want to ensure each item is infused with political correctness.

Is it, for instance, fair trade? Does it own food miles?

Has it been genetically or artificially challenged?

I'm sure Stone Age man didn't have to worry whether his woolly mammoth was free-range or not. Whenever he managed to catch one, he could eat it without reservation.

These days, we may be surrounded by food but we know much of its nutritional value is questionable or ethically unacceptable.

That's why we may be getting a little fussy.

Most of us are bright enough to know that presentation or clever marketing of a product doesn't necessarily mean quality. But how does one tell what is a quality product?

Stone Age man depended very much on his sense of taste to tell him which plants were poisonous. His tastebuds were essential to his very survival.

If the plant was bitter, it was likely to be poisonous so he didn't eat it.

Taste receptors for bitterness are well developed in humans - we may have as many as 20 - but, surprisingly, we have only two sweet receptors.

The reason is, most sweet-tasting plants are nutritious, few things in nature being both sweet and poisonous.

Our natural dislike of bitter-tasting things is a useful device to stop us from swallowing toxic substances.

However, this may be about to change. Linguagen Corporation, a biotechnology company in New Jersey in the US, has discovered ways of tricking our tastebuds with compounds that block the perception of bitter substances.

The company's food scientists say their so-called "bitter blockers" are useful compounds which improve the flavour of prepared foods without the need to add large amounts of salt or sugar.

Applications could include grapefruit juice without added sugar or Diet Coke without artificial sweeteners.

Needless to say, the food industry is showing great interest in the new era of taste technology. There's also tremendous commercial benefit for the pharmaceutical industry, as many medicines taste awful.

What a great incentive for us all to drink more Diet Coke and take more medicine.

Call me a killjoy if you will but I'm not convinced the exploitation of our tastebuds is such a good idea. Our sense of taste is already far less reliable than it used to be thanks to added (and often hidden) doses of sugar, salt and artificial flavourings in convenience food.

If humans are denied the ability to experience any trace of bitterness, will they be able to appreciate the sweetness?

More importantly, will we able to tell if food is mouldy or toxic?

There's also tremendous potential for defrauding the customer with low-quality ingredients. Who is going to notice if cheaper, bitter coffee beans are used in coffee when we can't taste the difference?

Food choices have become complicated enough already and we need to take more responsibility for what we eat rather than less.

Altering taste perceptions is just a new form of "food spin" which distorts our ability to judge the health effects of our food choices.

So, thanks very much, but I'd rather rely on my own good taste.

Martina is a qualified nutritional therapist at the Crescent Clinic of Complementary Medicine, 37 Vernon Terrace, Brighton. Tel: 01273 202221 or email: martina@thehealthbank.co.uk