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THE LAST WORD

Taste revelationThe first time I tried an olive I disliked it intensely. The same thing happened when I first drank wine. Now I love both. What happens to our sense of taste to allow us to start liking such foodstuffs? And, just as intriguingly, what makes us persevere with them at first?

n As we age, we progressively lose parts of our senses of taste and smell. The first parts to go are those that make us dislike certain foods. Much later in life, we begin to lose the parts that allow us to enjoy our favourite foods. In between is the golden age of the gourmet – enjoy it while you can…Alan Chattaway Surrey, British Columbia, Canada

n Our genetically acquired senses of taste and smell encourage certain preferences, such as that for sweetness, or avoidances, such as those for bitterness or faecal tastes, but we are by nature nonspecialist, socialising omnivores. If we are

neither to starve nor poison ourselves, we must learn which foods are good for us and which are not. A good rule is: “What you or your friends don’t know or don’t like is nasty.” This rule is, however, subject to circumstances such as famine and social pressures such as hospitality.

The rule is also subject to experience, for example: “That nasty-smelling cabbage left me feeling nice and full; now it doesn’t smell so bad. But having vomited kidneys while in the middle of a fever, I can’t even stand their smell!”

Alien foods tend to repel us at first, especially if our gastronomical experience has been narrow; a friend of mine offered an apple to an Ovambo girl in northern Namibia – she took one bite and promptly spat it out. She was used to wild fruit that, to Western tastes, are insipid, astringent or generally vile. Perhaps some ancestor of ours was starving and so decided to try olives and then, having learned to prepare them and like them, passed on the liking. Now enthusiasts perennially offer us olives in various dishes, and gradually our system adapts.Jon RichfieldSomerset West, South Africa

Sock it to meI have four or five pairs of boots, all pretty similar in style. However, after walking in a particular pair for about half a kilometre, my socks have worked their way down to the toes. I have to keep stopping to pull them up. What’s up with these boots?

n The process of walking involves friction between a living surface – the skin – and a covering surface – the shoe, boot or slipper. Between the two is a flexible thin layer of knitted or woven wool – the sock.

The shape of the foot and its relation to the shape of the shoe will determine the degree of friction between the two and the extent to which the sock moves in relation to one or the other. Mode of walking is another factor.

High-friction living surfaces – sweaty feet, for example – will

tend to adhere to the flexible sock layer and drag it across the inner surface of the shoe. This produces a holey sock. But more usually the sock slides freely between the two surfaces and returns to its position after each step.

When the foot or shoe surfaces or the socks carry a texture – a nap or grain that “leans” in a given direction, the friction will be greater in one direction, so there is a kind of peristalsis that pulls the sock along between the surfaces. In this case we might describe the boot as “sockivorous”.

A tendency for the sock to pull upwards is defeated by the toe end of the sock unless the holes are extremely large at that end. More usually, the motion is detected downwards producing a discomfort around the heel and then a feeling of compressed wool around the toes. Ill-fitting shoes that leave space around the foot produce the most sockivorosity. Snugger shoes are not so hungry.Don LeechExmouth, Devon, UK

n When one walks, there is considerable relative motion between the foot, the sock and the boot. I reckon that the socks work their way down to the toes because the inner surface of one of the pairs of boots is subtly different from the other pairs and this causes a “micro-racheting” effect similar to that which causes a mat, when walked on, to slowly work its way across the underlying carpet.

As an extension to this idea, I find that having a very smooth-surfaced inner-sole to the boot is an excellent way of reducing the likelihood of blisters.

The smooth inner-sole allows an easy sliding movement between the outer surface of the sock and the inner-sole of the boot, with the result that the inner surface of the sock and the skin of the foot stay pretty much together, minimising the rubbing between skin and sock – a key cause of blistering.Richard BellCadeleigh, Devon, UK

This week’s questionPained reSPonSeI recently found a packet of ibuprofen that had expired. What happens to drugs such as these, and paracetamol, after expiry? Are they less efficacious or even harmful? They looked just fine although I thought it best not to take them.Paul InsteadGrimsby, Lincolnshire, UK

“alien foods tend to repel us at first, especially if our gastronomical experience has been narrow”

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“High-friction live surfaces, such as sweaty feet, will tend to adhere to the flexible sock layer”

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