The evolution of cutlery materials

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Update time : 2021-11-30 17:48:37

For centuries,stainless steel has completely changed the bad taste diet.

It took thousands of years to find cheap metal cutlery that has no adverse reactions to food.
The stone age equivalent of Jamie Oliver and Mary Berry were handicapped by the lack of cooking utensils, and also ate with their hands. When the copper age arrived, it delivered better tools for cooking, but not for eating. Copper is poor material for making spoons because it has a very strong taste. The bronze age brought with it stronger metals but they did not taste any better, so eating with the hands continued in most parts of the world except in east Asia. There, they cracked the problem by developing chopsticks. That the rest of the world didn’t adopt this remarkable invention is odd, especially when you consider that metal cutlery that didn’t have a taste, took more than another 6,000 years to develop.

The first breakthrough in this quest was the discovery that gold utensils, as well as looking fabulous, are inert and so do not interfere with the flavour of food or drink. They didn’t know it at the time, but this is associated with the high electrode potential of gold, which means it doesn’t chemically react with very much. Since it does not react with the food, drink, or the indeed the mouth, it doesn’t produce new compounds and so doesn’t have much of a taste. Job done, you might think, except that gold is too rare and expensive to be a practical choice for anyone except kings and queens.

Silver is quite inert, but has a lower electrode potential than gold and so does react with some foods and indeed the mouth, producing a mild metallic taste. It is rare and expensive too and so was used only by the rich. More plentiful metals like copper, bronze and iron have electrode potentials that are lower than silver, react with quite a lot of food, and taste foul. Thus for most of recorded history, those not using chopsticks either ate with their hands, with cutlery made from metals that taste quite strong, or from other nice-tasting materials such as wood.

Then in 1743 the cutlers of Sheffield found a way to cover a layer of silver over copper, and so use much less silver to produce a whole canteen of cutlery. Called silver plate, this allowed the growing merchant class in Britain and elsewhere to eat with only the min. of oral displeasure. Then in 1840 with the discovery of electricity, electroplating was born. This made silver-plated cutlery even more affordable, and so the middle class could have silver, and eat with dignity.

Nevertheless the problem remained: silver still had a distinct taste. Napoleon III had the money to try using aluminum which, although mostly unreactive because of a protective oxide layer, discolors easily. Plastic spoons came into use in the 20th century but, despite their chemical inertness, they couldn’t compete with silver. This is partly because the shine and glitter of cutlery are an important part of the experience of eating. A polished spoon speaks of cleanliness in a way that no matte plastic surface can. Besides, to be born “with a silver spoon in your mouth” was a status symbol, a sign of being part of a prosperous family.

It was a metallurgist called Harry Brearley who made the breakthrough, and in doing so revolutionized every cutlery drawer in the world. In 1913 he had the job of making better steel alloys for gun barrels. He was working in one of Sheffield’s metallurgy labs and trying different alloying elements to improve the hardness of steel. If they didn’t look promising when tested he chucked them in the corner. One day he walked through the lab and saw a bright glimmer in the pile of rusting rejected specimens. He fished out this specimen and realized its significance: he was holding the first piece of stainless steel the world had ever known.

Well, not quite: materials scientists in France, Germany and the US had, unbeknown to him, already discovered that adding chromium to steel changed the electrode potential of its surface by creating a stable and transparent oxide layer, making it resistant to rusting. What made Brearley special was that he discovered it in a city renowned for its cutlery, and so he had the urge to put it in his mouth and see if it tasted of anything. The 6,000-year quest for an affordable tasteless metal was over.

Of course we take it for granted now. It has become the metal with which we are the most intimately acquainted; after all, we put it in our mouth almost every day. The average kitchen is full of stainless steel cutlery, pots and pans, not to mention the kitchen sink. Ultimately it has been a very democratic invention, giving everyone, however poor, a culinary experience as exceptional as using gold.

So it is really odd then, that on special occasions, people still get out their silver cutlery. The material can’t compete with stainless steel for taste, and so would be better recycled to make solar cells or jewellery. We are the generation born with stainless steel spoons in our mouths, and we should be very proud of that.