Category Archives: Science

Jellyfish Of The Week

Does a jellyfish hold the key to immortality? This is intriguing prospect revealed by some research carried out by a team from the university of Oviedo in Spain and reported in the ever-popular Proceedings of the National Academy of Sciences.

Turritopsis dohrnii, a small type of jellyfish no bigger than a finger nail and dubbed the Immortal Jellyfish, starts off life like any other jellyfish, a free-floating larva. It attaches itself to a hard surface and matures into a plant-like polyp. From there several young jellyfish bud off to become medusae or adults.

When it is stressed or damaged, an adult Immortal will, instead of dying, absorb its own tentacles and becomes a blob that settles on the sea floor. Over the next day and a half, the blob becomes a new polyp which then produces more medusae. However, it does not prevent the jellyfish from dying if it is gobbled up by a predator.

Scientists have now identified the DNA part that allows the jellyfish to change from adulthood to a juvenile state at will and, intriguingly, it is similar to that of humans, holding out the intriguing prospect that one day we too could reverse the effects of ageing.

Sometimes ignorance is bliss, methinks.

Formula Of The Week (2)

Having a child in the back of the car can be trying at the best of times, especially when they decide to throw a tantrum. Fortunately, help is at hand to help parents predict when and how to mitigate a fretful child.

According to research carried out by Dr James Hind of Nottingham Trent University, the danger point for a tantrum is seventy minutes into the journey. Providing the child with some form of entertainment (E) for, say half an hour, will delay the tantrum by fifteen minutes and a further fifteen minutes can be bought by providing them with food (F). However, having other youngsters in the car (S) reduces the tantrum-free window by ten minutes.

For the mathematically inclined, he has encapsulated it all into a nifty formula, T = 70 + 0.5E + 15F – 10S, which might be worth pinning to the dashboard. Otherwise, it is worth remembering that the tantrum-free duration of your journey is about as long as you get before having to recharge your electric car.

He also informs us that the average child will first pose the query “are we there yet?” 32 minutes into a journey and will ask the very pertinent question four times per journey.

What would we do without academics?

How Coffee Is Decaffeinated

Doctor Poison might have risen to Goethe’s challenge and discovered caffeine, but the solution to the playwright’s sleep problem was almost a century away and was discovered by accident. Caffeine, a white, bitter-tasting powder in its pure state, is soluble and can be extracted by waterlogging a green, unroasted coffee bean. When German coffee merchant, Ludwig Roselius, took delivery of a shipment of coffee beans in 1903 that had been soaked, he was loathe to throw it away. Instead, after processing some of the beans, he found that the drink tasted and smelt like coffee, just minus the caffeine which the seawater had washed out.

Replacing seawater with benzene, a chemical that, at the time, was used in paint strippers and aftershave, Roselius developed a process for decaffeinating coffee beans which enabled his company, Kafee HAG, to become the first, in 1905, to offer instant decaf coffee on a commercialised basis. Benzene, though, is a known carcinogen and nowadays coffee merchants, who use a chemical-based method to extract caffeine, deploy either methylene chloride, itself toxic if humans are exposed to high quantities, or ethyl acetate.

The green coffee beans are either soaked in hot water and then washed in a chemical solution (the indirect-solvent process) or steamed for about thirty minutes, then washed in the chemical solvent before being steamed again to remove any solvent traces (the direct-solvent process). Purists claim that exposing the beans to hot water, either directly or as steam, damages their natural oils and flavours before the start of the extraction process.

More recently two non-solvent-based methods for extracting caffeine have been developed, the earliest of which to be used commercially, the Sparkling Water method, was also discovered by accident. In 1967 Kurt Zosel, a chemist at the Max Planck Institute for Coal Research in the Ruhr, was working with carbon dioxide and discovered that when the gas is heated and put under pressure, it can be used for separating different chemical substances.

The beans are gently moistened which causes them to expand and widen their pores, giving the more mobile caffeine molecules more room in which to move. They are then washed over with a natural carbon dioxide solution which eases out the caffeine, a process which produce little waste, is completely chemical-free, and does not damage the flavour of the coffee.

Alternatively, the Swiss Water Process, developed in Switzerland in 1933 but not used commercially until 1979 by Coffex S A, uses a heated proprietary Green Coffee Extract (GCE) which contains all the water-soluble compounds found in coffee, except caffeine. The green beans are soaked in it, causing them to swell, expelling the caffeine molecules into the GCE while retaining the more volatile taste and smell compounds. This process can take between eight to ten hours before all the caffeine is removed. While the GCE can be reused for the next batch, critics point out that by doing so the unique qualities of a particular batch of beans can be compromised.

Decaf coffee beans look different from their caffeinated confrères, shinier and darker in colour, a consequence, Andy Cross of Two Chimps Coffee[1] explains, of their drying process, during which, while heated, they rub against and polish each other, creating their characteristic sheen. However, the colour adds to the roaster’s difficulty in judging when they are ready as does their reduced bound water content which accelerates the speed at which they roast. Nonetheless, if decaffeinated well and in the hands of a skilled roaster, decaf coffee will taste just as delicious as regular coffee.   I wonder what Goethe and Doctor Poison would have made of it all.


Goethe, Dr Poison, And Decaf Coffee

Until recently those eschewing alcohol, meat or gluten had a pretty thin time of it, the options available limited and distinctly ersatz in quality and calibre. Now, though, the market for no-lo (no or low alcohol) drinks and free-from (meat, gluten, and wheat) foodstuffs is one of the hottest in the UK’s food and beverage sector as manufacturers recognise that consumers looking for alternatives demand the same quality and choice as offered by more traditional products. A case of the sector waking up and smelling the coffee, you might say, and it could quite easily be decaf(feinated).

Unsurprisingly, decaf is also riding a high, with as many as one in five regular coffee drinkers opting for it, according to Mintel, often as a way of limiting their caffeine intake. Caffeine is fine in moderation, around three to four mugs is most people’s limit, but for those wanting to continue to enjoy coffee’s taste and flavour without the buzz, decaf is the obvious choice. Not that it is entirely free of caffeine; 99.9% must be removed to be classified as decaf in the EU and UK, while the bar is set lower in the US, at 97%.

Most specialist coffee providers now offer a bewildering variety of strengths, aromas, and flavours, with a decaf to suit most coffee drinkers. This is made possible by the way it is produced, by isolating and flushing caffeine from the bean before roasting, as there is no natural caffeine-free bean. This means, as Andy Cross, head roaster of Oakham-based Two Chimps Coffee[1], points out, any bean that is used to make caffeinated coffee can be used to produce decaf and the better the bean, the better the quality of the decaf.

Coffee had made its way from the Near East to Europe by the start of the 17th century, but was met with suspicion, condemned as “the bitter invention of Satan” and banned by the priests of Venice in 1615. It was only when Pope Clement VIII had given the papal thumbs-up after drinking a cup and pronouncing it satisfying that the beverage was taken up with gusto. In Protestant England, by the mid 17th century, there were over three hundred coffee houses in London alone, known as “penny universities” where for the cost of a cup patrons could read the latest journals, engage in lively debate, and transact business with those of a like mind.

So stimulating and energising did regular drinkers find coffee that it began to replace the regular breakfast beverages of the time, wine and beer. Getting a natural high in the morning is all well and good but at night time it can disturb sleep patterns as the German poet and playwright, Johann Wolfgang von Goethe, discovered. A heavy coffee drinker, he was intrigued to discover what was in it that prevented him from getting a good night’s sleep. Who better to help him than the German chemist, Friedlib Ferdinand Runge, whose penchant for dabbling with deadly substances had earned him the sobriquet of “Doktor Gift” (Doctor Poison).

In 1819, after seeing his demonstration of the effect of atropine, a chemical extracted from deadly nightshade, on a cat’s pupils – it dilated them – Goethe showed his appreciation of the scientist’s skills, as Runge described later in Hauswirtschaftlichen Briefen (1866), by handing him “a carton of coffee beans, which a Greek had sent him as a delicacy. “You can also use these in your investigations”, said Goethe. He was right; for soon thereafter I discovered therein caffeine”.

Watch out for a second cup next week.


Mastication Advice Of The Week

Ever since I was a small child, I had it drummed into me that I should eat with my mouth closed and, indeed, there is nothing more off-putting at the dining table than seeing someone move a bolus around their mouth. However, according to a team of researchers at Oxford University led by Charles Spence, in being sensitive to the sensibilities of others we have been depriving ourselves of some of the pleasures to be derived from our meal.  

Chewing with your mouth open, he claims, allows the volatile organic compounds that create aromas and contribute to the taste of the food to reach the back of the nose which stimulates cells responsible for our sense of smell. An enhanced flavour profile adds to our enjoyment of our food as does improving its sound profile. The satisfying crunch of an apple can be enhanced by eating with our mouths open and attacking food with our hands also allows us to appreciate the tactile qualities of foods and to heighten our anticipation of what they will sound and taste like, Spence claims.

There may be something in it, but, as far as I am concerned, it is advice to be followed when dining solo. I wonder just how many dinner invitations Spence has lost since the report came out.