We haven’t been using it much recently, though, owing to the exciting new website called The Reaction.

It’s been up a few months and is a home for all things entertaining and chemical. There are plenty of news stories about the chemistry of everyday life, chemistry in the media, interesting anniversaries or things we just wanted to write about.

It’s got a great and expanding library of the best chemistry videos on the net. You can look at photos and videos of past public events at The Chemistry Centre in London. And there’s info about why the 21st century science of chemistry really matters to the future of our planet.

It allows us to write about things that have previously graced this blog, from chemically-perfect recipes for Yorkshire puddings and gravy to ridiculous packaging claims of “chemical-free” products.

The DISQUS comments make it easier than ever to discuss the stories using your existing Twitter, Facebook or other accounts, and to share the stories with your various social networks.

So head on over! This blog is staying put because there’s loads of great content, but it won’t be updated from now on. Thanks for reading.

www.thereaction.net

She was a selfless and dedicated scientist who among her many accolades in 60 years of research co-wrote the pioneering text The Composition of Foods (still the leading resource in food science), was responsible for the first compulsory food additive for health (calcium in bread) and preserved the health of the country in difficult times, overseeing the rationing of food in Britain during and after World War II.

In December last year the Royal Society of Chemistry awarded Chemical Landmark status to the Elsie Widdowson laboratory at MRC Human Nutrition Research in Cambridge. I attended the plaque unveiling, which followed a lovely talk by the Director of the facility Dr Ann Prentice, and had the chance to chat with people who knew and worked with Dr Widdowson (“oh please, call her Elsie”, I was berated). They all spoke of her passion for science, her warmth and her empathy.

Elsie was delighted to have the building named after her, and cut the first sod in 1999, but sadly passed away at the age of 93 before its completion in 2001. Her long life may have been down in part to her nutritional expertise, but is astounding considering her experimental prodcedures: she would always try experiments on herself before asking anyone else.

She said in her biography: “We did not believe that we should use human subjects in experiments that involved any pain hardship or danger, unless we had made the same experiments on ourselves.”

Elsie gained a degree in chemistry and PhD from Imperial College London in 1928, studying the carbohydrate content of apples for her thesis. When observing large-scale cooking in a hospital kitchen, she met a doctor studying cooked meat named Robert McCance. Their common interests led to an MRC research grant for both to work together, the first venture of a 60-year scientific partnership.

The pair shortly realised the need for a single authoritative source of composition data for food, so set about writing one in 1934. The first edition of  “The Composition of Foods” was published in 1940 and is more commonly now known simply as “McCance & Widdowson”. Now in its sixth edition, the book is published by the RSC and endorsed by the Food Standards Agency.

As war began in Europe in 1939, McCance and Widdowson studied the effects of rationing food, with a view to determining the bare essentials for a healthy population. As ever they began with themselves, living on a meagre diet for three months then undertaking a 36-mile walk through the Lake District in 12 hours! The two deduced that calcium supplements (delivered in bread) would be important for the wartime dairy-restricted diet, and consequently they were made responsible by the Government for national wartime and post-war rationing. It’s often said that under their rationing Britain had the healthiest diet it has ever had.

After the war they worked in Germany for a few years, after which they were both elected Fellows of the Royal Society. Moving back to England they continued their studies on malnutrition. Elsie was appointed Head of Infant Nutrition Research at the Dunn Nutrition Laboratory, and after a brief spell of retirement moved to Addenbrooke’s Hospital in Cambridge in the Department of Investigative Medicine.

Elsie was made President of the Nutrition Society, Neonate Society and the British Nutrition Foundation, awarded many other medals and awards, appointed CBE in 1977 and in 1993 made a Companion of Honour, a fitting recognition of a lifetime dedicated to science. The UK owes Elsie its continued health after devastating war, and her rigour and fairness of scientific method should be an aspiration of all scientists.

[I originally wrote this on tumblr, here: jonedwards.tumblr...]

Recently, after the publication of “Dementia 2010″, I was invited by the Royal Society of Chemistry to chair one of its public lectures, by Professor Chris Dobson, who is master of St. John’s college and from the department of chemistry. He lectured on some of the extraordinary work done by him and his team of young graduates on the disease mechanism behind dementia and the role of proteins in the body. It is a potential key not only to unlocking our understanding of the disease, but to identifying treatments for dementia that arrest its progression and might even cure it. The team also established a link to other neurological conditions in our understanding of dementia. That research is being done in this country. We need more such research and the ambition to fund not just a cure, but the discoveries necessary to build bridges to it. [taken from Hansard, 16 March 2010]

So in Parliament, the science community, and the world, the RSC is helping to promote the critical role of the chemical sciences in improving health for all. We’ve been delighted over the past few weeks to work with a phenomenal team of scientists, led by Professor Dobson, and showcase their work in a variety of ways including in Parliamentary debate, interviews, media coverage and a superb lecture at the Chemistry Centre here in London.

The Dobson group at the University of Cambridge conducts world-leading research into Alzheimer’s disease and other ageing diseases. Their 50-strong team from a wide variety of disciplines, from neuroscience through to theoretical physics, takes a whole new approach to neurodegenerative diseases.

As opposed to the standard tactic of targeting a small number of proteins associated with a disease, the Dobson group try to understand how proteins in general clump together to become toxic. This clumping causes many different diseases – Alzheimer’s disease, Parkinson’s disease, even type II diabetes – and the Dobson group is the first to link these to a common biological malfunction, the so-called “misfolding” of proteins.

The number of people with Alzheimer’s disease in the UK will more than double in the next 40 years – this “ticking timebomb”, as Professor Dobson calls it, is a problem the young and middle-aged people of today should be concerned about, as its serious impact will hit them in later lives.

The RSC discovered the Dobson group’s work at the IUPAC congress in Glasgow, hosted by the RSC, in August last year. Professor Dobson gave a brilliant plenary lecture to scientists from around the world, and the significance and visual impact of the group’s work with fruit flies appealed immensely.

Professor Dobson was invited to give a very well-received lecture at the Chemistry Centre in Burlington House, chaired, as mentioned before, by Paul Burstow MP.

We also talked in person to the group about their research and put together a short film (4 minutes) telling the vivid story of their work, its significance, and the threat to full realisation of the research should funding from the government fail to support the high-tech industries essential for the UK’s economic future.

As I cut this video together then the news media had already taken an interest: Cambridge News highlighted it with a news piece and some of the same footage (see it here), and ITV Anglia also went to the lab and reported on the research (see that here).

We hope to continue working with the Dobson group and many other groups around the UK doing world-class research, and continue to demonstrate to everyone that better health comes from better chemistry.

So here’s a double chocolate treat from the RSC, to get you in the mood: a snippet of science info to help you get the full effect from your choccies, then a brief yet fascinating history of chocolate in Central America.

The sixty-second science savour

Chocolate expert Stephen Beckett (who happens to have written an excellent book on the subject) told me that your average piece of chocolate takes about a minute to melt in the mouth. The cocoa butter is liquid at body temperature and this of course provides maximum surface area for the flavour molecules to interact with your tongue and mouth.

So having spent a small fortune on the perfect Valentine’s chocolates, be sure to stop your loved ones from gobbling them down uncontrollably – there’s not a hope they’ll be getting the full effect unless they’re savouring each bite for 60 seconds or more.

With that practical tip out the way, I present with pleasure a brief history of chocolate written by Ian Foster, a British science history buff with near-limitless knowledge and enthusiasm, and friend of the RSC.

—

From Mesoamerica with Love

The tradition of giving chocolate on Valentine’s Day is connected to an ancient practice originating in Mesoamerica, where the early civilisations explored the mystical and magical effects of the plants and animals around them.

Chocolate was originally a drink made from the fruit of the cacao tree which grew wild in the lowland jungles of Central America in the shade of the jungle canopy. The legends of the ancient people tell of a heavenly garden where mankind and the Gods once lived in harmony – until mankind was banished from the garden as a punishment for attempting to become equal to the Gods.

Life on the outside was hard, and the God Quetzalcoatl was fond of mankind, so he brought them the cacao tree from the garden to make their life easier. This tree bore the fruit that was the magical food of the Gods and the secret of their power. Quetzalcoatl stayed with Mankind and taught them the fruit’s uses before returning to the Garden, promising he would return some day. The modern scientific name for cacao as given by Linneaus is Theobroma Cacao, which in Greek translates to “Cacao, Food of the Gods”.

The fruit of the cacao tree is a rugby ball-shaped pod containing 20-40 beans, which are encased by a sweet white flesh something like lychee. The flesh can be sucked from the bean and makes a delicious drink rarely experienced outside of the cacao growing areas. The early Central American people – including the Olmecs, Toltecs and Maya – fermented and dried the beans before roasting them. They sometimes extracted a liquid from the beans during fermentation which was drunk as a wine, and was very intoxicating owing to the ethanol content caused by the fermentation.

After roasting, the beans were ground to a paste and mixed usually with hot water to make an oily liquid. This was poured many times from a height between two containers to create a foaming liquid and consumed by the pleasure-seeking people of the Maya as a luxurious and health-giving drink. It was also an important part of their rituals such as marriage ceremonies, where couples gave each other the chocolate drink in preparation for the wedding night experience.

The drink was a bitter elixir and the makers had no sugar but used honey, vanilla and ground maize to add body and flavour. Vanilla is known to have an aroma reminiscent of breast milk and honey is linked to sex in many cultures along with nectar as the high energy fuel of the hummingbird.

There was no milk in this chocolate and it was a potent and stimulating concoction that Europeans found hard to stomach. It was used for its physical effects which were found to aid in providing strength and vitality as described by the English doctor Henry Stubbe in his book about chocolate, published in 1662 and titled ‘the Indian Nectar’.

“The Indians, as they in all things almost affect a simplicity, so in the making of Chocolata they did not multiply ingredients; and cared rather to preserve their health, then to indulge their palates,” wrote Stubbe.

It is said that prisoners who were awaiting execution were given chocolate to calm them and increase their vitality – before facing the prospect of having their beating heart cut out. A red vegetable dye called achiote was sometimes added, but priests and shaman would also add their own blood to ritual chocolate.

On the arrival in what is now Mexico of the Spanish conquistador Hernan Cortez, he was welcomed warmly by the Aztec emperor Moctezuma, who may have believed this stranger was the incarnation of Quetzalcoatl, who had promised to return. Moctezuma shared his secrets with Cortez, including the chocolate drink, and consumed 50 servings of chocolate from golden goblets before retiring to the pleasures of his harem. Cortez and his men were told that the drink was “effectual to provoke lustful desires towards women”.

Moctezuma sometimes enjoyed chocolate chilled after being poured over snow brought from the high mountains. The cacao beans were valued more highly than gold and Cortez recognised that there was something very special about this bitter drink, which a soldier could use to maintain his strength for days while consuming no other sustenance.

The Aztecs received cacao in tribute from people they had conquered in lowland areas and the use of it was reserved mostly for males of the nobility. Women were responsible for making the chocolate drink and enjoyed it usually when sharing it with a man

Stubbe wrote “for the benefit of the married” that “Let us take it for a certain position that What yields the best Blood, and promotes all naturall expurgations, is the best of Food and Physick. And that Chocolata is such…Thus solid and substantial Butcher’s meat, and the like, are the only lustful sustenance to a good constitution, and strong body injured to vigorous Exercises; for the performances of the bed are not created therein. Ease and soft-lying do but effeminate the body, and they become unable to concoct strong meats: and the Seed becomes worse-digested, and, as I may call it, worse relished for the Gusto of the Womb; the erection is less vigorous, and the spirituascency of the seed little; and the ejaculation too sudden, weak and improportionate to the ardours, and desires, and expectation too of the Female Paramour”.

The title of the popular novel Like Water for Chocolate, by the Mexican writer Laura Esquivel, recalls the ancient phrase describing the sexual passion of a person being as “hot” as water that is necessary for melting chocolate to create the chocolate drink. The 16th century Spanish traveller Hernandez wrote “This potion was not used for sustenance alone, or as a drink invented as an enforcing necessity, but, out of a luxurious designe.”

The 17th century Spanish doctor Antonio Colmenero de Ledesma wrote that chocolate “vehemently incites to Venus”. Chocolate was believed to boost breast milk production in women and generally stimulate the body to produce bodily fluids which Stubbe noted “are to be discharged out of the body by their several passages, one whereof are the spermatick vessels”

Chocolate came to be popularly consumed in Central America and the Caribbean, especially first thing in the morning. It was used as a love potion by women and men who would spike it with all manner of sexual ingredients to encourage the amorous desires of the drinker.

Its magical and spiritual qualities were believed to be the most important aspect of chocolate and farmers would abstain from sex for two weeks before planting. The taste and sensations were often savoured after eating in a period of meditation. Certain rare types of cacao plants were protected and cultivated by highly skilled botanists and reserved for the most special occasions.

So now on Valentine’s Day chocolate is once again used to stimulate desires, packaged in elaborate golden wrapping and presented to someone special as it was in Moctezuma’s time. The key to the aphrodisiac qualities of chocolate is the effect it has on the body in combination with the influence on the pleasure and sensory elements of the mind. But of course it has to be good quality chocolate – a rare thing in the modern world.

—

Bonus: from the wonderful webcomic xkcd.com

Beer has been a vital part of society for almost all of civilised history. 4000 years ago the Sumerians were brewing in honour of their gods; in medieval Europe beer represented something clean to drink when the purity of water was questionable; nowadays it’s used more as a social lubricant. And which discipline of natural philosophy is responsible for this nectar of culture, health and prosperity?

Well of course I wouldn’t be writing about it if it weren’t chemistry. But therein lies the problem – who these days cracks open a can and thinks to themselves “thank goodness for the clever research chemist who invented a vinyl co-polymer/C-enamel coating for tin cans”? But chemists are the ones behind all these advances in canning technologies and the art of zymurgy (“chemistry of brewing and distilling”, dontcha know).

As we put out the call for surviving cans of “Party Seven”, a septa-pintal vessel taken to parties in the 60s and 70s containing (allegedly) decidedly ungourmet beer, I thought I’d look into the chemistry of beer cans – and would you believe it, the beer can’s 75th birthday is later this month. See the bottom of the post for more details on our Party Seven quest.

On 24 January 1935 a revolutionary product from a relatively small brewery hit the shelves in Richmond, Virginia. Krueger Finest Beer came from the Gottfried Krueger Brewing Company in Newark, New Jersey, and was the first beer to be sold in cans. Far enough away from their home turf that rejection of the cans wouldn’t hit their profits, Richmond became the birthplace of a new beer storage phenomenon, as while the other breweries watched from a distance the public literally lapped up the new canned beer.

Canning had of course been around for a while before 1935, but two major problems had hampered progress of canned beer: pressure and corrosion. The welded seams which held cans shut couldn’t stand the pressure required for beer at the time (80lbs/sq in), but more troubling was the drink’s tendency to react with the tinplate of cans at the time.

The pressure problem was solved with better welding techniques, but it took until 1933 for American Can to come up with a process to protect cans from their contents. Vinylite, the polymer also used to make vinyl records, was applied to the inside of the cans and protected them from corrosion. Another year’s research led them to a “dual coat process” involving enamel and Vinylite, which they called “Keglined”, and this was the coating used in Krueger’s groundbreaking first cans of beer.

Krueger's first canned beers: Finest Beer and Cream Ale

So that’s the cans themselves, but what about the beer inside them? Brewing itself is perhaps the earliest successful example of biotechnology, but the bit of chemistry/physics I’d like to focus on is the problem of giving beer a creamy head as it’s poured out of the can. Enter the widget.

After mediocre success with a syringe-kinda-thing known as an initiator, Guinness (of Guinness fame) were keen to bring that draught smoothness to cans. Two revered names in brewing, Tony Carey and Sammy Hildebrand, are on the patent that suggested a “sudden gas discharge from an internal compartment” to inject a bit of life into the beer as it was opened.

The widget in a Guinness can

This was initially from a compartment attached to the can itself, but was a bit tough to manufacture so this was left alone for a while. A few years later the widget, a hollow plastic sphere about an inch across with a little hole in it, was developed.

Guinness hasn’t as much CO₂ dissolved in it as some beers, so when it’s poured from the can (as opposed to from a tap) it seems a bit lifeless. The widget is filled with nitrogen and held in the can while it’s filled with beer, and as the can is sealed off they add a shot of liquid nitrogen. As this evaporates it pressurises the can and further pressurises the nitrogen in the widget.

When the can is opened, the pressure drops and the nitrogen shoots out of the hole in the widget, agitating the beer and bringing the carbon dioxide out of solution – giving you a nice creamy beer. Magic, maybe. Chemistry? Definitely.

There’s two of the many ways that chemistry has improved our enjoyment of the good stuff since the 30s. If you’d like to know or share any more info about the science of beer, let me know in the comments!

And now to the nub of the matter: Party Seven. If you have a can of Party Seven, reasonably well-preserved, please do send us a photo – or if you don’t mind relinquishing it, arrange to send it to us! Contact Brian on emsleyb AT rsc DOT org with your photos or submissions.

We may, of course, take it unto ourselves to put the preservative chemistry to the test with the RSC press office’s vast array of “complex scientific experiments”, developed in the pub. It seems to me that there’s only one way to prove this 75-year-old technology…

Your Party Seven photos

Andy Barkley sent in this photo of his thirsty friends holding with pride a Party Seven. “Sorry, can’t supply a real can, but here’s a photo from a trip to the Isle of Man.  I went there in 1974 with the pictured guys.  We were 6th formers doing our A levels in a very troubled Northern Ireland,” Andy told us.

Andy's friends clearly pleased with their beerhemoth

Neil from Shrewsbury sent this in – it’s a commemorative can from the 1980s in very good nick. See Neil’s comment for more info.

A "Party Seven" commemorative can from the 1980s

This follows the success of last year’s ideal Yorkshire puddings (popovers to our American friends) – and the decree that they cannot be named so unless they rise to four inches or higher. Chemist, author and roast dinner expert John Emsley has issued a new recipe for nutrionally-balanced, chemically-perfect and extremely tasty gravy in the tradional fashion… sort of.

It combines some traditional elements with some chemistry magic – most controversial is the inclusion of soya sauce, normally associated with Eastern cuisine but here included in the quintessential Englishman’s Sunday roast.

Here’s John’s recipe:

Ingredients

The juices from a roast joint of meat, preferably beef
Flour
Vegetable water (cabbage)
Iodised salt
Teaspoon of dark soya sauce.
Pepper
Gravy browning if you prefer a darker gravy.

Method

The joint should be cooked on a bed of halved onions, carrots and celery on to which juices from the meat will slowly trickle. When the meat is cooked, remove it from the roasting tin along with the vegetables. Sprinkle a small amount of plain flour over the meat juices and fat. Stir to form a dough (roux) gradually adding the water in which vegetables have been cooked, preferably cabbage water. Ensure all the meat juices and Marmite-like deposits on the bottom of the roasting dish have dissolved. Then add iodised salt to taste and a teaspoon of dark soya sauce (rather than gravy browning) or a little red wine . Simmer to reduce the volume of liquid to the right consistency, stirring occasionally.

Chemical and nutritional composition of gravy

Protein from the collagen of the meat.
Vitamins, and especially B1, B6, folic acid, riboflavin and nicotinic acid.
Carbohydrate from the flour and gravy browning. Gravy browning is caramelised sugar and can be bought, or it can be made using the recipe in Mrs Beeton’s Book of Household Management published in 1859. This says to heat sugar until it caramelises but does not become too dark.
Minerals such as sodium and iodine.
Monosodium glutamate (MSG) from the soya sauce which brings out the meaty (umami) flavour.

What do you think? Share your own best gravy recipes in the comments…

So when flooded with queries from the public and RSC staff regarding the efficacy of conkers as a spider repellent, we shook ourselves dry and led the charge on a public scientific endeavour – to prove or dismiss the old wives’ tale that spiders really do hate conkers. For the best evidence (one way or the other) we’re offering a prize of £300.

We hypothesise that if it works there must be some chemistry in it. So the call went out to the public, through the illustrious pages of the Daily Telegraph, The Times and Daily Mail, various radio stations, and BBC Breakfast – and the public have responded with eyewitness accounts, photos, videos and even scientific experiments!

Let’s start with our own experiments. RSC staffer Will Russell cleared his busy schedule to spend part of his weekend taunting spiders with conkers and a control object (a table-tennis ball). The results were somewhat inconclusive – each spider reacted differently. Some good scientific methodology here: repeat experiments, a “control”, and the will to do a science experiment on the weekend.

Even Will’s rigorous experiments could not compare to those of Years 5 and 6 of Roselyon School in Cornwall, aided by teacher Mr Ferguson. The budding young scientists designed their own experiments with clearly-defined parameters for success, and demonstrated three of them on camera. They concluded that spiders weren’t bothered by conkers for the most part. Their video is below and well worth watching.

As I wade through the hundreds of letters and photos I’ve been sent, I’ll add more to the overall body of evidence. Below is a gallery of some of the more enlightening photos that we’ve been sent.

The media has happily announced the scientific community’s plans to colonise the Moon, with the recent discovery of significant quantities of water hidden away in Moondust (or whatever it’s called).

A refuelling station, or a full-blown colony for lunar settlers, seems almost within grasp… sort of.

Mark Henderson wrote a great piece in today’s Times titled “Water, water everywhere, but the Moon is still drier than a desert.” I read this as I was putting the finishing touches to my incredibly nerdy spreadsheet, and it verified my own calculations that colonising the Moon is still further away than we’d all hope.

Given that water is contained only within the top few millimetres of soil on the Moon’s surface (source: The Times), that there is a litre or so of water in each metre cubed of soil (source: Science) and that the average colonist would need roughly 4 litres per day to survive in relative comfort (source: a Battlestar Galactica discussion forum), I came up with the following rather arresting stats:

• For each “colonist”, a football pitch’s worth of soil would need to be processed every 16 hours
• This is 12 metric tons of soil
• For a year this is 6510 metric tons, or 545 football pitches
• After this time, at maximum walking speed on the Moon and assuming you worked outwards from your initial location, it would take you 13.4 minutes to walk the two-thirds of a mile to the edge so you could brush your teeth that morning
• It would take 10 million years for that person to use all the water on the Moon
• By this time he would be very lonely and probably not smell very fresh

This is all based on many variables pulled from all over the net, and some I’ve just made up – for example it’s based on 75% extraction efficiency. Who knows if that’s entirely over- or under-estimating what would be realistic?

It also completely ignores other uses for that water, as suggested by the media, such as being electrolysed for use as rocket fuel.

The spreadsheet is on Google Docs so anyone can have a go. Please feel free to fiddle about, and let me know if any of it’s completely wrong or you have better ideas. Any better estimations of the variables would be welcome, but one thing’s for sure: we aren’t going to have self-sustaining colonies up there any time soon.

link to the Google Docs Spreadsheet

A few of the favourites:

“It’s the water. The abundance of rain keeps people in and the best drinking water in the world keeps their minds refreshed and alert.” (via text).

“Scotland produces eminent scientists because claymores tend to discourage competition.” (via Twitter, @agoldson)

“Most came from working class. Learning was a commitment. Dedication & survival meant succeeding in ur chosen field.” (via text)

Praising the stoicism, intelligence or dedication of the Scottish people was a common theme. Also there were frequent references to the inclement weather – a heartfelt response from many Scots entering the competition.

So it’s only fitting that the winning entry is from a Scottish chemist, who had this to say:

“The weather keeps them in the lab during the day, whilst the whisky provides the inspiration at night.”

A poetic, succinct and quite possibly accurate submission from @littleghoti, who will soon be the proud owner of a black iPhone 3GS on O₂ Pay & Go.

O₂ is of course a chemist’s favourite mobile operator. Except maybe methyl Orange.

Monday afternoon’s plenary lecture was given by Prof. Dame Louise Johnson, who after her talk was awarded an honourary fellowship of the Royal Society of Chemistry.

Professor Dame Louise Johnson receives her Royal Society of Chemistry honourary fellowship from RSC President Dave Garner

In the evening Harry Kroto led a great Café Scientifique, talking about what he calls the “GooYouWiki World”, and a lot else besides! The house was full (sorry to those we had to turn away!) and everyone was up for questions and debate in the relaxed atmosphere of the Tron Theatre.

Café Scientifique at the Tron Theatre, Glasgow, with Harry Kroto

We talked a lot about education, particularly in the context of getting the best teaching resources to the teachers that need them most. Harry was keen to explain the benefits of the GeoSet project, too, where students can upload videos and synchronised presentations. “I’ve revolutionised marking,” Harry proudly proclaimed. “While other teachers have a huge stack of essays or papers to mark, I’m sitting at my table with a coffee watching the students on my laptop.”

Harry Kroto at the Tron Theatre