First published in the Financial Times on 8th July 2014.
What we learn as children in the class room can play an unexpected role in adult life
My favourite subject at school was chemistry but I never imagined that one particular biochemical reaction would dominate my career. Yet so it has proved. And that almost magical natural event is called fermentation. It shows how what we learn in the classroom can play an unexpected role in adult life.
This fantastic process underlies the production of not just alcohol, but bread too – and indeed pizza. Under anaerobic conditions, certain single-cell fungi called yeast will convert carbohydrates into a variety of products. For bread the dough is leavened with baker’s yeast, then allowed to rise (or proofed). This step releases carbon dioxide into the dough, as well as a complex mix of other compounds such as ketones, alcohols, aldehydes and esters. Many of these are evaporated by subsequent baking. Others impart particular flavours and consistency to the crust and crumb of the bread.
There is something transcendent in seeing flour transformed via fermentation and baking into a delicious loaf, be it a ciabatta, baguette or bloomer. Bakers at both my companies Patisserie Valerie and Gail’s take simple ingredients and transform them into delicacies produced via fermentation, ranging from croissants to muffins to cupcakes. And I have been involved with countless restaurants, from PizzaExpress to Rocket, that take flour, water, yeast, salt, cheese and tomato and transmute them into enticing pizza.
Of course, fermentation does not just create leavened bread: it also generates delicious and occasionally dangerous alcoholic drinks such as wine, beer and cider. Again, yeast reacts with fruit or grains to break down sugar into alcohol – refreshing and enlivening people all over the world – and sometimes making them drunk. A marvellous new book called Proof, The Science of Booze, by Adam Rogers, gives chapter and verse on how the biology of ethanol production works, whether brewing, vinification or distilling.
I have been in the business of selling fermented drinks for more than three decades, from nightclubs, pubs, restaurants, sports stadiums, hotels and bingo halls – among other outlets. Unsurprisingly, it was that great Frenchman, Louis Pasteur, who discovered that microbiotic activity in yeast creates alcohol; after all, in 1965, they drank 160 litres of wine per head in France. Today that figure has fallen by two-thirds. But they probably still understand the art and science of fermentation better than anyone.
Fermentation might have played the pivotal role in the initial development of farming and domesticating crops by early man. According to archaeologist Patrick McGovern, 9,000 years ago humans turned from hunter gatherers and settled – in order to make alcoholic beverages. Rather more recently, fermentation helped create the modern drug industry. Close to my home in London, Sir Alexander Fleming, a colleague of my late grandfather, discovered penicillin in 1928 in the labs at St Mary’s Hospital. But he could not produce enough for medical use. In 1941 the Allied governments asked pharmaceutical corporations to discover the means to mass produce the antibiotic to save troops’ lives.
Charles Pfizer & Co, then a small chemical company based in Brooklyn, tried fermentation. They had pioneered its use to manufacture citric acid, a natural preservative, in large quantities. Led by researcher Jasper Kane, the company used more than a dozen giant tanks full of thousands of gallons of “fermentation liquor”. By early 1944 it had definitively industrialised the production of antibiotics; within years it was also making streptomycin and on its way to becoming one of the world’s largest pharmaceutical concerns.
Today I use a little of my school chemistry and even my physiology degree to understand my role chairing The Institute of Cancer Research, a world-beating centre for drug discoveries. Of course, much of what I studied decades ago is irrelevant to my daily work. But I am regularly surprised at how knowledge acquired over the journey of life can prove valuable in unexpected ways. We should all be life-long learners, constantly enquiring, remaining interested in the world. Those who adopt this philosophy stay young and more productive, and are much better company than people with closed minds.