When is a Strawberry No Longer a Strawberry?

You take that first bite, tearing through the cells of the red berry and allowing its fragrance to erupt. Juices ooze, coating your mouth. The sweetness, modulated with a slight bitter hint, hits your tongue and lights up your senses, and the distinctive flavour of the strawberry overflows.

Why do we love strawberries so much?

Why do we love strawberries so much? There’s something alluring about them, something intense and complex in the flavour we experience that is not matched by any other berry – its chemistry.

When we recognise a flavour – the combined experience of taste, mouth feel and (crucially) smell – we are actually recognising the aromatic chemistry of a food, the volatile molecules given off when we bring it close to our nose or after we bite into it. When we understand the molecules that make up the distinct chemical profile of a flavour, we can replicate it by creating those chemicals in a lab and stirring them together. This helps us make artificial banana flavour, artificial vanilla flavour, and artificial fresh grass smell. But strawberries are awkward. Strawberry flavour is made up of a chemical medley of many, many different molecules (more than 350), variation exists strawberry species to strawberry species, and we just don’t know how important each chemical is.

This is in direct contrast to the raspberry, a humble berry that we recognise as 4-(4-hydroxyphenyl)butan-2-one, or “raspberry ketone”. Whilst cranberries and blackberries also contain this odour, they mix it with other chemicals, whilst in the raspberry it is exclusively responsible for the raspberry profile we instantly know.

Raspberry ketone, the molecule behind the smell we know so well. © Things We Don't Know.

Food for Thought; the Future of Global Food?

A global food shortage may not appear to be a threat or worry for a lot of people; around half a billion have been diagnosed as obese, that’s 1 in 14 people worldwide^[1]. However, with an estimated 1 in 9 people being malnourished, in many countries the threat is already a reality. Though numbers predicted vary, the global population was agreed to have breached 7 billion people by 2012^[2]. Most estimates point to another 2 billion people on the planet by the middle of the century. To put that increase into perspective, when we reached the first billion by 1804 it took around 156 years to add 2 billion. At our current rate of growth, an addition of the same number again will happen more than five times faster.

The prevalence of malnourishment and obesity across the globe, and the disparity between the two. South-east African countries appear most malnourished, whilst levels of obesity rose in almost every country last year. Image credits: Undernourishment by country (top) via wikimedia [CC BY-SA 3.0], obesity by country (bottom) from Institute for Health Metrics and Evaluation [CC BY-NC-ND 4.0]