CSAR Cambridge 19 May 2014 Peter Barham - Department of Physics, University of Bristol, UK - Department of Food Science, University of Copenhagen, DK - Animal Demography Unit, University of Cape Town, RSA Molecular Gastronomy The Science of Taste and Flavour

2 Where did it all start Molecular Gastronomy has its origins in a series of workshops for chefs and scientists held in Erice in Sicily initially suggested by Elizabeth Thomas and organised by Nicholas Kurti. The meetings were called “International Workshops on Physical and Molecular aspects of Gastronomy”. Later abbreviated to Molecular Gastronomy.

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4 What is Molecular Gastronomy? Today, we want to understand what it is that makes one dish delicious and another not; whether it be the choice of ingredients and how they were grown; the manner in which the food was cooked and presented; or the environment in which it was served.

5 Taste sensations Salt Sweet Bitter Sour Umami X We each have five different types of taste buds distributed around the tongue and the sides of the mouth. Salt an essential nutrient we would not get in a ‘natural’ diet Sweet the taste of sugars needed to provide bursts of energy Bitter the taste of alkaloids – potentially toxic substances Sour the taste of acids – possibly dangerous Umami the taste of an essential nutrient – amino acids Particularly the taste of the sodium salt of glutamic acid Also known as mono (sodium glutamate) Or MSG

6 Perception of Flavour Flavour is the combination of taste in the mouth (from the taste buds) and aroma in the nose. Our noses are very much more sensitive than our tongues – we have around 400 different types of aroma sensor compared to just 5 types of taste sensors.

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8 Adaptation Our sense of smell evolved to help us know what is in our environment. We thus are more sensitive to changes in the aromas around us. This means that we quickly ”adapt” to aromas – ignoring constant smells. In food, constant flavours become “boring” and are ignored. Perception of Flavour

9 How can we describe flavour? In practice flavour is constructed in our minds. We use all our senses to determine flavour. What we see tells us what to expect. A white wine coloured red will evoke red wine memories and descriptions. The colour of the plates on which we serve food affects expectations and thus appreciation. Food served on blue plates often has a poorer rating than food served from.

10 Perception of Flavour What we hear affects how we eat. Try recording yourself eating a crunchy food and then play the sound back while trying to eat something soft. Or take some chips and simply crush then in your hands near the ears of a ‘friend’ who is trying to eat! If you listen to music when eating, you are liable to start to chew in time to the beat.

11 Perception of Flavour What we feel affects how we perceive texture. Try eating a creamy food (maybe a yogurt) – note how creamy you think it is. Take a second spoonful while stroking a smooth silky surface – it will probably seem creamier. Take a third spoonful while rubbing your and with sandpaper – the food will probably seem a little gritty.

12 Combinations of Flavour Generally when two foods go well together they share some chemical constituent – the origin comes from noting that there is a single molecule whose aroma is evocative both of Gruyere cheese and honey Tomorrow’s World challenged us a few years ago to come up with a novel combination – based on mass spectrographs of 10 ingredients. Blue cheese and Chocolate – dessert at Fat Duck Web site foodpairing.be Looking at lists of important flavour molecules can suggest novel flavour combinations. Coffee and Garlic (Noma) Chocolate and Caviar (The Fat Duck) Goats cheese and Beetroot (Casamia)

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