Image courtesy of DougsTech/Wikimedia D By EmmaDavis ideally, noplant tissues,meat,fishoreggs. milk proteins,alcohols,aminoacidsandflavour chemicals, and, dishes containingonlymethionaland‘pure’compoundssuch as Contest forNoteby NoteCooking. The challenge: tomake Methional played centrestageattherecentSecondInternational fried chicken From methionalto 44 tomatoes. asparagus, beer, cheddarcheeseand methional, anditisalsofoundin your nose’sodourreceptors iscalled hint ofbacon.Thechemicalhitting earthy smell,withanunderlying face bringswithitanunmistakeable I Science inSchool the steamthatrushes pastyour rain apanofboiledpotatoesand I Issue30: Autumn 2014

were awarded fordisheswithout and flavourchemicals.Extrapoints milk proteins, alcohols,aminoacids and other‘pure’ compoundssuch as dishes, allcontainingonlymethional The challenge:tomakeupthree by NoteCooking Second InternationalContestforNote nine playedcentre stageattherecent rivative from theaminoacidmethio The simple,sulfur-containing de- Me liquid withastrongsmellofcooked potatoes under ordinaryconditions,itis acolourless Im a

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f - H This plant tissues,meat,fishandeggs. clear goaltohuntoutthemechanisms molecular , whichhasa claim tothescientificdisciplineof physicist NicholasKurti,DrThislaid 1988, togetherwiththelateOxford concept of‘notebynote’.In tural Research, whocameupwiththe French NationalInstitutefor Agricul- using only‘pure’ can berecreated of friedchicken The contestwasorganised byHervé compounds O The taste w2 , aphysicalchemistfrom the www.scienceinschool.org Science topics

NIH omain/ lic d ub e p th in ge a Im Beer also contains methional Biology Physics technology Chemistry Biology Ages 14–18

Odours play an important Chemistry part in memory and can be strongly linked to experi- synthesiser you can make any music. ences. This is due to the ol- With ‘note by note’ you can factory receptors. This is the make any food.” key idea in making ‘’ Dr This envisages a time when we that bring the gastronomic will routinely assemble food from experience without the underlying cooking, tasting and eat- ingredients taken from jars and bottles primary animal and plant ing food. Chemistry and physics are in our . “‘Note by note’ will protein present. This article at its core. be the future,” he insists. “If the public could be used to stimulate The field spawned a generation wants and needs it, it will happen.” discussion on the world of inventive chefs who brought lab Importantly, he sees ‘note by note’ food shortage and how al- equipment, from rotary evaporators to as a solution to the inevitable food ternatives could be manu- water baths, into the . Liquid crisis that lies ahead as the world’s factured. How would the nitrogen hit the culinary scene, as did population continues to expand. manufacturers ensure that a host of tricks with gelling agents, One of the key advantages of this nutritional guidelines are producing soft gel pearls with a liquid type is cuisine is its ability to cut met? Students could inves- core packed full of flavour. transport needs. Dr This takes the example of tomatoes. When fresh, the tigate food labels, research ‘Note by note’ cuisine? the key chemicals that pro- fruit is heavy and water-laden. Why duce particular flavours, Initially intended to improve food, transport the water, asks Dr This. and study how flavourings ‘note by note’ cuisine soon morphed Instead, necessary nutrients and fla- are manufactured for foods to acquire the ambitious goal of mak- vours could be extracted at the farm – for example, how are po- ing dishes entirely from compounds, site and reintroduced when the to- tato crisp flavours made? Hervé This says. “I don’t want to matoes are needed. He compares this The concepts and science recreate anything. The proposal with process to transporting cheese instead of ‘note by note’ is to create new food.” of milk, or wine instead of grapes. could be discussed, as He equates the approach with using Dr This is almost evangelical about some chefs are now using a synthesiser to make music. “With a ‘note by note’ cuisine, and has been scientific techniques to ad- busy touring the USA and Europe to vance food preparation and spread the word. “The contest is one ology/Wikimedia echn of T presentation. ute stit In in bl REVIEW Dr Shelley Goodman, UK u D e th f o sy e Hervé This at Dub- rt u o c lin Institute of Tech- e g a nology, with a student m I demonstrating how to achieve a greater volume when whipping egg whites.

www.scienceinschool.org Science in School I Issue 30 : Autumn 2014 I 45

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Cheddar cheese is another food that contains methional

Image in the public domain/Jon Sullivan

of many pieces to implement ‘note by For Dr This, part of the challenge is low levels it can add an “appetising, note’ cooking for everybody,” he says. to persuade companies to sell ingre- cooked quality to fruits like apple, This year, it was a “big success”. dients such as methional directly to pineapple and pear”. Seventy-three contestants bat- the public. As it happens, methional tled it out for five prizes in different can already be purchased from lab So how does methional hit our categories. An undergraduate team suppliers for industry use. One, Sigma senses? studying molecular gastronomy at Aldrich, bills methional as being Only about one fifth of flavour the Dublin Institute of Technology, “toothsome” and able to comple- perception comes from the tongue’s Ireland, won the student prize with ment many savoury flavours. At very taste buds; most of the rest comes its novel roast chicken creationw3. This was developed in response to a specific challenge to make a dish Overview that is neither extraordinary nor ex- of the human olfac- travagant yet evokes memories. Their tory system. 1: Olfac- tory bulb 2: Mitral cells creation consisted of a wafer or tuile 3: Bone 4: Nasal epithe- of roast chicken, with a smattering of lium 5: Glomerulus 6: accompaniments. They made pow- Olfactory receptor dered ‘potato’ by mixing a methional neurons solution in oil with maltodextrin, citric acid and salt, and turned it into a potato meringue. This sat alongside rosemary caviar made from sodium Image courtesy of Ignacio Icke/Wikimedia alginate, and a roasted carrot tuile made by mixing powdered carrot with maltodextrin, , a gel and 1 water. The resulting gel layer was then dehydrated until it became crispy. 2 Next year’s contest will focus on plant protein, Dr This says. With 5 demand for meat soaring across 3 the globe, creating foods from plant proteins will become increasingly important, he says. 4 6

46 I Science in School I Issue 30 : Autumn 2014 www.scienceinschool.org Science topics Biology Chemistry

mons Com edia ikim /W 27 The m Formula m -b winning entry of this h l ja of -Methionine n e year’s contest for Note B f o by Note Cooking was y st e r a variation on roast u o c S chicken e g a

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Image courtesy of JMSchneid/Wikimedia

from smell. When we chew food, our mouths pump volatile molecules to O

the nose where they are met by hun- edia H N ikim 2 /W dreds of different odour receptors. ain om d ic Each receptor consists of a protein bl u p e OH h specially designed to create a pocket t n i e g for odour molecules to sit in. When a a m molecule activates a receptor, it trig- I gers an electrical signal that travels to the brain. receptors are found in receptor cells. Laboratories’ cen- In 2004, US scientists Richard Axel Each receptor cell contains only w4 trifuges are making and Linda Buck were awarded a one type of odour receptor and each a noteworthy entrance Nobel prize in physiology or medicine receptor can detect only a limited into restaurants’ for their discovery of odour receptors number of smells. The cells send kitchens. and the organisation of the olfac- signals directly to a region of the brain tory system. They discovered a large called the olfactory bulb, and on to family of about 1000 different genes other parts. Information from different that produce an equivalent number receptors combines to create an odour of types of olfactory receptors. These pattern.

ia ed im ik W n/ ai m o The d c li b ‘potatoes’ u p e h in the winning t n i e were a bit g a m I

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Image courtesy of umami/Flickr

of a restaurant

www.scienceinschool.org Science in School I Issue 30 : Autumn 2014 I 47 Gordon Shepherd, a neuroscientist He also has several other blogs Resource at Yale School of Medicine, USA, has where he writes about: worked on the olfactory bulb since - the science behind our usual The AgroParisTech’s International the 1960s. He calls the process of how cooking: http://­ Centre for Molecular Gastronomy the brain creates flavour ‘neurogas- gastronomie-moleculaire. was opened in June 2014; its director tronomy’. “Much of our brain power blogspot.de/ is Hervé This. See: is actually used to create flavours - science in general: www.agroparistech.fr/ and everything that goes with the http://hervethis.blogspot.de/ -Centre-international-de-.html flavours – memories, emotions and w3 – This article from New Scientist ______the language that we use to describe provides a good explanation of ‘note the flavours,” he says. He works on by note’ cooking, and mentions Emma Davies has a BSc in chemis- ‘odour images’ in the brain, which are the winners of this year’s contest: try and a PhD in food science. Before processed at the highest level, where www.newscientist.com/article/ embarking on a freelance career, perception occurs. mg22229722.900-chemical-cuisine- Emma worked for the Royal Society “The more we understand about poised-to-shake-up-food-chain. of Chemistry, where she was features how the brain creates flavour, the html?full=true#.U_3G2WO1S6Y editor of Chemistry World. more it will help us to understand w4 – To learn more about the Nobel how to encourage healthy diets,” he Prize awarded to Richard Axel and says. Linda Buck, see: www.nobelprize. Web references org/nobel_prizes/medicine/ laureates/2004/press.html To learn how to w1 – To read more about the 2nd use this code, see page 53. ardsley/Wi International Contest for Note by ott Be kimed f Sc ia y o tes Note Cooking in Paris, France, see: ur co e http://molecular-gastronomy- ag Im international.blogspot.de/2013/12/ the-second-international-contest-for. html w2 – Hervé This has gathered his work and all sorts of Liquid information related to molecular nitrogen ice gastronomy online, including cream material for teachers and ready- made lesson plans on this blog: https://sites.google.com/site/ travauxdehervethis/ Image courtesy of libsciterp/Flickr

Methional is part of the reason why the smell of cooked bacon is so ­attractive

48 I Science in School I Issue 30 : Autumn 2014 www.scienceinschool.org