“Why One Person’s Taste Bliss is Another Person’s Poison"

Prof. Tony Blake

“How Human Beings Learn to Like the Flavours of Foods and Drinks"

Prof. Tony Blake

…..of the fruit of the treewhich is in the midst of the garden, God hath said, yeshall not eat of it, neither

shall ye touch it, lest ye die.

....but in spite of this warning Eve was typically human.

Humans are the only animalswhich cook and process thefoods they find…………

…...and in this way create new flavors which never existed before in Nature.

Humans eat the foods which they have created through their methods of cooking and cuisine.

The flavors of these foods are dependent on the cooking processes used and are

consequently man made.

In human history there have been continualchanges in food and flavor preferences

The Evolving Scientific Base of the Flavor IndustryThe Evolving Scientific Base of the Flavor Industry

19th Century 20th Century 21st Century

Solvent Extraction Molecular Separation Physical Chemistry

Steam Distillation Identification Biochemistry

Fractional Distillation Synthetic Organic Chemistry Human Physiology

For most of the 20th Century the focus of the Flavor Industry was the identificationof those molecules which give odor and

taste to food and drinks

1950 to 1990

New analytical techniquesallowed these molecules to be identified at lower levels

and with increasing precision

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OHO

S

O

S S

O O

O O

S S

Flavor Authenticity depends:

• not only on having the correct molecules

• but also an appropriate delivery system

• and the correct dynamics of delivery

In 1990 Firmenich purchased the Californian company MCP

They had an enviable reputation in organic chemistry but lacked

the science base for understanding the new products acquired with this acquisition

A Case Study in Flavor Release

Control of flavor release was an important

marketing claim but one which couldn’t be

quantified in the most important situation….

….during the eating of food.

In 1996 at the University of Nottingham Prof. Andy Taylor and Dr. Rob Linforth

developed a technique for real-time, in vivo analysis of flavor release from food and

this allowed a new understanding of flavor dynamics and the effects which food structure and composition have on its

perception.

AROMA

sweet

sour

PROFILE

bitter

umami

salty

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Sucrose Release

Menthone Release

Time-Intensity

Courtesy of J. Davidson & A J Taylor. The University of Nottingham

From Breslin et al

Aroma-chology Review, vol. X n°2, pp14-17 (2002)

Almonds are not sweet

Mint leaves are bitter!

What do we taste each day that is minty and sweet?

Our association of flavor and taste is learned.

What exactly is flavour ?

However, brains act in a holistic way...

… and we needed to get inside consumer’s heads

Magnetic Resonance Imaging

fMRI brain scans of people engaged in either hearing (blue)or silent lipreading (red). Common activity is shown yellow.From Calvert et al 1997.

Learning and Cross Modal Connections

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The most plausible way to explain the inter-sensory

effects we had observed is to conclude that ‘flavour’ is

in fact a construct of the brain…….

.. and it is a learned response

> 80% of the input data is from breath from the mouth passing over the

olfactory bulb in the nose,

but what we see, how it feels,how it tastes, what we hear and

our pleasure and satisfaction will allinfluence the way we remember it.

Flavour is a multi-sensory memory…..

…….which depends on our personal experiences of eating and drinking…...

Conscious

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All our senses play a part in flavor perception

Flavor Processing: more than the sum of its parts.

Small, D., Jones-Gotman, M., Zatorre, M.P. and Evans, A.C.

NeuroReport 8, pp 3913-3917 (1997)

Flavor processing is not represented by a simple convergence of its component senses….changes (seen

with PET imaging) in the amygdala and basal forebrain suggest a role for these structures in

processing novel or unpleasant stimuli.

Zampini, M. and C. Spence (2004 ).

“The role of auditory cues in modulating the crispness and staleness in crisps.”

Journal of Sensory Studies 19, 347-363.

Flavor is Nature’s way of letting food and drink

communicate with us…

…it tells us whether we can swallow what is in our mouth

or if we should spit it out.

…..and we start learning about flavor very early in our lives, several months

before we are born.

This baby already has flavour

preferences which started to develop

seven months before it was born.

Electron micrographshowing the extentand complexity of

connections betweenneurons in the human

brain.

Length of connections in the brain cortex in micrometres

Taken from “Consciousness” Rita Carter 2002.

At birth 3 months 15 months 2 years

Development of dendritic connections between neurons

Girl left with half a brain is fluent in two languages

The Daily Telegraph, May 23, 2002

The Importance of Associative Learning

One would be hard-pressed to find a developmentalneurobiologist who does not agree that early

experiences, especially between mother and infant, influence the pattern of brain connections in

ways that fundamentally shape our future personality and mental health.

Professor Mark SolmsChair of NeuropsychologyUniversity of Cape Town

South Africa

Our brains do not have the capability to form conscious memories until after the age of two, but the development of the

brain in those first two years will greatly affect future attitudes, prejudices and

behavior:

- this will include future preferences for foods, drinks and their flavors.

The liking of wintergreen flavour

depends on nurture not nature

What does wintergreen remind you of ?

Muscle-warming liniment or anti-septic ointment ?

Human beings like to experiment.

Monell Chemical Senses LaboratoryPhiladelphia

Dr. Gary Beauchamp

Professor Leann Lipps BirchCenter for Childhood Obesity Research

Prof. John PrescottJames Cook University

University of Cairns Australia

Odor-Taste Interactions: Effects of Attentional Strategies during exposure.

Prescott, J., Johnstone, V., Francis, J.Chemical Senses 29, pp 331 - 340, (2004)

Professor Fergus Lowe

Dr Martin Yeomans

Sutton Bonington Campus of theUniversity of Nottingham

Reproduced from

The making of culinary tradition in Japan”

J.K. Cwiertka. 1999

Balut

The Philippino Delicacy

In which category do

you fit ?

There is much that we do not understand about the human brain; the way it determineswhich foods and flavours we like is just one

of the areas open for study.

Flavour in foodEdited by

A Voilley, Université de Bourgogne and P Etievant, INRA, France

Woodhead Publishing 2006