Descriptive Sensory

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1*1 cinad 19 SM A^cu,^e LibraryK&?5adienneJiagricultureAUGfti? 1 5 I9S7 C , A

Research BranchTechnical Bulletin 1997-2E

Descriptivesensory

analysis:The profiling

approach

Canada


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Cover illustrationThe images represent the Research Branch's objective:to improve the long-term competitiveness of the Canadianagri-food sector through the development and transfer of newtechnologies.Designed by Research Program Service.Illustration de la couvertureLes dessins illustrent I'objectif de la Direction generale de larecherche : ameliorer la competitivite a long terme du secteuragro-alimentalre canadien grace a la mise au point ct au transferde nouvelles technologies.Conception par le Service aux programmes de recherches


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Descriptivesensory analysis:

The profilingapproach

L.E JEREMIAH, L.L. GIBSON andK.L. BURWASHResearch CentreLacombe Alberta

Technical Bulletin 1997-2E

Research BranchAgriculture and Agri-Food Canada

1997


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Copies of this publication are available fromDirectorLacombe Research Centre6000 C&E TrailLacombe, AlbertaT4L 1W1

Her Majesty in Right of Canada as Represented byPublic Works and Government Services Canada 1997Cat. No. A54-8/1997-2EISBN 0-662-25-963-7Printed 1997


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SUMMARYAt the point of consumption, palatability or eating satisfaction is the primary determinant of consumer acceptability.Palatability is determined by the flavor and texture of the food product. The flavour and texture of a food productare determined by their components (character notes) and the arrangement (order of appearance), and intensity ofthese components. Consumers are primarily interested in the overall palatability, texture, and flavour of a foodproduct and the extent to which these properties meet their personal expectations for that particular food product.However, in research and product development it is often necessary to look beyond overall palatability, texture, andflavour and evaluate the individual components of these properties in a similar fashion by which art and music areevaluated. This can be accomplished by using descriptive sensory analysis and the profiling approach to foodtexture and flavor. This bulletin provides details regarding the profiling approach, character notes, intensity, orderof appearance, aftertastes and afterfeelings, and amplitude (overall impression).

RESUMEA l'6tape de la consommation, la palatability determine l'acceptation du consommateur pour un produit alimentaire.La palatability est deTinie comme e tant la flaveur et la texture du produit. et celles-ci sont determiners par lescomposantes (notations de tendrete), Parrangement (l'ordre d'apparition) et l'intensite de ces composantes. Leconsommateur est principalement interesse par la palatability, la texture et la flaveur g6nrale d'un produitalimentaire et jusqu'a quel point le produit satisfait a son attente. Lors du d^veloppement d'un produit alimentaire,plus particulierement au niveau de la recherche, il est souvent utile de voir au dela de la palatabilite, de la texture etde la flaveur afin d'6valuer les composantes individuelles de chacune de ces proprtetes, comme on le fait pour^valuer les arts ou la musique. Ceci peut etre accomplie, en utilisant une analyse sensorielle descriptive et enetablissant des profils pour ^valuer la texture et la flaveur. Ce bulletin, offre une information dtaill6e sur les profils,les notation de tendrete, l'intensite, l'ordre d'apparition, la persistance gustative, l'impression rsiduelle etl'amplitude (impression g6n6rale).


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http://archive.org/details/descriptivesenso19972jere


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Table of Contents

Background 1Character Notes 2

Aroma 2Flavour 2Taste 2

Mouthfeelings 3Texture 3

Hardness 4Cohesiveness 4Springiness 4Viscosity 4Adhesiveness 4Fracturability 4Gumminess 4Geometrical Characteristics 5

5of Appearance 6

and Afterfeelings 7Amplitude 7

Profiling Approach 8Background 8The Approach 8The Panel 9The Results 10


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B ackgroundSensory evaluation is the qualitativeassessment of a material based upon

perceptions arising from sensations detected by theeyes, ears, nose, tactile nerves, and/or taste buds.Such perceptions are formulated by the brain whichanalyzes the interaction of sensations resulting fromthe stimulation of various receptors (i.e. the eyes,ears, nose, tactile nerves, and taste buds).The use of humans in sensory evaluation of aroma,flavour, and texture is necessary because nomechanical device can measure the perceptionformulated by the human mouth, nose, and brain.However, when humans are utilized for sensoryevaluation it is necessary to rigidly control all testingethods and conditions to eliminate potential biases

arising from psychological factors.anels utilized in sensory evaluation can consist ofighly trained experts, experienced laboratoryersonnel, or untrained consumers. In general, highlyrained and/or experienced laboratory panels aretilized to describe factors contributing to the qualityof a product, while consumer panels are employed toestimate consumer response to a product.There are three basic questions to be answeredhrough sensory evaluation:

1) Is there a detectable difference between foodsamples?Answered by difference tests utilizingpsychophysics and a laboratory panel

) How well do people like a food product?Answered by consumer preference tests utilizingpsychometrics

3) What are the palatability attributes of a foodproduct?

Answered by profile panel tests utilizingphenomenological description

Descriptive analysis is considered to be the mostsophisticated sensory evaluation method presently inuse, and is the only method that deals with the totalperception of a product. The three most popularmethods of descriptive analysis are flavour profiling,

texture profiling, and quantitative descriptiveanalysis.

Descriptive analysis requires at least 3 evaluationprocesses including discrimination, description, andquantification of individual characteristics.Discrimination is the detection of those

characteristics that contribute to the overallflavour, aroma, and texture.Description is the process of describing each of these

character notes using meaningful commonlanguage and terminology. Discrimination anddescription together provide a definition of thequalitative aspects of a product or those notesthat combine to make a product what it is.

Quantification is the process of determining theintensity and order of appearance of eachcharacter note.

Therefore, descriptive analysis is a complexcognitive process requiring more mental acuity thansharp taste and olfactory senses, since sensory stimulimust not only be detected, but must also bedescribed.By definition descriptive analysis seeks to describeand analyze all perceived characteristics of aroma,flavour, and texture. Therefore, it is essential thatsuch sensory data be as objective and as free fromopinion as possible. This necessitates the use ofstandard terminology, standard reference samples,and standard evaluation procedures to aid ineliminating subjective judgments from panel data.Appropriate language is developed through carefultraining and practice, during which the paneldevelops a common vocabulary or a flavour, aroma,and texture mental library which catalogues varioussensory stimuli with appropriate names.Flavour and texture profiling are two of the mostpopular methods of descriptive analysis.Flavour profiling is the sensory analysis of the aromaand flavour complex of a food product in terms

of its aromatics, basic tastes, and mouthfeelingsensations, the degree of each present, and theorder in which they appear from the initialsensation to residual sensations remaining afterthe sample has been swallowed.

Texture profiling is the sensory analysis of the texturecomplex of a food product in terms of itsmechanical, geometrical, and fat and moisturecharacteristics, the degree of each present, andthe order in which they appear from the initial


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mouthfeeling to residual sensations remainingafter swallowing.

the dimensions of the profile method

character notes or perceptible aroma, flavour,and texture factorsdegree of intensity of each factororder in which these factors are perceivedaftertastes or afterfeelingsamplitude or overall impression

haracter Notes

are the detectable parameters that definethe flavour, aroma, and texture of a

and include:components ofaroma composed of olfactorysensations perceived by the olfactory nerve andnasal feelings perceived by the tactile nerves inthe nosecomponents offlavour by mouth composed ofolfactory sensations perceived by the olfactorynerve, taste sensations perceived by the tastebudson the tongue, mouthfeel sensations perceivedby the tactile nerves in the mouth and nose, andafterfeel/aftertaste sensations or taste, olfactory,and/or feeling sensations remaining afterswallowingcomponents oftexture composed of mechanicalsensations perceived by the kinesthetic sense asreactions of the product to stress, geometricalsensations perceived by the tactile nerves in themouth related to size, shape and arrangement ofparticles, fat and moisture sensations perceivedby the tactile nerves in the mouth related to thecontent and reaction of fat and moisture withinthe product, and afterfeel sensations perceivedafter swallowing (geometrical and/or fat andmoisture sensations).

are only two types of senses: chemical sensessmell, and feeling), and physical senses (sight

sound).is the odor sensation of a substance perceived

olfactory and tactile nerves in the nasal cavityby direct sniffing through the nostrils or

through the passage at the back of the

mouth, including both odor and feeling factors.Olfaction is the sense of smell or the perception ofodors by nerve cells in the nasal area. Odors areperceived by the olfactory cells located at the upperregion of the nasal cavity, but only a small portion ofany substance reaches the olfactory region.Obstruction of air passages in the nasal cavity cangreatly reduce olfactory perception. Since the top ofthe throat and the nasal cavity are joined odors can beperceived through the pharynx as well as through thenose. Anosmia is odor blindness.Components of aroma are either olfactory sensationsperceived by the olfactory nerve (fruity, floral,rancid, sulfury, etc.) or nasal feelings perceived bythe tactile nerves in the nose (cool, pungent, etc.).

Aroma is normally evaluated before flavour sinceodor notes may be overpowered or masked when thefood is eaten.

Flavour by mouth consists of taste factors, feelingfactors, aromatic factors, and aftertastes orafterfeelings. Identity of a food flavour dependsupon the concentration of specific chemicals releasedduring eating and the specific sensitivity of theconsumer. Components of flavour by mouth areeither:

1 taste sensations perceived by the taste buds onthe tongue (sweet, salty, sour, bitter)

2) mouthfeel sensations perceived by the tactilenerves in the mouth (cool, metallic, hot, cold,astringent, etc.)

3) aromatic sensations perceived by the olfactorynerve (vanilla, fruity, floral, etc.)

4) aftertaste sensations (aromatic, taste, and/orfeeling factors) perceived after swallowing thatresemble those prior to swallowing.

Flavour results from chemical stimulation of the tastebuds in the mouth, the olfactory nerve and organs inthe nose, and the nerves and organs of feeling in themouth throat, and nose. Only a portion of thechemicals in a given food will be sensed. Forexample, brewed coffee flavour is readily recognizedbut only bitter and sour can be tasted, onlyastringency felt and only the bouquet aromadetected.

Taste is the sense by which certain properties areperceived through taste buds on the surface of thetongue. There are only four tastes; sweet, salty, sour,


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bitter. These are often referred to as basic orfactors, since physiologists have shown that

these sensations will stimulate the taste buds.tastes are sensed on different surfaces of the

Sensitivity is mostly on the edges of theand not in the middle.

Bitter

Sour

Salt

Sour

Salt

Sweetare the bumps on the tongue and are of four

foliate, circumvallate, fungiform, and filiformtaste buds). Some papillae are known to respondto one taste stimulus than to another. However,

manner in which taste buds react to stimuli is notknown.

influencing taste perception are diseaseaguesia (taste blindness), temperature,

used (solid or liquid), viscosity, number ofsensations present, and chemical configurationdifferent isomers may differ in the amount of

they elicit).

effect of temperature varies for differentDifferent flavour factors are sensed

and at different times, although the totalspan may be only microseconds. Each

flavour has its own time-intensity curve.ever, most flavour sensations build up rapidly to

peak and then dissipate rapidly.

are sensations perceived by the nervesthe skin of the mouth cavity resulting from thermalchemical reactions. Thermal reactions result inof hot and cold.

Example 1= ice (thermal cold)Example 2= hot water (thermal hot).

Chemical feeling factors are less well definedphysiologically.Example 3= cayenne pepper (chemical hot or bite)Example 4= peppermint candy (chemical cool)Example 5= ferrous sulfate (metallic)Example 6= spearmint gum (green)Example 7= horseradish (chemical burn)Example 8= club soda (prickly)

Therefore, flavour is all of the sensations of taste,smell, and feeling when a food is being consumed.

Texture is the sensory manifestation of the structureor inner makeup of foods. The components oftexture are:

1) mechanical sensations perceived by thekinesthetic sense as a reaction of the product tostress; such as hardness, cohesiveness,brittleness, chewiness, gumminess, viscosity,springiness, and adhesiveness

2) geometrical sensations related to the size, shape,and arrangement of particles perceived by thetactile nerves in the mouth; such as, powdery,chalky, grainy, gritty, coarse, lumpy, beady,flaky, fibrous, pulpy, cellular, aerated, puffy,crystalline, stringy, smooth, etc.

3) fat and moisture sensations related to the contentand reaction of fat and moisture perceived by thetactile nerves in the mouth; such as, moistness,oiliness, moisture release, moisture absorption,and saliva thickening

4) afterfeel sensations such as, geometrical or fatand moisture sensations remaining as residuesafter swallowing.

Order of appearance in texture evaluation is fixed.Surface characteristics are evaluated first, thencharacteristics perceived on partial compression andthe first bite are evaluated, such as elasticity,hardness, compressibility, cohesiveness, etc.Characteristics perceived during mastication are thenevaluated such as, chewiness, moisture absorptionand release. Afterfeel sensations are evaluated afterswallowing.The texture of samples rarely differs due to the orderof appearance of character notes. Occasionally one


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will disappear more quickly then another, butwill be accounted for by evaluations of

chewiness, and rate of disintegration,

mechanical characteristics consist ofcohesiveness, viscosity, springiness, and

All primary mechanical characteristicsadhesiveness are related to forces of attractionbetween particles of food and opposing

Adhesiveness is related to surface

is the force required to compress abetween the molar teeth (in the case of

or between the tongue and palate (in the casesemi-solids). Hardness is evaluated by placing a

between the molar teeth and biting downevaluating the force required to compress the

Intensity of hardness:Soft - Firm - HardPeanuts - Carrots - Almonds - Rockcandy

is the degree to which a substance isessed between the teeth before it breaks.

is evaluated by placing a samplethe molar teeth, compressing it, and

the amount of deformation before rupture.Intensity of cohesiveness :

Easy to disintegrate - Hard to disintegrateTaco chips - Carrots - Bread - Meat

is the degree to which a product returnsits original shape once it has been compressed

the teeth. Springiness is evaluated bythe sample between the molar teeth, if a

or between the tongue and palate, if a semi-compressing it partially and then removing theevaluating the degree of quickness of recovery

Intensity of springiness:Plastic (easily molded) - Elastic

Taffy - Carrots - Bread - Meatis the force required to draw a liquid from a

over the tongue. Viscosity is evaluated bya spoonful of sample directly in front of theand drawing the liquid from the spoon over

tongue by slurping, evaluating the force requireddraw the liquid over the tongue at a steady rate

Intensity of viscosity:Thin - Thick - Viscous

Water - Orange juice - Karo syrup - HoneyAdhesiveness is the force required to remove thematerial that adheres to the moth (generally thepalate) during the normal eating process.Adhesiveness is evaluated by placing the sample onthe tongue, pressing it against the palate, andevaluating the force required to remove it with thetongue.

Intensity of adhesiveness:Sticky - Tacky - Gooey

Carrots - Rock candy - Bread - Peanut butterSecondary mechanical characteristics consist offracturability, chewiness, and gumminess andcontribute to cohesiveness.Fracturability is the force with which a samplecrumbles, cracks, or shatters. Fracturability isevaluated by placing the sample between the molarteeth and biting down evenly until the food crumbles,cracks, or shatters, evaluating the force with whichthe food moves away from the teeth.

Intensity of fracturability (Brittleness):Crumbly Crunchy Brittle

Meat - Peanuts - Granola bars - Taco chipsChewiness is the length of time in seconds requiredto masticate a sample at a constant rate of forceapplication to reduce it to a consistency suitable forswallowing. Chewiness is evaluated by placing asample in the mouth and masticating it at one chewper second at a force equal to that required topenetrate a gum drop in 54 second, evaluating thenumber of chews required to reduce the sample to astate ready for swallowing.

Intensity of chewiness:Tender - Chewy - Tough

Cheese - Meat - Licorice - TaffyGumminess is the denseness that persists throughoutmastication or the energy required to disintegrate asemi-solid food to a state ready for swallowing.Gumminess is evaluated by placing the sample in themouth and manipulating it with the tongue againstthe palate, evaluating the amount of manipulationnecessary before the food disintegrates.


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Intensity of gumminess:Short - Mealy - Pasty - Gummy

Butter - Cream cheese - Cottage cheese - Peanut buttercharacteristics are related to the size

shape of particles (gritty, grainy, etc.) perceiveddiscrete particles relatively harder than the

medium or carrier, or are related to theand orientation of the particles (fibrous, flaky,in highly organized structure of different

arrangements within the product.ticle size and shape:

Chalky - Gritty - Grainy - Coarseshape and orientation:Fibrous - Cellular - Crystalline= dusty, friable, or in the form of power

Example = confectioner's sugar= having a chalk-like texture

Example = raw potato, tooth powder= granular, consisting of grains

Example = cream of wheat, farina, wheatlettes= sandy, containing grit

Example = sand, pears= consisting of rather large particles

Example cooked oatmeal= covered with or full of lumps

Example = cottage cheese= full of or covered with drops or bubbles

Example = tapioca pudding= containing or made up of flakes

Example = boiled haddock= containing or composed of fibers

Example = breast of chicken= containing or composed of pulp

Example = raw orange sections= consisting of or containing discrete cells

Example = raw apple, white cake= containing pockets of air

Example = chiffon pie filling, marshmallows

Puffy = puffed, swollen, inflatedExample = puffed rice

Crystalline = consisting of or composed of crystalsExample = granulated sugar

Stringy = consisting of strings or tough fibersExample = celery

Other textural characteristics are related to theperception of moisture and fat. Moisture is evaluatednot only for the amount present, but also for the rateand manner of absorption or release. Fat is evaluatednot only for the amount present, but also for its typeand rate of melting.

Moisture content: Dry - Moist - Wet - Watery

Fat type: OilinessGreasiness

I ntensityIntensity is the degree to which each characternote is present in the sample being evaluated

and represents one of the quantitative aspects of theproduct. Intensities can be expressed or quantitatedusing several scaling procedures including: 1)category scales, 2) linear scales, and 3) magnitudeestimation.A category scale is a set of equally spaced categoriesanchored with numbers and adjectives into which aseries of stimuli must be fit. A linear scale is astraight line of fixed length which may or may nothave anchor points on which the panelist marks thedistance representative of the intensity in question.Magnitude estimation is a ratio scale.With magnitude estimation the intensity of a givenstimulus is assigned a positive number and theintensities of other stimuli in the same or othersamples are assigned numbers in proportion to thefirst rating given. The first rating may be of thepanelist's choice or may be fixed by the panel leaderusing reference samples of fixed intensity. Thusmagnitude estimation can be used either with orwithout a fixed modulus. However, when themodulus is not fixed the data must be normalized tofacilitate comparisons among panel members andpooling of panel data.


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it is either desirable or necessary to compare ordata over panel sessions or to compare the

of one characteristic to another, the panelbe trained to rate intensities across

For example, one lemonade may be10 for sweetness, while another lemonade may

rated 15 for sweetness to reflect a sweetness 1.5as strong. In the same context, chocolate

dding and apple pie of equal sweetness wouldsweetness ratings of equivalent intensity.

lemonade with a sweetness and a sourness ofintensity would receive equivalent ratings forsweet and sour.products may have identical qualitative traits or

of aroma, flavour by mouth, and texture,the same description or definition, but may differto the intensity of certain components.

is the point on a stimulus scale at which aoccurs in a series ofjudgments. Absolute

detection threshold (AL) is the level of stimulus ata transition occurs from a lack of sensation to

Recognition threshold (RL) orthreshold is the minimum level of

at which a substance can be correctlyDifference threshold or just noticeable(DL) is the least amount of change in

which produces a change in sensation.threshold (TL) is the amount of stimulus

which increases in intensity can not beThere are about 25 just noticeablein tastes and odors from recognition

to terminal threshold. Above this pointoften occurs.

indicating that the lemon drink was twice as sweet asthe lemonade.

AL RL DL DL TL

A B C Dcannot measure with precision taste intensitiesthe recognition threshold unless standards are

levels differ among individuals. Twowith recognition thresholds for sucrose of

and 0.40% may report a 10% sucrose solution tomoderately sweet. However, a moderate sweet

(10) should be the same in lemonade as it is inLikewise, sweetness, sourness, and vanilla

perceived to be equal in intensity shouldthe same intensity ratings. For example, if aassigns a rating of 10 to the sweetness of a

lemonade, he might assign a rating of 20 to theof a carbonated lemon drink, thus

order of AppearanceThe order in which differentcharacteristics are perceived can be defined. In somecases the order of appearance of the character notesmay constitute one of the most important factorscontributing to differences in overall impression.This is particularly true in the case of flavour sincethe order of appearance of most texture characternotes is predetermined by the evaluation process.Therefore, texture rarely differs due to the order ofappearance of character notes. Occasionally, onesample will disintegrate more rapidly than another,but this difference will usually be accounted for inratings of chewiness, rate of breakdown, etc.If the exact order of appearance flavour characternotes cannot be determined, character notes can beclassified as appearing early, middle, and late.The texture profile procedure follows.During the initial phase or before biting into thesample or manipulating it in the mouth, geometricaland fat and moisture characteristics associated withthe surface are perceived. These include surfacemoisture, surface roughness (smoothness), thepresence of surface particles having a particulargeometrical characteristic, etc.During partial compression with the molar teeth orthe tongue and palate, elasticity or springiness areevaluated.During the first bite with the molar teeth mechanicaland geometrical characteristics are perceived, as wellas moisture and/or fat release and absorption.During mastication (chewing) all textural propertiesare perceived. Particular attention should be given tomoisture and fat absorption and release and to theappearance of or changes in different geometricalcharacteristics.

During the residual phase all geometrical and fat andmoisture characteristics remaining after the samplehas been swallowed are perceived. Particularattention should be given to mouth dryness, oiliness,ease of swallowing, etc.


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ftertastes and Afterfeelings

When a bite of food is eaten or a sip ofis drunk the entire sensation of flavour and

usually lasts only a few seconds. However,foods and beverages even after being

leave a flavour or texture residue termedor afterfeelings.is not a miniature of the whole flavour in

cases, but may well be just delayed effects such asdryness, or long-lasting factors such as

mplitude

Attempts are often made to measure theor total impression of flavour and texture

they are multivariate systems. However, theof ratings of overall impression that can be

is dependent upon the extent of training thehas received with regard to the evaluation and

of factors constituting the total

highly trained panel can rate the overall intensityflavour and texture, with some difficulty, by

all of the character notes, and theirThe difficulty arises since the intensities

the individual character notes are not additive.sensations interact to produce patterns or

which are not properties of thesensations themselves, but rather a

of the way they are arranged or organizedthe interaction. Therefore, the overall flavour

cannot be considered to be a composite ofindividual sensations.

amplitude of both flavour and texture is oftenwhen a profiling approach is utilized to reflect

blendedness and appropriateness of all of theracter notes present and their intensities and orderappearance. Appropriateness of the character notesdetermined by what character notes are expected topresent in a given product. For example, orange

is expected to have fresh orange aroma,sourness, etc. Likewise saltiness is

in potato chips but not in strawberry jam.if saltiness is detected in strawberry jam,

particularly at high intensity, it would detract fromthe flavour amplitude. Balance and blendednessrefers to the relative balance of the character notespresent, in relation to what is expected for a givenproduct type. For example, if a given character note ,even though appropriate, is too weak or too intense itwill detract from the amplitude. Hence, if alemonade is too sour or has too weak of lemonaromatic this will detract from the flavour amplitude.Therefore, in a sense, amplitude ratings reflect anevaluation of the overall product quality.

However, the problem in analyzing amplitude is nothow to measure it, but rather how such data can beinterpreted and utilized. For example, if a product isgiven high flavour and/or texture amplitude ratingsby a group of sensory experts, does this implyconsumer acceptance? The answer is no, sinceconsumers do not always prefer products that are themost fresh, most natural, most well blended, and/ormost free from offnotes.

A trained panel can also be asked to rate the overalldifference between a given sample or product and acontrol, reference, or standard sample or productprovided the panel has an in-depth understanding ofthe total frame of reference in which the samples arebeing evaluated. Hedonic rating are only meaningfulwhen they are provided by an untrained consumerpanel or a carefully selected semitrained laboratorypanel. Panels intensively trained to objectivelyanalyze the components of aroma, flavour, and/ortexture should never be asked to provide hedonicratings.

Amplitude constitutes the overall impression of theproduct including the appropriateness of the variouscharacter notes and their intensities during all phasesof evaluation. Amplitude in a sense is an evaluationof the overall quality of a product, but amplituderatings must not reflect personal or consumerpreferences, since consumers do not always preferproducts that are the freshest, most natural, or mostwell blended.

Determination of amplitude or overall flavourimpression depends upon rating of the balance, theblendedness and appropriateness of thecharacteristics and their intensities. It requires a firmknowledge of the place each product fits into the total


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of reference. For example, does an orangehave fresh orange character, sweetness,

etc.? Are these characteristics properlyand is the product well put together in

to other orange juices?

amplitude or overall flavour intensity ison the combination of aromatics, basic tastes,

and aftertastes.general, product flavours with two or more high

characteristics will generally be rated highermore intense in amplitude than those with severalintensity characteristics.

Profiling Approachackground

Flavour and texture perception is not aof individual sensations since individualinteract to produce patterns or

which are not properties of thesensations themselves, but rather a

of the way they are arranged or organized.example, when viewing a painting we usually donotice the individual brushstrokes, but the

whole. Likewise, when listening to music,are not so aware of the individual notes as we aremelody. When we eat a steak we are not as

of the hardness or compressibility of thefibers, or the cohesiveness or coarseness of

meat as we are the tenderness. We can lookthe initial perception and analyze the

elements (i.e. brushstrokes, notes,etc.) and learn something about the

and arrangement of the whole.palatability of food products can be analyzed and

in much the same manner in which art andare analyzed and evaluated. For example, theimpression created by a painting is evaluated

well as each individual brushstroke, and theof music in evaluated as well as each

note. Likewise with profiling the overall(amplitude) of flavour and texture is

as well as all individual character notes,intensities, and their order of appearance.

the profiling approach looks beyond theperception and analyzes individual elements so

that the organization and arrangement of the wholecan be understood. The flavour profileaccommodates both the overall impression created byflavour and aroma and the individual elements thatcontribute to that impression. The texture profileaccommodates both the overall impression created bytexture and the individual elements that contribute tothat impression.Thus, since analysis and synthesis are both inherentto the perception process, they are both incorporatedinto the flavour and texture profile. The flavour andtexture profile can be visualized as an open hand withthe palm being the body and the extended fingersrepresenting the individual flavour and odor notesthat emerge. When one or more of these notes iseither suppressed or non-existent the profile haschanged. The composite (whole hand) represents thewhole flavour or the amplitude. For example, theflavour profile of brewed coffee contains the body(palm of the hand) represented by unidentifiablechemicals which make coffee - coffee withoutcreating a flavour impression; and the individualnotes (fingers) represented by the sour, bitter,astringency, and bouquet notes.T he ApproachThe trained profile panel first developsappropriate terminology and definitions and fortexture decides on the order in which characteristicsare to be evaluated.With both flavour and texture profiling a frame ofreference is developed by the panel itself for eachproduct type to be evaluated. The panel thendiscusses the appropriateness of the terminology toprovide all of the panelists with equal understandingof the definition of descriptive terms for thequalitative notes and the methodology to be utilizedfor evaluating samples and quantifying intensitiesand order of appearance, and to remove duplicationand extraneous evaluations from the profile. Oncethe panel has developed the profiling procedures andadequately defined their common terminology,evaluations of a product can begin.To develop appropriate terminology, panelists shouldindividually evaluate several samples representativeof the full range of flavours and textures for aparticular product type and list all of the terms thatapply to one or all samples. These terms are thendiscussed and a mutually acceptable list of terms and


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are developed, considering theof the list, whether some terms have

same meaning and can be combined or deleted,the degree of consensus on each term and

independently evaluate one sample at a timerecord all character notes perceived, their order

appearance, and their intensities and assign ato amplitude. After 2 or 3 samples have been

independently, the panel assembles as ato discuss their evaluations and to develop a

profile for each sample. Therefore,and texture panels function as teams, evensamples are evaluated independently and allare professionals, since group perception ismore comprehensive than individual

he Panel

Reliability and reproducibility of flavourtexture profile data is dependent upon the skill ofpractitioners and the use of objective reference

to eliminate discrepancies. Profiles areand utilized through experience which

perceptual judgments of both the elementsstructure of flavour, aroma, and texture by

carefully selected and intensively trainedpractitioners working as a team to reach a compositejudgment. Therefore, profiling requires professionalskills and experience and generally relies on resultsrather than statistics to confirm previous findings.The panelists' objective is to become proficientenough to be able to write down accurate worddescriptions of texture, flavour, and aroma, and theoverall impression or amplitude after 3 sniffs and/or3 bites and to be able to answer the followingquestions:

1) Was the amplitude low, medium, or high?2) What were the discernible factors?3) How strong was each of these factors?4) Which came first, second, third, etc.?5) What were the aftertastes and/or

afterfeelings?

Such proficiency is gained through both broad andintensive training lasting up to one year. Suchproficiency and training enables the formation of acomplete flavour/texture profile with texture, aroma,and flavour by mouth described and specified asaccurately as possible, including amplitude or overallimpression, and description of detectable factors,their intensities, and order of appearance.

Componentscomponents of both the flavour and texture profile are depicted and compared in the following table.

Components Flavour TextureCharacter notes

IntensityOrder ofAppearance

Olfactory sensationsTaste sensationsNasal sensationsMouthfeeling sensationsDegree of each note presentQuite unpredictable andvariable

Aftertaste/AfterfeelingAmplitude

Mechanical characteristicsGeometrical characteristicsFat and moisture characteristics

Degree of each note presentFollows a definite sequence,including the following phases:

InitialPartial compressionFirst biteMasticutoryResidual

Sensations perceived after swallowing Sensations perceived after swallowingOverall impression (balance blendedness and appropriateness of individual character notes)


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he Results

The validity and accuracy of panelis related to:

1) reliability of the panel as a whole toduplicate findings from one evaluation toanother

2) the ability of individual panel members toduplicate their findings from one evaluationto another

3) the ability of panel members to agree withone another

profiles consist of descriptions of thecharacteristics or character notes, theirtheir order of appearance, and a rating ofSuch profiles of food products can be

with profiles for other products or productshave been processed or treated differently.since flavour and texture perception is not

composite of individual sensations, but rather aof the patterns and configurations produced

the interaction of individual sensations, theof the individual sensations and their(intensities and order of appearance) to

another and the types of interactions theyare the most important components ofand texture perception reflected in completeTherefore, it is essential that complete

be presented and compared, sinceor deletion of one or more of the

notes or their properties alters the profilemay result in misrepresentation of the data.

flavour and texture profiles can bein tabular or graphic form and can bestatistically. However, most industrial

utilizing the profile approach prefer not totheir data to statistical analysis.


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Descriptive Sensory

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