SENSORY EVALUATIONSENSORY EVALUATION

SENSORY EVALUATIONSENSORY EVALUATION

Sensory - having to do with the senses of sight, taste, smell, hearing, touch - judgment of quality based on sensory data

Organolepsis - subject to judgment by the senses

Senses - the means of receiving all information

THE CHEMICAL SENSESTHE CHEMICAL SENSES

SIGHT- VISIONTASTE - GUSTATION SMELL - OLFACTION

MECHANICAL SENSESMECHANICAL SENSES

TOUCH - TACTILE SENSESHEARING - SOUNDKINESTHESIS - MOTIONEQUILIBRIUM - BALANCE

OTHER FACTORSOTHER FACTORS

Social and FamilyCulturalReligious beliefsNutrition and HealthEconomic and Marketplace factorsTechnological developmentsEmotional and psychological factors

SIGHT - VISIONSIGHT - VISION

Creates first impression Visual appeal - attractiveness Used to judge quality - ripeness,

freshness, concentration, defects, extent of cooking

VISUAL PROPERTIES OF VISUAL PROPERTIES OF FOODFOOD

Color Transparency or opaqueness Dullness or gloss Size Shape Amount Defects, decay, infestation

TASTE TASTE

Detects water soluble chemicalsTongue - taste “buds” located in

the papillaeSubstance must be dissolved in

water or salivaFlavor – combination of taste and

odor – complex mixture

FIVE TASTESFIVE TASTES

Sweet - Due to alcohol (OH) groups, detected quickly, on the tip of tongue

Salty-Sodium ion modified by Chloride, detected quickly, on tip of tongue

Sour-Acid, due to hydrogen ions, detected on side of tongue

Bitter-taste buds at back of tongue Umami-savory, glutamate that occurs

naturally in food.  Some examples of these foods are parmesan cheese, bacon bits, soy sauce, meat, ketchup,  from flavor enhancers such as MSG

TASTE SENSITIVITYTASTE SENSITIVITY

Taste affected by other stimuliTime: Location of taste budsThreshold-Concentration required for

substance identificationSub-threshold-Substance not

identified, but will affect perception of another taste

EFFECT OF SUB-THRESHOLD EFFECT OF SUB-THRESHOLD SUBSTANCESSUBSTANCES

Salt Increases sweet, decreases sour

SourIncreases salty, decreases sweet

SweetDecreases salt, decreases bitter

TEMPERATURE AND TASTETEMPERATURE AND TASTE

Affects flavor, warm foods taste stronger and sweeter than cold foods

Salt stronger in warm foodsVolatility of substances increase at

warm temperatures, so they smell stronger-pungency

Taste buds most receptive at temperatures between 68-860F

PSYCHOLOGICAL FACTORSPSYCHOLOGICAL FACTORS

Flavor perceptions based on color, color intensity, texture (thickness)

General health and well-beingTime of dayAdaptation-Previous exposure to

substance, especially salt tastes (salt and resalt foods)

OLFACTORY - SMELLOLFACTORY - SMELL

Ability to detect chemicals dissolved in air

Aroma impacts on tasteDon’t taste greasy, chocolate, mint –

smell, mouthfeel, or combination

TEXTURE - TACTILETEXTURE - TACTILE

Qualities felt with fingers, tongue, palate, teeth

Index of qualitySmoothness, stickiness,

graininessCrispness, crunch

TASTE AND AGETASTE AND AGE

Varies over the lifespanHighest taste sensitivity occurs in

babiesNumber of taste cells in humans

declines with ageSerious decline in taste cell numbers

begins ~45 y.o. By 70 greatly lowered ability to taste

SENSORY TESTINGSENSORY TESTING

Analytical -Laboratory evaluation, used in early stages of product development, objective evaluation

Affective - Consumer evaluation to measure acceptance and preference

DIFFERENCE TESTS ACCEPTANCE/PREFERENCE TESTS DESCRIPTIVE TESTS

DIFFERENCE TESTSDIFFERENCE TESTS

Determine perceivable difference between products

Changing ingredients or source of ingredient

Check quality of product over time Check shelf life of a product Triangle test-three samples, two alike,

determine the odd sample Duo-trio test- match the reference product

ACCEPTANCE/PREFERENCE ACCEPTANCE/PREFERENCE

Paired Preference-choose preferred item Ranking-rank preference Rating - Absolute Judgment Hedonic – measures how much liked or

disliked Food Action – would you eat or buy

DESCRIPTIVE TESTSDESCRIPTIVE TESTS

Trained panelistsDifference between productsHighly specialized tests

ANALYTICAL EVALUATIONANALYTICAL EVALUATION

Uses equipmentSprectrophotometer - colorConsistometer - consistencyViscometer-viscosity

COMPARING SUBJECTIVE & COMPARING SUBJECTIVE & OBJECTIVE EVALUATIONSOBJECTIVE EVALUATIONS

Subjective/sensory Uses individuals Involves human

sensory organs Results may be

variable Determines human

sensitivity Determines customer

acceptance Time consuming,

expensive Essential for product

development

Objective analysis Uses equipment Uses physical,

chemical techniques Results are repeatable Need to find

technique appropriate for food

Cannot determine consumer acceptance

Faster, cheaper, more efficient

Essential for routine quality control