The Elements of TasteThe Elements of TasteFlavor in Fruits and VegetablesFlavor in Fruits and Vegetables

Chuck MarrChuck Marr

K-State Research and ExtensionK-State Research and Extension

HorticultureHorticulture

A New Area of StudyA New Area of Study

Anatomical and sense in 1920s and 1930sAnatomical and sense in 1920s and 1930sOrganoleptic differencesOrganoleptic differencesModern ‘sensory analysis’ began in 1950sModern ‘sensory analysis’ began in 1950sFirst book on ‘sensory analysis’ in 1959First book on ‘sensory analysis’ in 1959

Taste or flavor characteristics of fruits and vegetables not very important in the ‘selection factors’ used by plant breeders until recently. Now being factored in along with other characteristics.

TopicsTopics

Difference between taste and flavorDifference between taste and flavorHow we perceive taste and flavorHow we perceive taste and flavorDifferences among usDifferences among usMeasuring or predicting flavorMeasuring or predicting flavorSome ways we can determine flavor Some ways we can determine flavor

differencesdifferences

TasteTaste

We are able to taste only 4 thingsWe are able to taste only 4 thingsSweet Sweet SourSourSaltySaltyBitterBitter

These are sensed in specific locations on These are sensed in specific locations on the tonguethe tongue

Sweet

Salty

Sour

Bitter

Taste sensation areas on the tongue

Moves into taste bud in liquid (saliva or juice)

Initial taste fades quickly- must be rejuvenated with a new movement of liquid

Trigeminic Receptors or “Pain Trigeminic Receptors or “Pain Receptors” in the mouthReceptors” in the mouth

Hot- (Capsaicin in hot peppers, mustard oil Hot- (Capsaicin in hot peppers, mustard oil in radish, mustards)in radish, mustards)

Cold- (Menthol, cucurbitacin in cucumber)Cold- (Menthol, cucurbitacin in cucumber)Astringent (Pucker in persimmon)Astringent (Pucker in persimmon)

Induce a pain response.

Tolerance varies among individuals.

May build up a resistance

Taste- Taste- A little controversyA little controversy

We are able to taste only 4 thingsWe are able to taste only 4 thingsSweet Sweet SourSourSaltySaltyBitterBitter

Orientals claim to taste anotherOrientals claim to taste anotherUmami (you mommy)- GlutamateUmami (you mommy)- Glutamate

Evidence is that it appears to be a legitimate taste factor; however, it is unknown where the taste is sensed on the tongue.

Taste CombinationsTaste CombinationsSweet-SourSweet-Sour

Sugar Acid RatioSugar Acid RatioSweet- SaltySweet- Salty

We can mask or alter some tastes by combinations with others. For example, we can make taste less sour by adding sweet…. Actual acidity or sweetness levels may not be exact reflections of what we taste.

Taste + Trigeminic Responses

Sweet - Hot

Taste vs FlavorTaste vs Flavor

Taste- those 4 tastes determined by the Taste- those 4 tastes determined by the tonguetongue

Flavor= Taste + Aroma or SmellFlavor= Taste + Aroma or Smell

While we can only determine 4 taste factors, it is estimated that we can differentiate over 10,000 aromas or flavors in foods.

Aroma is sensed in the nasal passages and usually is a volatile or aromatic compound that moves into the nasal chamber.

Aroma is slower to respond that taste because it’s beyond the tongue.

Flavor AromaFlavor Aroma

May be able to sense prior to entering the May be able to sense prior to entering the mouth.mouth.

May activate or excite the tasting process= May activate or excite the tasting process= “mouth watering” saliva formation “mouth watering” saliva formation anticipating a pleasant taste sensationanticipating a pleasant taste sensation

Lots of pleasant and unpleasant Lots of pleasant and unpleasant sensations- some very closely relatedsensations- some very closely related

Important volatile compounds influencing flavorImportant volatile compounds influencing flavor

Hydroxy compounds- geosmin=“earthy”Hydroxy compounds- geosmin=“earthy” Aldehydes- hexenal=applesAldehydes- hexenal=apples Ketones- 2,3 butanedione=celeryKetones- 2,3 butanedione=celery Acids- acetic acid=vinegarAcids- acetic acid=vinegar Esters- methyl anthranilate= Concord grapeEsters- methyl anthranilate= Concord grape Sulfur compounds- dimethyl sulfide=asparagusSulfur compounds- dimethyl sulfide=asparagus Oxygen hetrocycles- furaneol= pineappleOxygen hetrocycles- furaneol= pineapple Nitrogen hetrocycles- pyroles= peppersNitrogen hetrocycles- pyroles= peppers Sulfur heterocycles- thiophenes= fried onionSulfur heterocycles- thiophenes= fried onion Other compounds- iodine=edible seaweedOther compounds- iodine=edible seaweed

Aromatic compound group- example compound= edible crop example

Aroma as part of food flavorAroma as part of food flavorCompounds that form the primary flavor of Compounds that form the primary flavor of

a fruit or vegetable are called “a fruit or vegetable are called “character-character-impact compounds” impact compounds” There are several There are several classes of foods where these compounds classes of foods where these compounds can be identified and duplicated.can be identified and duplicated.Largely 1 compoundLargely 1 compoundMixture of a small number of compoundsMixture of a small number of compoundsLarge number of compounds- no single oneLarge number of compounds- no single oneFoods that number of compounds is so large Foods that number of compounds is so large

or complex that we can’t duplicateor complex that we can’t duplicate

Some foods with character-impact Some foods with character-impact compoundscompounds

Single compoundSingle compound Banana, lemon, pear, Banana, lemon, pear, cucumber, peppercucumber, pepper

Small numberSmall number Apple, raspberry, Apple, raspberry, tangerine, celery, onion, tangerine, celery, onion, tomatotomato

Large numberLarge number Peach, lime, pineapple, Peach, lime, pineapple, walnutwalnut

Very complex-not easily Very complex-not easily duplicatedduplicated

Strawberry, chocolateStrawberry, chocolate

Flavor complex in tomatoFlavor complex in tomato

Sugars

Acids (primarily citric)

Volatile flavor compounds

hexanal

trans-2-hexanal

cis-3-hexanal

cis-3-hexen-1-ol

2-isobutylthiozole

Tas

te S

ensa

tion

Incr

ease

s

Concentration of Taste or Flavor Element

Threshold when you can first sense

Saturation when additions don’t create a sense of increases

May become disagreeable or cause you to lose sensation if concentration is too great

No 2 people may be the same in when the threshold occurs or when saturation occurs or how long saturation lasts until a decline starts.

Differences Among UsDifferences Among Us AgeAge

Youth- sweetYouth- sweet Older- bitterOlder- bitter

Age dulls the sensesAge dulls the senses Illness or physical limitations (colds, etc)Illness or physical limitations (colds, etc) Male vs femaleMale vs female

Musk aromas sensed differentlyMusk aromas sensed differently

Ethnicity or backgroundEthnicity or background What we like established by what we’re exposed toWhat we like established by what we’re exposed to

““Life Altering Experiences”Life Altering Experiences”

Sensory Analysis Methods

Trained ‘taste panel’- 3-5

Expert panel- 5-10

Consumer preference 40-50

Quantifying Sensory AnalysisQuantifying Sensory Analysis

Triangle test (3 samples- 2 the Triangle test (3 samples- 2 the same)same)

Hedonic ratings (1-10 scale)Hedonic ratings (1-10 scale) Offer several sub questionsOffer several sub questions

Taste, color, texture, eye appeal, Taste, color, texture, eye appeal, etcetc

Be very specific in establishing Be very specific in establishing the questionsthe questions

How used, family likes, economy, How used, family likes, economy, etcetc

Several other components of flavorSeveral other components of flavor

Texture or ‘mouth Texture or ‘mouth feel’feel’ Grainy, mushy, Grainy, mushy,

crunchy, slimy, chalkycrunchy, slimy, chalky

ColorColor Appealing color for the Appealing color for the

productproduct

Both these factors are independent of taste or flavor but contribute to our determinations of sensory quality.

Predicting Sensory QualityPredicting Sensory Quality

pH- aciditypH- acidity Optimum size or maturity indexOptimum size or maturity index Refractometer (sugar content)Refractometer (sugar content) Instron ‘shear press’ Instron ‘shear press’

(tenderness)(tenderness) Chromatography (gas or liquid)Chromatography (gas or liquid)