1. The Elements of Taste Flavor in Fruits and Vegetables
Chuck Marr
K-State Research and Extension
Horticulture

2. A New Area of Study Anatomical and sense in 1920s and 1930s
Organoleptic differences
Modern ‘sensory analysis’ began in 1950s
First 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.

3. Topics Difference between taste and flavor
How we perceive taste and flavor
Differences among us
Measuring or predicting flavor
Some ways we can determine flavor differences

4. Taste We are able to taste only 4 things
Sweet
Sour
Salty
Bitter
These are sensed in specific locations on the tongue

5. Taste sensation areas on the tongue
Bitter
Sour
Salty
Sweet

8. Moves into taste bud in liquid (saliva or juice)
Initial taste fades quickly- must be rejuvenated with a new movement of liquid

9. Trigeminic Receptors or “Pain Receptors” in the mouth
Hot- (Capsaicin in hot peppers, mustard oil in radish, mustards)
Cold- (Menthol, cucurbitacin in cucumber)
Astringent (Pucker in persimmon)
Induce a pain response.
Tolerance varies among individuals.
May build up a resistance

10. Taste- A little controversy
We are able to taste only 4 things
Sweet
Sour
Salty
Bitter
Orientals claim to taste another
Umami (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.

11. Taste Combinations Sweet-Sour Sweet- Salty Sugar Acid Ratio
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

12. Taste vs Flavor Taste- those 4 tastes determined by the tongue
Flavor= 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.

13. 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.

14. Flavor Aroma May be able to sense prior to entering the mouth.
May activate or excite the tasting process= “mouth watering” saliva formation anticipating a pleasant taste sensation
Lots of pleasant and unpleasant sensations- some very closely related

15. Important volatile compounds influencing flavor
Aromatic compound group- example compound= edible crop example
Hydroxy compounds- geosmin=“earthy”
Aldehydes- hexenal=apples
Ketones- 2,3 butanedione=celery
Acids- acetic acid=vinegar
Esters- methyl anthranilate= Concord grape
Sulfur compounds- dimethyl sulfide=asparagus
Oxygen hetrocycles- furaneol= pineapple
Nitrogen hetrocycles- pyroles= peppers
Sulfur heterocycles- thiophenes= fried onion
Other compounds- iodine=edible seaweed

16. Aroma as part of food flavor
Compounds that form the primary flavor of a fruit or vegetable are called “character-impact compounds” There are several classes of foods where these compounds can be identified and duplicated.
Largely 1 compound
Mixture of a small number of compounds
Large number of compounds- no single one
Foods that number of compounds is so large or complex that we can’t duplicate

17. Some foods with character-impact compounds
Single compound
Banana, lemon, pear, cucumber, pepper
Small number
Apple, raspberry, tangerine, celery, onion, tomato
Large number
Peach, lime, pineapple, walnut
Very complex-not easily duplicated
Strawberry, chocolate

18. Flavor complex in tomato
Sugars
Volatile flavor compounds
hexanal
trans-2-hexanal
cis-3-hexanal
cis-3-hexen-1-ol
2-isobutylthiozole
Acids (primarily citric)

19. Saturation when additions don’t create a sense of increases
May become disagreeable or cause you to lose sensation if concentration is too great
Taste Sensation Increases
Threshold when you can first sense
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.
Concentration of Taste or Flavor Element

20. Differences Among Us Age Age dulls the senses
Youth- sweet
Older- bitter
Age dulls the senses
Illness or physical limitations (colds, etc)
Male vs female
Musk aromas sensed differently
Ethnicity or background
What we like established by what we’re exposed to
“Life Altering Experiences”

21. Sensory Analysis Methods
Trained ‘taste panel’- 3-5
Expert panel- 5-10
Consumer preference 40-50

22. Quantifying Sensory Analysis
Triangle test (3 samples- 2 the same)
Hedonic ratings (1-10 scale)
Offer several sub questions
Taste, color, texture, eye appeal, etc
Be very specific in establishing the questions
How used, family likes, economy, etc

23. Several other components of flavor
Texture or ‘mouth feel’
Grainy, mushy, crunchy, slimy, chalky
Color
Appealing color for the product
Both these factors are independent of taste or flavor but contribute to our determinations of sensory quality.

24. Predicting Sensory Quality
pH- acidity
Optimum size or maturity index
Refractometer (sugar content)
Instron ‘shear press’ (tenderness)
Chromatography (gas or liquid)