This document discusses methods for analyzing food flavor, including both chemical and instrumental techniques as well as sensory testing. It describes how solid phase extraction and solid phase microextraction are used to separate compounds from liquid mixtures. Gas chromatography, gas chromatography-mass spectrometry, and gas chromatography-olfactometry are instrumental methods discussed for analyzing food flavor compounds. Sensory testing techniques involve using the senses of smell, taste, sight and include preference tests, discrimination tests, and ranking tests to evaluate attributes like flavor.

2. INTRODUCTION
 “Flavor is the sensation produced by a material taken
in the mouth, perceived principally by the sensesof
tasteand smell, and also by the general pain and
temperaturereceptors in the mouth.”
 “ Flavor is one of the three main sensory properties
which are decisive in the selection, acceptance, and
ingestion of a food.”

3. Stimulus Senses Sensory Response
Taste
Food Flavor
Odor

4. CHEMICAL METHODS
 SOLID PHASE EXTRACTION:- Compounds thatare
dissolved orsuspended in a liquid mixtureare
separated from othercompounds in the mixture
according to theirphysical and chemical properties
 SOLID-PHASE MICROEXTRACTION, OR SPME:-
# A sample preparation technique used both in the
laboratoryand on-site
# A very shortgas chromatographycolumn turned
inside out

5. INSTRUMENTAL METHODS
 GAS CHROMATOGRAPHY (GC)
 GAS CHROMATOGRAPHY-MASS SPECTROMETRY (GC-
MS)
 GAS CHROMATOGRAPHY-OLFACTROMETRY (GC-O)

6. GAS CHROMATOGRAPHY
 WIDELY USED ANALYTICAL TECHNIQUE
 EXCELLENT SEPARATION POWERS AND EXTREME
SENSITIVITY
 LOW SAMPLE CAPACITIES
 IMPOSSIBLE TO DEDUCE THE OVERALL SAMPLE
ODOR THRESHOLD
 TWO DIMENSIONAL GC (GC XGC)

8. DETECTORS USED
FID
NPD
ECD
TCD
PID
FPD
PFPD

9. GC-MS

10. GC-O

11. SENSORY TESTS
It involves useof senses (physiological response):
 Olfactoryreceptors
 Taste receptors
 Visual receptors

12. SENSORY TESTING TECHNIQUES
 Preference test - whetherpeople likeordislikea product.
E.g.:



Hedonic scale
Paired comparison tests
Scoring
 Discrimination test - todescribea particularattributeof a
product. e.g.
 Triangle test
 Duo trio test
 Ranking

13. Hedonic scale
 Samples given in a random order
 Testers have to rank in orderof preferenceof a specific
quality ( e.g. Salty taste)
 Minimum of 10 testers required togiveaccurate results

14. Scoring
 Food samplesare scored on a scale, between dislikeand
like.
 Testers are allowed toevaluatesamplesand score.

15. Triangle test
 Consists of THREE samples – 2 IDENTICAL/ 1
DIFFERENT
 Testers need to IDENTIFY the DIFFERENT SAMPLE
 More efficientthan paired comparison

16. Duo trio test
 Consists of THREE samples – 2 IDENTICAL/ 1 DIFFERENT
 Using one of the two identical samplesas a control, testers
are allowed todecidewhich of the other tworemaining
samples is the sameas the control.

17. Ranking test
 Decided on theattribute to be ranked, e.g. crunchiness.
 Testers are allowed toevaluatesamplesand place them in
rank orderaccording to the presenceorabsence of the
attribute from ‘very’ to ‘notatall’
.

18. OTHER TESTS
It includes:
 Threshold test
 Intensityrating test
 Time-intensity test
 Descriptive test
 Consumertest
 Qualitycontrol test

19. ANY QUERIES???