This document discusses various techniques used in sensory evaluation of food products. It describes five human senses - sight, hearing, touch, taste, and smell - that are used to scientifically analyze foods. It then focuses on computer-aided sensory evaluation techniques, including electronic nose (e-nose), electronic tongue (e-tongue), texture profile analysis, electronic eye (e-eye), and biosensors. These computer tools are presented as more accurate and cost-effective alternatives to human sensory panels for objectively measuring attributes like texture, aroma, and taste.

1. M.Sc Food technology
Submitted to – Dr. Anil Chauhan
Submitted by – Ramkinker Gupta

2. 
 Sensory evaluation is a scientific discipline that analyses and
measures human response to the composition and nature of
food products.
 Sensory Evaluation does not deal with likes and dislikes, ok or
not ok but the process scientifically elicits , measures ,analyses
and interprets physiological response to physical stimuli by a
food products.
 It is a scientific discipline perceived by senses of sight , smell,
taste, touch and hearing.
Sensory Evaluation

3. 
 There are five sense in human being used for sensory
evaluation :
 Sight : Ability of eye and brain to detect electromagnetic waves
and interprets image for detection of sensory properties of foods.
 Hearing : Senses of sound is perceived by ear using vibrations .
 Touch : Senses of pressure perception , texture analysis of food
products using skin.
 Taste :The taste buds are present in tongue that identify taste of
food products. Our tongues distinguish between five basic tastes
such as sweet , sour, salty, bitter and umami.
 Smell : The sense of smell also called olfactory senses serves to
perceive aromas of different food products using chemo-electrical
transduction.
Human Senses

4. 

5. 
 Training and employees maintenance is very costly issue which
can be overcome by using computer aided sensory evaluation.
 This gives accurate measurements as compared to panel
members.
 Initial investment and maintenance of computerized sensory
assessment lab will repay in long run in terns of planning,
efficiency and cost effective.
Need for computer aided sensory
evaluation :

6. 
 There are specially designed hardware and softwares for
sensory evaluation of food products.
 Computer have different detectors like colour, texture, E –
Nose, E- tongue, and sound detectors which work similar to
human senses.
Computer aided sensory
evaluation

7. 
 The electric nose is a device which detect the smells more
effectively than human senses of smell.
 It consist of sensor array, pattern reorganization modules, and
headspace sampling to generate signal pattern that are used for
characterizing smells.
 An electronic nose consist of mechanism for chemical detection.
It uses an array of gas sensor which are overlapping with a
pattern reorganization component.
 When a specific sensor receives the molecules , it transmit the
signals to a program for processing .
E - Nose

8. 
Cont…
 The electric nose consist of three major components which are
detecting system , computing system and sample delivery
system .

9. 
 An electronic tongue is an instrument which comprises of
electrochemical cell , sensor array and appropriate pattern
recognition system capable of recognizing non volatiles
materials which forms taste of samples.
 The sensor array consist of potentiometric metal based
electrodes .
 A taste sensor is composed of several lipid membranes for
transforming information of taste into an electric signal.
 The output of electronic tongue shows different pattern for
chemical substance which have different taste qualities .
E - Tongue

10. 
Cont…

11. 
 TPA is a popular test for determining the textural properties of
foods.
 During a TPA test, samples are compressed twice using a
texture analyzer to provide insight into how samples behave
when chewed.
 The TPA test is called two bitting test because texture analyzer
mimics the mouth bitting action.
 The TPA is an analytical method which can quantify multiple
textural parameters such as hardness , cohesiveness ,
adhesiveness etc.in just one experiment.
Texture profile analysis

12. 
Cont…
 Fracturability – first significant break in the curve
 Hardness – force exhibited in first bite at max compression
 Cohesiveness – ratio of positive areas under first and second
compression
 Adhesiveness – work required to pull the plunger away after
first compression
 Springeness – ratio of length of compression in the 2 and 1
plunge
 Stringiness – distance for which product is extended during
decomposition before separation of probe
 Gumminess – hardness * cohesiveness
 Chewiness – gumminess * springiness

13. 
Cont…

14. 
 E – eye has proven to give a fast , accurate and cheap
evaluation of food , shape , size, colour and brightness.
 The e – eye system is based on different elements light source,
camera, computer with software and high resolution monitor.
 Camera is used for capture the image.
 LED , halogen , sodium lamps are used as light source.
 The characteristics of sample surface can scatter or reflect the
light by which sample evaluation can be done.
Electronic - eye

15. 
 A biosensor is an analytical device containing an immobilized
biological materials such as enzyme , antibody etc.
 Biological materials interact with an analyte and produce
physical , chemical and electrical signals that can be measured.
Biosensor

16. 
 https://www.elprocus.com/electronic-nose-work
 https://globalresearchonline.net/journalcontents
/volume5issue2/Article- 017.pdf
 Aust, L. B. (1984). Computers as an Aid in
Discrimination Testing Food Technology,
 Breer, H. (1997). Sense of smell: signal recognition
and transductions in olfactory receptor neurons. In:
Handbook of Biosensors and Electronic Noses:
Medicine
References

17. 
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