Ningappa Kirasur

Dept. of Olericulture

2014-12-129

Acceptance-preference test

• Appearance of a food is the most important rather vital aspect

of sensory evaluation

• It is based on the visual appearance and palatability of the

product

• Their main objective is to determine the consumers’

acceptance of certain food products

• Acceptance and preference tests are widely used at the

development and launching stages of new products

Introduction

Types of sensory testing

A .Difference test B. Rating test/ preference test

C.Sensitivity test Descriptive test

A1. Paired comparison test

B2. Duo- Trio test

A3. Triangle test

B1. Ranking testB2. Single sample (monadic) testB3. Two-sample difference testB4.Multiple sample difference

testB5. Hedonic rating test.B6. Numerical scoring testB7. Composite scoring test

C1. Sensitivity threshold testC2. Dilution test

1. Ranking test

Used to determine how several samples differ on the basis of

a single characteristic

Panelist are presented all samples with code number and are

asked to rank

The Panellist are asked to rank the coded samples according

to there preference

Ranking testName………………… Date……………..Product………………….

• Please rank the samples in numerical order according to your preference or intensity of aroma/taste characteristic of the product.

Intensity/preference sample code 1 ______ 2 ______ 3 ______ 4 ______

Signature

• The panellist is asked to indicate the presence or absence and

intensity of a particular quality characteristic

• Analysis of two or more samples evaluated at different times

• By a different set of untrained panellists can be compared

2. Single sample test

Single sample testName………………… Date……………..Product………………….

• Please taste and rank the samples carefully. can you detect any off-flavour in the product? Circle one

Yes NOIf you detect any off-flavour Please it below. Intensity comments Trace off-flavour is due to- Moderate off-odour Strong off-taste residual taste other defects Signature

3. Two sample difference test This test is variation of the paired test and measure the amount of

difference

Each taster is served four pairs of samples

In two pairs duplicate samples. other two pairs test samples

To judge the independently difference between the test sample a standard on a scale ‘0’ representing no difference to ‘3’ representing extreme difference

The panellist is not guess and he is guessing through the coded duplicate standard in two pairs

Two sample difference testName………………… Date……………..Product………………….1.Compare the coded samples in each of the four pair given, test may or may not be different from

the reference sample.2.Determine the degree and direction scale Degree DirectionNo difference 0 Super to standard SVery slight difference 1 Equal to standard EModerate difference 2 Inferior to standard I Large difference 3 3.Comment on what the difference is based on;taste,odour or both.

sample Degree Direction Comment code no, difference _______ _______ _______ _______________ _______ _______ _______________ _______ _______ _______________ _______ _______ ________ Signature

4. Multiple sample difference test

• Each panellist is served 3-6 samples

• One sample is a known standard, panellist compares each

coded sample with the known standard

• One coded sample is a duplicate of the sample

• The panellist is not to guess. Direction and degree of

difference is also to be judged

Multiple sample difference test Name………………… Date……………..Product…………………. Taste it carefully for the quality characters to be evaluated to the reference sample for odour

and flavour. Rate in each sample degree of difference and the direction of quality. Degree of difference Direction of quality Rating Difference from standard 0 None E Equal 1 slight I Inferior 2 moderate S Superior 3 large

sample code no odour flavour Degree Direction comments Degree Direction comments

Signature

One of the method for studying the consumers’ acceptance of a

certain product is to determine how much they like it when

they are consuming

In 1940 the hedonic scale was developed at Quartermaster

Food and Container Institute of the US Armed Forces

In order to predict the acceptance of certain canteen food

products by soldiers

5. Hedonic Rating Test

Prepare the food samples

Ask each taster to taste each sample in turn and tick a

box, from '1 Dislike Very Much' to '5. Like Very Much‘ to

indicate their preference

This is a 5-point-scale Sometime a 9-point-scale is used

The taster may also wish to make remarks about the

products’ appearance, taste, odour and texture

Analyze the results. Which sample received the highest/lowest

scores? Which sample was preferred

Contd…

Name:………………… Date:……………..Product:………………….• Taste these samples and checking how much you like or dislike each one• Use the appropriate scale to show your attitude by checking at the point that

best describe your feelings about the sample. code code codeLike extremely ____ ____ ____ like very much ____ ____ ____ like moderately ____ ____ ____ like slightly ____ ____ ____ like or dislike ____ ____ ____Dislike slightly ____ ____ ____ Dislike very much ____ ____ ____Dislike moderately ____ ____ ____Dislike extremely ____ ____ ____Reason Signature

Hedonic Rating Test

6. Numerical Scoring test

• One or more samples are represented to each panelist

• Panelist evaluates each samples on a specific scale for a

particular characteristics indicating the rating of sample

• The panellists are trained to follow the sensory characteristics

corresponding to the agreed quality descriptions and scores

Numerical Scoring test

Name………………… Date……………..Product…………………. Please rate these samples according to the following descriptions

Sample Score Comment

Sample score comments

Signature

Score Quality description

90 Excellent

80 Good

70 Fair

60 Poor

7. Composite Scoring Test

• The rating scale is defined, so that specific characteristic of a

product are rated separately

• This method is helpful in grading products and comparison of

quality attributes by indicating which characteristic is fault in

a poor product

• It gives more information than the straight numerical method

Composite Scoring test

Name: …………………. Date:…………..Product: Orange Marmalade

Quality Possible score Sample scoresColour 20 ___ ___ ___ ___Consistency 20 ___ ___ ___ ___Flavour 40 ___ ___ ___ ___Absence of defects 20 ___ ___ ___ ___

CommentsSignature

Number of Panel members and samples required for sensory test

1. Ranking TrainedSemi-TrainedUn-Trained

5-1210-1572-80

2-7

2. Single sample TrainedUn-Trained

6-2572-80

1

3. Two sample difference Trained 6-25 4 pairs of Unknown and control sample

4. Hedonic Semi-Trained 10-25 5-10

5. Numerical scoring Un- TrainedTrained

72-805-12

1-41-6

6. Composite Trained 5-12 1-4

7. Multiple sample TrainedSemi-Trained

6-2510-15

3-6

Sl.No Method Panellists No. of sample tests

Conclusions

Even though affective studies are one of the most important

areas in the sensory evaluation field

Acceptance as well as preference tests present some challenges

that have led by researchers

These tests are not as simple as they may seem and results

should be carefully interpreted

Contd…….

• There are still several issues to be studied that are generating

future research studies in the area

• Alternative techniques are being developed to determine the

acceptance of certain products by consumers

• But their applicability still has to be analyzed and results

compared with the ones obtained using traditional tests

Thank you