In this video you will learn how to set up and conduct sensory analysis
This is an example of a sensory analysis room
Because this is a food-safe environment, outside lab coats should not be worn in here
The food samples are prepared in the kitchen which is separated from the tasting area
This is the training area where panelists are calibrated in the way like machines would be
and they are taught how to precisely and accurately recognize certain characteristics when performing sensory analysis
These are the individual booths where panelists evaluate the foods
the booths come with normal lighting as well as red lighting to mask the differences in colour between samples
A typical tray setup for panelists include a napkin,
utensils if required,
a cup of water, some crackers for cleansing the palate,
food samples of equal volume in individual serving containers
and last but most importantly the sensory analysis questionnaire along with a pen
The serving containers should be labeled with random three-digit code
This is to keep the samples anonymous and prevent bias when panelist evaluate the samples
It's also important to ensure that all samples are the same temperature, or it may affect the sensory results from the panelists
To serve the panelists, server would bring trays from the kitchen to the booth by sliding the tray through the small door in the wall
There are three types of sensory analysis
Discriminative, descriptive and affective analysis
For the time point where each of the different sensory tests appear in the video,
please refer to the description box below
Discriminative tests are qualitative and they are used to determine whether panelists are able to tell the difference between samples
For example these tests are often used when performing quality control on a new batch of food
to ensure that this batch has no sensory differences from the control
In this video, we will demonstrate how to set up the following discriminative sensory analysis
which includes Triangle test, Paired Comparison test, and Duo-Trio test
Here is an example of how a triangle test is set up
Three samples will be used where two are the same and one is different
The questionnaire tells the panelists that two of the three samples are identical
and ask the panelists to identify the sample that is different
The order of tasting is also indicated on the questionnaire
A Duo-trio test is set up as follows
Three samples are again used
But this time one is used as a reference sample and the panelists must identify which of the remaining two coded samples
they believe is different compared to the reference
It's important to note that the quantity of the reference sample should be two times the amount of the code example
Here is an example of a Duo-trio test questionnaire
In a Paired Comparison test setup, only two coded samples are used
This test is unique compared to the previous two tests
because it allows the sample to be evaluated based on a specific characteristic
this is an example of what a pair comparison test questionnaire looks like
The Panelist is asked to taste the samples in the certain order and identify the one that fits more with the characteristic of interest
Descriptive Sensory tests are quantitative and they are used to determine how samples differ from each other based on specific criteria
The Descriptive Sensory analysis that will be explored in this video include line scale, category scale and ratio scale
Line scales are also known as unstructured scales
It's typically a horizontal 15-centimeter long line with anchor points 1.5 centimeter from each end
it also comes with an optional middle anchor point
A separate line skill is required for each attribute being tested
The anchor points are often accompanied by numbers and/or descriptive words
the panelists can indicate their score by marking a vertical line anywhere along the line scale
where it reflects their evaluation of the sample
The markings on the line scale can then be measured and translated into numbers for statistical analysis
Category scales are also known as structured scales
They range from 6 to 10 points with 7-point and 9-point scales being the most commonly used
This type of descriptive analysis allows one or more sample to be evaluated for a single or multiple attributes
here is an example of a category scale questionnaire
asking the panelists to evaluate three different jam samples for sweetness and to indicate the level of sweetness that best suits the sample
You can also use ratio scaling for sensory analysis
In this type of test, samples that are only different in one attribute are randomly assigned to panelists
and panelists are asked to rate the first sample and then rate the others in relation to the first one
Here is an example of a ratio scaling questionnaire
For example if the second sample is twice as sweet as the first one and you give the first sample a rating of two
Then the second sample should be given the rating of four which is twice the rating of the first sample
Affective tests, also known as hedonic tests,
are used to measure consumer preference, liking or acceptance of a product
We will discuss the most frequently used affective tests which include
Paired Comparison Preference, Hedonic Scaling and Ranking
The Paired Comparison Preference test is very similar to the Paired Comparison test in discriminative analysis
However instead of identifying the difference between two samples in a certain attribute
Paired Comparison Preference ask for Panelist preference between the samples
Here is an example questionnaire
The Hedonic scaling test is typically used to measure the degree of liking of a sample by consumers
this scale is very similar to the category scale as it includes a series of statements
which allows the panelists to express a varying degree of preference for the sample
The scale can be converted numerically and subsequently analyzed through statistical analysis
Here is an example of the questionnaire
The samples are in random three digit codes and presented in randomized order to the panelists
The ranking test is very similar to the Friedman ranking test in discriminative analysis
however instead of ranking the samples in a certain attribute
the ranking tests here ask the panelists to rank their preference of the samples
Here is an example of the questionnaire used
This concludes the three different types of sensory analysis. Thank you for watching