(QC/SENSORY)

Question 1

In the twentieth century, attention was given to
the selection and training of quality assessors
to utilize of formal sensory methods including:

Answer 1

• Use of reference standards.
• Use of formal data analysis methods to
  summarize and interpret the quality data.

Question 2

Over time, QC/sensory evolved in two important paths:

Answer 2

a) Focused on the challenges of initiating and maintaining a QC/sensory program in an organization.

b) Focused on sensory methods that were practical and effective for an in-plant QC function.

Question 3

• Method used for QC/sensory function:

Answer 3

o Attribute descriptive method
o Different from control method
o In-out method

Question 4

ATTRIBUTE DESCRIPTIVE METHOD

Answer 4

Focus on a small number of sensory attributes that have been
demonstrated to impact consumer acceptance.

Question 5

ATTRIBUTE DESCRIPTIVE METHOD-sensory specifications are based on

Answer 5

consumer acceptance and the attributes descriptive methods are typically applied only to finished products.

Question 6

Objective of Attribute descriptive method is to provide detailed information on :

Answer 6

Ø What is varying perceptibly/ detectable in the product?
Ø The magnitude of the variability.
Ø The direction of variability relative to the product’s sensory specifications.

Question 7

Major drawback of attribute descriptive methods:

Answer 7

Ø High level of resources.
Ø Need significant resources to identify the sensory attributes.
Ø Involve parallel descriptive and consumer evaluations of many production samples.
Ø Requires QC program maintenance

Question 8

Implementing an attribute descriptive QC
program:

Answer 8

1. Establish sensory specifications
   * Initial sample screening
   * Sensory descriptive evaluation and sample selection for consumer testing
   * Consumer testing production samples
   * Establishing the sensory specifications
2. Implementing the in-plant QC/sensory function
3. Product sampling, data analysis and reporting

Question 9

Objective Establishing sensory specifications

Answer 9

To develop a set of relevant sensory specifications.

Question 10

Establishing sensory specifications Involve 2 steps:

Answer 10

1. Identification of a small number of sensory attributes (5-15) that influence the consumer’s acceptability of the product.
2. Establish of ranges of intensities for each of these attributes (using 15-unit scale).

Question 11

Initial sample screening

Answer 11

Collection and screening of many production samples.

Question 12

Number of units of production that need to be collected at this stage must be adequate for

Answer 12

subsequent formal sensory descriptive evaluations and consumer testing

Question 13

Things to be considered:

Answer 13

• Logistical issue
• Space available to store the sample
• How quick the sample can be evaluated
• Shelf-life issue

Question 14

b. Sensory Descriptive Evaluations and Sample Selection for Consumer Testing

Answer 14

• To obtain a comprehensive description of all the sensory properties of each sample and to fully characterize the ranges of
  variability.

Question 15

Sensory Descriptive Evaluations and Sample Selection for Consumer Testing- goal:

Answer 15

to identify the smallest number of samples
that fully represent the total sensory variability of the product.

Question 16

Familiarity with the product and sound sensory judgment should
be used in combination with

Answer 16

the statistical results to decide
which attributes should remain.

Question 17

Consumer testing production samples

Answer 17

The questionnaire for the consumer test can be relatively short, consisting of acceptability questions- overall (aroma, appearance, texture, flavor etc.) and of specific attribute intensity questions.

Question 18

• The key consumer acceptance measures will be combined with
  the sensory descriptive ratings of the test samples to

Answer 18

o identify the
attributes that affect consumer acceptance

Question 19

Establishing the sensory specifications

Answer 19

The relationship between consumer acceptance and the intensities of the sensory attributes lead to the sensory specifications for the product.

Question 20

Correlation analysis can be used to

Answer 20

identify attributes that have a strong straight-line relationship with acceptance

Question 21

Three key patterns are likely to emerge
on the charts:

Answer 21

1. There may be no systematic relationship between acceptance and the intensity of the sensory attribute
2. There may be a strong linear trend , either increasing or decreasing
3. There may be a strong curvilinear trend where intermediate intensities of the attribute have higher acceptability than extreme.

Question 22

No systematic relationship between acceptability and the intensity of an attribute means

Answer 22

no sensory specification is needed
for that attribute.

Question 23

• Linear relationships with acceptability, one side specification apply.

Answer 23

Lower specification limits are set for
attributes with increasing trends; upper specification limits are set for attributes with decreasing trends

Question 24

Curvilinear relationships with acceptance,

Answer 24

both lower and upper specification limits may be needed.

Question 25

Develop the in-plant resources that will be used to

Answer 25

monitor the sensory quality of the products

Question 26

how to develop the resources

Answer 26

i. Identify an in-plant sensory coordinator who will oversee the operation of the in-plant QC/ sensory panel and coordinate with the other QC functions to communicate the results of the panel’s evaluation.
ii. Candidates for QC/sensory assessors need to be identified, screened, trained and put to work.

Question 27

QC/ sensory assessors can be drawn from

Answer 27

company employees or from non-employees who are willing to work part time as a panel.

Question 28

Once a pool of assessors is identified, the QC/sensory panel

Answer 28

screening and training on the attributes that will be evaluated as part of the QC/sensory evaluation and to be calibrated to the
intensity scales that will be used

Question 29

Step 3: Product sampling, data analysis and
reporting

Answer 29

For each attribute, the panel’s average intensity rating is
calculated for each sample collecte

Question 30

The most common QC summary measures are

Answer 30

the sample
mean and the sample range