Question

In Sensory Evaluation, a Duo-Trio Test is classified as a _______.

• A. Descriptive test
• B. Affective test
• C. Difference test
• D. Threshold test

Hint:

Difference tests are also called discriminative tests.
The three most common difference tests are the Triangle test ($p = 1/3$), the Duo-Trio test ($p = 1/2$), and the Paired Comparison test ($p = 1/2$).

Answer 1

The Correct Option is C

Step 1: Understanding the Problem:
The question asks about the proper classification of the Duo-Trio test within the methods of sensory evaluation of foods.

Step 2: Key Concepts and Approach:
Sensory evaluation methods are divided into three major categories based on their objectives:
1. Difference (or Discriminative) tests, which determine if there is a detectable difference between samples.
2. Descriptive tests, which describe and quantify specific sensory attributes of a product.
3. Affective tests, which measure consumer preference, acceptance, or liking.

Step 3: Detailed Explanation:

• Definition of Duo-Trio Test: The Duo-Trio test is a specific discriminative method used to determine if an overall difference exists between two samples.

• Methodology: Panelists are presented with three samples simultaneously.
One sample is marked as a Reference (R), while the other two are coded with random three-digit numbers.
One of the coded samples is identical to the Reference, and the other is the test sample.
Panelists are asked to identify which of the coded samples matches the Reference.

• Statistical Basis: Since there are only two coded options, the probability of choosing the correct sample by chance is $50\%$ ($p = 0.5$).

• Usage: It is widely used in quality control to check if a change in ingredients, packaging, or processing has caused a perceptible difference in the final product.

Step 4: Final Answer:
Thus, the Duo-Trio test belongs to the category of Difference tests.