T.C.

UNIVERSITY OF GAZİANTEP

FACULTY OF ENGINEERING

DEPARTMENT OF FOOD ENGINEERING

    FE 376 FOOD QUALITY CONTROL LABORATORY 

Experiment Name:  “Sensory Analysis”

Submitted to: Asst.Prof.Dr. ÇİĞDEM ( AYKAÇ ) SOYSAL

Submitted by: Betül ÖZDEMİR

                          Başak Koç

                          Hüsamettin KİRAZ

                          Mustafa MUTLU

PURPOSE

The purpose of this experiment was application of triangle test for different kind of yogurt to find out a detectable difference between two similar yogurt.

THEORY

Sensory analysis (or sensory evaluation) is a scientific discipline that applies principles of experimental design and statistical analysis to the use of human senses (sight, smell, taste, touch and hearing )for the purposes of evaluating consumer products. The discipline requires panels of human assessors, on whom the products are tested, and recording the responses made by them. By applying statistical techniques to the results it is possible to make inferences and insights about the products under test. Most large consumer goods companies have departments dedicated to sensory analysis.

All sensory testing methods are divided into three categories: hedonistic, comparative and descriptive testing. Hedonistic tests are always used within the scope of consumer tests and serve to characterize consumer behavior. On the other hand, comparative and descriptive sensory tests are referred to as “expert tests” because they may only be carried out by trained persons and can give very detailed information about individual product parameters. Selection of a sensory testing method must always take into account the test objective.

The most common sensory testing method is triangle test. The triangle test is a discriminative method with many uses in sensory science including:

·         gauging if an overall difference is present between two products

·         selecting qualified panelists for a particular test

·         determining whether shifts in processing or ingredients have significantly changed a product.

During a triangle test, a panelist is presented with one different and two a like samples. If possible, all three samples should be presented to the panelist at once, and the panelist should be instructed to taste the samples from left to right. The six possible order combinations should be randomized across panelists. For samples A and B, the six possible order combinations are: AAB, ABA, BAA, BBA, BAB, and ABB. The panelist is instructed to identify the odd sample and record his answer.

DISCUSSION

      Sensory is an analytical method where the human senses are a sample of testers. Sensory analysis testing is used considerably in the food industry for product development. It also plays a key role in quality control and in the marketing of products.  Many types of sensory analysis tests have been devised to fulfil a number of specific objectives.  These tests are grouped into three categories. Preference test, Difference test, Descriptive test.

         Preference tests are used in the food industry to determine: if consumers like a product, if one product preferred over another and if consumers intend to use a product. Difference test are used to detect small differences in foods. Difference tests are used in food industry to answer some of the following questions: Does a difference exist? Would people notice the difference? How would you describe the difference? . Descriptive tests are used to describe the perceived sensory characteristics of products. Descriptive tests can be used in the food industry to answer some of the following questions: what does the product taste like? What are its perceived sensory characteristics / attributes? How does a change in processing / packaging / storage conditions affect the sensory quality of this product? And Triangle test; Tester is presented with three coded sample, two samples are the same, one is different, tester is required to identify the sample that is different.

We did triangle test in this experiment. A triangle test is a discriminative form of a sensory analysis. its results first’ Indicate whether or not a detectable difference exists between two samples.’ For this reason it is often used to ”in quality control to determine if a particular production run meets the quality control standard.”. To carry out the experiment the panelists must be provided with three coded samples of the products being tested. Two of the samples must be from the same product and panelists must pick the odd one out. The panelists must also be provided with another food or beverage to cleanse their palate and to minimize the cross contamination of different sample flavors in the mouth. In addition, there are nine possible errors which could influence a triangle test: · Expectation error: This error occurs when the panelists are given more than enough information about the test before actually doing it. Too many facts or hints cause panelists to make a judgment on expectation rather than intuition. For this reason it is important provide only the facts necessary to complete the test. 

            As a result this test (triangle test) is depends on the people. For this reason, we can taste different from the same sample. For example someone feels salty but someone feels spicy on the same sample. According to some people find strong acidic, some people find low acidic. For these result we should choose panelist very carefully.