Descriptive tests

Food Standard and Quality Control

Lesson 12 : Subjective Methods

Descriptive tests

Descriptive testing is used to identify and provide a picture or “profile” of the important sensory characteristics of a product. With sensory profiling more than two samples can be assessed simultaneously. This type of test has the advantage of not only being able to tell you whether or not there is a difference between samples but also the nature and magnitude of these differences. Appearance, odour, flavour and texture can all be assessed in this way and the characteristics can be quantified using various techniques and scales as outlined in this section.

  1. Hedonic scale:

    Hedonic rating relates to degree of acceptance of a product parameter or parameters on a given scale. The hedonic rating test is used to measure 'the consumer acceptability of food products. Samples ranging from one to four are served to the panelist in a single session. He will be ­asked to rate the acceptability of the product on a scale, usually of 9 points, ranging from 'like extremely' to dislike extremely'. Scales with different ranges such as 1 to 5 where 1 not acceptable and 5 is highly acceptable and other experience phrases such as very hard or crunchy could also be used.

    When pronounced after-effects are met with, precluding testing of a sec­ond sample or when independent judgments are sought for, separate cards are used for each product. When relative preference is the object of study, cards with multiple columns for the number of test samples are used.

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  3. Rank preference test:

    This test is· used to differentiate several samples on the basis of a single characteristic, such as Flavor, texture, or overall acceptability. Panellists are presented all samples simultaneously (including a standard or control if used) with code numbers and are asked to rank all samples according to the preference of the samples ie ., most preferred sample is ranked first..

  4. g

  5. Paired Preference test:

    A paired preference test is a simple task for respondents, and can be used with populations that have minimal reading or comprehension skills, or both. Preference is not an intrinsic attribute of the product, such as hue is, but is a subjective measure relating to respondents' affective or hedonic response. It differs from paired comparison testing which measures objective characteristics of the product. Preference results are always dependent on the population sampled.

    This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

Ballot for tomato puree paired-preference test

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Last modified: Friday, 17 February 2012, 9:27 AM