344 Chilled foods its quality. The pastry tends to adsorb moistness from the other ents to become soggy prior to any development of off-flavour 12.3 Sensory evaluation techniques From the previous section, it is obvious that any test to measure quality of chilled food should involve the use of human subjects Sensory evaluation is a scientific discipline involved with the measure study and interpretation of responses to food properties as perceived by the senses of sight, smell, taste, touch and hearing(IFT 1975) ensory assessment is done either by a small pool of people( typically 8 to 30 people)who have received some training, known asobjective testing or by a larger pool of consumers who give their own opinion on a product or range of products without any prior training. This is known as'subjective testing. The objective and hypotheses defined in any project brief will determine the choice of the type of valuation to be performed, and the type of panel, the test and the overall design of the experiment. Carpenter et al.(2000) defines in detail the criteria to consider Objective testing is carried out by qualified and trained people and can be used for discriminating and describing differences between chilled products This pool of people, or sensory panel, can be employees of a company or a dedicated workforce. After initial recruitment to measure any sensory impairment such as anosmia (impairment in the sense of smell) or ageusia (impairment in the sense of taste), the panel members take part in an extensive and gradually more difficult training schedule in order to describe, discriminate and evaluate any subtle differences between the products under investigation Many sensory professionals have published training schedules for general aining sessions Jellinek 1985) to more specific and precise sensory programmes( Civille and Szczesniak 1975). Tests used to characterise food properties by sensory experts can be either discriminative or descriptive 12.3.1 Discriminative tests These types of tests are used when it is required to identify if any difference exists between two or more products. It might be required to change an ingredient supplier for cost reduction or quality reasons and the brief is to confirm that the overall flavour, texture or appearance is not affected. It is more cost effective to ask a highly trained panel of experts in their field to assess any difference rather than asking consumers. The tests are very sensitive to any direct most commonly used discriminative test. In this test, panellists are given three mples, in a pre-determined order, one is different from the other two. They are asked to identify the odd sample(BS 5929: part 5, 1988). For example, a ham manufacturer might want to assess the effectiveness of a controlled atmosphere packaging against a present system without changing the overall sensorypredicts its quality. The pastry tends to adsorb moistness from the other components to become soggy prior to any development of off-flavour. 12.3 Sensory evaluation techniques From the previous section, it is obvious that any test to measure quality of chilled food should involve the use of human subjects. Sensory evaluation is a scientific discipline involved with the measure, study and interpretation of responses to food properties as perceived by the senses of sight, smell, taste, touch and hearing (IFT 1975). Sensory assessment is done either by a small pool of people (typically 8 to 30 people) who have received some training, known as ‘objective testing’ or by a larger pool of consumers who give their own opinion on a product or range of products without any prior training. This is known as ‘subjective testing’. The objective and hypotheses defined in any project brief will determine the choice of the type of evaluation to be performed, and the type of panel, the test and the overall design of the experiment. Carpenter et al. (2000) defines in detail the criteria to consider. Objective testing is carried out by qualified and trained people and can be used for discriminating and describing differences between chilled products. This pool of people, or sensory panel, can be employees of a company or a dedicated workforce. After initial recruitment to measure any sensory impairment such as anosmia (impairment in the sense of smell) or ageusia (impairment in the sense of taste), the panel members take part in an extensive and gradually more difficult training schedule in order to describe, discriminate and evaluate any subtle differences between the products under investigation. Many sensory professionals have published training schedules for general training sessions (Jellinek 1985) to more specific and precise sensory programmes (Civille and Szczesniak 1975). Tests used to characterise food properties by sensory experts can be either discriminative or descriptive. 12.3.1 Discriminative tests These types of tests are used when it is required to identify if any difference exists between two or more products. It might be required to change an ingredient supplier for cost reduction or quality reasons and the brief is to confirm that the overall flavour, texture or appearance is not affected. It is more cost effective to ask a highly trained panel of experts in their field to assess any difference rather than asking consumers. The tests are very sensitive to any sensory variation as they involve a direct comparison. The triangle test is the most commonly used discriminative test. In this test, panellists are given three samples, in a pre-determined order, one is different from the other two. They are asked to identify the odd sample (BS 5929: part 5, 1988). For example, a ham manufacturer might want to assess the effectiveness of a controlled atmosphere packaging against a present system without changing the overall sensory 344 Chilled foods