This section defines the principal concepts and methods used in sensory analysis of brewery products. For individual flavour terms, see Method 13.12 Sensory Analysis: Flavour Terminology and Reference Standards.
The equipment and procedures described herein are designed to cover the requirements of brewery panel testing of beer, wort, water and other liquid products. The panel tasks considered in this method include not only difference testing, descriptive tests and quality control tasting, but also panel training, threshold testing, investigation of off-flavours, plant project tasting, and new product development. The text does not apply to consumer panels used for preference tests. This method was developed in collaboration with the International Organization for Standardization (8.1) and the American Society for Testing and Materials (8.2).
A guideline document to allow the selection of the most appropriate sensory method relevant to a given situation.
The procedures are suitable for establishing and maintaining a resident sensory panel to be used for difference tests, threshold tests and descriptive tests.
It is necessary to use EBC Methods 13.2, 13.7, 13.11 and 13.12
Use the procedures in this method to report the results of sensory tests on samples of beer, wort, water or other brewing materials or intermediate products, whether such reports are designed for publication or for internal use at the brewery. Internal reports can be shorter after a time to avoid repetition. The procedures described were developed (9.1) in collaboration with the Institute of Food Technology (9.3, 9.4), the International Organization for Standardization (9.5) and the American Society for Testing and Materials (9.6). Descriptors: average hop character, split plot ANOVA.
This test is used for the following purposes: 1. Directional Difference Test. To determine in what way a particular sensory characteristic differs between two samples, e.g. more sweet or less sweet. 2. Paired Preference Test. To establish whether a preference exists between 2 samples, e. g. in consumer tests. 3. Assessor training. To select train and perfect assessors. The Paired Comparison Test is one of the simplest and most used sensory tests. It is often used first to determine whether other, more complicated tests should be applied. Different methods of interpretation are used, depending on the test objective, and it is necessary from the outset to distinguish between two sided (bilateral) and one sided (unilateral) test situations. Descriptors: Directional Difference Test, Two sided Test, One sided Test, Level of significance.
It is necessary to use EBC Method 13.2
Use this test to determine either 1) whether the samples are significantly different or 2) whether the samples are significantly similar. The method is the same for testing for difference and similarity, but the statistical parameters selected for the evaluation of results and the minimum number of assessors required are different. Typically you need more assessors to test for similarity than to test for difference. Descriptors: score sheet, number of assessors needed for a triangle test, sample plan for a triangle test, number of assessments, risk of concluding that a significant difference exists when there is none,Maximum number of correct responses, number of panellists, significant difference.
It is necessary to use EBC Method 13.2
Use this test to determine whether a sensory difference is apparent between two samples (see “Note” Section 8). Descriptors: Triangular test, One-Side Test
It is necessary to use EBC Method 13.6
The test determines the lowest concentration of an added substance that can be detected by odour or taste. The threshold may be determined in order to: 1) Learn whether a substance present in beer is likely to exert an effect on flavour. 2) Provide an indication of the magnitude of any such effect by application of the concept of “Flavour Unit” (FU). For a given substance, the number of FUS present (or added) equals the concentration of substances present (or added) divided by the threshold (9.6). FU is also called “Odour Unit” when only the odour is considered. 3) Study the relative sensitivities of individuals to the test substance. 4) Select, train and perfect assessors. The test determines the Difference Threshold as defined by Brown et al (9.3). If the recognition threshold is required, assessors must describe and correctly identify the added flavour. Descriptors: presentation of the six triangles, Example of Questionnaire, Example of application.
Use this test with trained tasters to obtain a systematic description of the flavour of samples under test, for example, in the evaluation of test brews, or in quality control, or to train and perfect assessors. Descriptors: Series of government tank samples.
It is necessary to use EBC Methods 11.2, 11.4, 11.6, 11.11 and 11.12
Use this test to place a series of test samples (usually from 3 to 6) in rank order according to a given characteristic (criterion). The criterion may be the intensity of a single sensory attribute, or a group of related attributes, or a total impression. Descriptors: Specimen answer form, ranking test, test for bitterness, assessors, mean rank sum, number of assessments containing ties.
It is necessary to use EBC Methods 13.2, 13.4 and 13.6
This method describes an internationally accepted flavour terminology system for beer. It names and defines each of 122 separately identifiable flavour notes which can occur in beer. Approved flavour reference standards or procedures are provided for 27 terms and suggestions are given for 15 additional substances. Descriptors: Flavour Wheel, description of the terminology system, compounds recommended for use as flavour reference standards.
It is the duty of all employers to protect the health and safety of employees. To this end, all samples presented for sensory analysis and all materials used as standards to illustrate specific flavour notes must be fully assessed in order to ensure their safety and to comply with the relevant legislation in the country of use. It is strongly recommended that the following steps are taken.
A practical sensory analysis procedure for routine descriptive tests in brewery plants. This procedure is a guideline.
It is necessary to use EBC Methods 13.2, 13.4 and 13.5
Sensory analysis (including visual, smell and taste) of raw materials, processing aids and in-process samples to detect obvious defects or deviations at an early stage, resulting in an OK/not OK judgement. Descriptors: Guideline for routine sensory check.