Laboratory Exercises for Sensory Evaluation

From the co-author of Sensory Evaluation of Foods, Principles and Practices, this lab manual is a fitting accompaniment to that text in an undergraduate or graduate course in sensory evaluation of foods. The manual includes introductory information, such as report formats (both academic and industrial), as well as a series of eleven full-length lab exercises suitable for a three-hour laboratory period. There are also four shorter exercises suitable for a traditional class period, and one group exercise suitable for a semester project in descriptive analysis and terminology building. Correct use of graphs, tables and statistics is emphasized in several sections. Each exercise includes both a student section and one for instructors and teaching assistants, which features detailed instructions with supplies, equipment, preparation procedures, ballots and data sheets. Each instructor section also includes "keys to successful execution," which cover common mistakes and important details, designed to give the students the maximum opportunity for a rich learning experience. A group of statistical problem sets is included to reinforce common statistical analyses used with sensory data. Methods encountered include discrimination, descriptive, affective/hedonic, scaling, thresholds, panelist screening, shelf life and consumer questionnaires. Critical thinking and discussion questions are emphasized above and beyond the rote learning of a specific procedure. For classes that may be offered to less advanced students, suggestions are made in the instructor sections on how the exercise or report can be simplified. The exercises were compiled and refined over two decades and used in an upper level course in sensory testing at Cornell University.

Auteur

Harry T. Lawless is Professor Emeritus in the Department of Food Science, Cornell University.

Texte du rabat

Laboratory exercises are a necessary part of science education. They enable students to better understand the principles discussed in lectures, and provide them with hands-on experience of the practical aspects of scientific research. The purpose of this book is to provide students and instructors with a time-tested set of lab exercises that illustrate the common sensory tests and/or sensory principles used in evaluation of foods, beverages and consumer products. The appendices will also include a set of simple problem sets that can be used to teach and reinforce basic statistical tests. Approximately twenty years ago the Sensory Evaluation Division of the Institute of Food Technologists sponsored the preparation of a set of exercises titled "Guidelines for Laboratory Exercises for a Course in Sensory Evaluation of Foods," edited by one of the co-authors (Heymann). This book will provide additional materials from the second author (Lawless), as well as other instructors, in a uniform format that can be easily adopted for course use. Most importantly, the lab exercises will complement the flagship textbook in the field, Sensory Evaluation of Foods: Principles and Practices, 2E, also by Lawless and Heymann and published by Springer. Possible course adoption of the main text along with the lab manual should enhance the sales of these materials.

Contenu

Section A. Introductory Material and General Instructions.- 1. Introduction for Students.- 2. Introduction for Instructors and Teaching Assistants.- Section B. Eleven Laboratory Exercises in Sensory Evaluation.- 3. Screening panelists using simple sensory tests.- 4. Comparison of discrimination test methods.- 5. Forced choice thresholds using an ascending method of limits.- 6. Signal Detection Theory and the Effect of Criterion on Response.- 7. Sweetness of fructose and sucrose determined by different scaling methods.- 8. Time-intensity scaling.- 9. Flavor Profile Method.- 10. Introduction to Descriptive Analysis.- 11. Use of Reference Standard in Panel Training.- 12. Acceptance and Preference Testing.- 13. Optimization by ad libitum Mixing and the Just-About-Right Scale.- Section C: Brief Exercises and Group Projects.- 14. Group Exercise in Descriptive Analysis.- 15. Brief exercises.- Section D. Statistical Problem Sets for Sensory Evaluation.- Chapter 16: Sample Problem Sets for Statistics.- Exercise 1. Means, standard deviations, standard errors.- Exercise 2. Binomial-based statistics for discrimination tests.- Exercise 3: The t-tests.- Exercise 4. Simple Correlation.- Exercise 5. One and two-way ANOVA.- Exercise 6. Planned comparisons of means following ANOVA.- Exercise 7. Rank order tests.- Appendix. Sample data sets and open tables for calculations.