Joel L. Sidel

6 – Descriptive Analysis

Publisher Summary This chapter deals with the descriptive analysis, which is the most sophisticated concept in the sensory analysis of products. Descriptive methods were designed to analyze products with a high degree of reliability and precision. Results from a descriptive analysis test provide complete sensory descriptions of an array of products, the basis for mapping product similarities and differences, and a basis for determining sensory attributes. The chapter classifies six test methods for descriptive analysis, according to whether the results are qualitative or quantitative. The test methods described in the chapter are: flavor profile, texture profile, quantitative descriptive analysis (QDA method), spectrum descriptive analysis, free-choice profiling, and diagnostic descriptive analysis. The development of the methodology has been traced from the use of a product expert through the more formal and rigorous approach applied in the QDA method. The QDA methodology emphasizes on the behavioral basis of the judgment process and combines with a rigorous approach to assess response reliability.

The role of sensory evaluation in the food industry

Abstract Increased competition and new opportunities stimulated by progressively vanishing trade barriers and expanding world markets, have greatly accelerated the food industrys world-wide requirement for new products, quality improvements, extended shelf-life, increased productivity, and lower production and distribution costs. Success within the framework of these new challenges will be directly related to the industrys ability to develop more precise knowledge about consumer attitudes and perceptions related to food products, and how these are best measured and implemented. Sensory evaluation is a critical component to that process. Historically, sensory evaluation has often been associated with product experts, and later as a more passive member of the product development team. Currently, the new challenges facing the food industry are progressively transforming sensory to a more proactive role, responsible for generating new product ideas based on unique sensory properties or unique consumer segments identified only through sensory behavior. However, the survival of sensory evaluation as an independent information resource is not guaranteed. Sensory evaluation must develop and improve its methods and more clearly delineate its responsibilities and role in the food industry. This paper focuses on the new and changing role for sensory evaluation in the food industry.

Introduction to Sensory Evaluation

Sensory evaluation is a scientific discipline that is used to measure, analyze, evoke, and interpret the reactions to those characteristics of foods and materials as they are perceived by the senses of sight, smell, taste, touch, and hearing. Sensory evaluation involves the measurement and evaluation of the sensory properties of foods and other materials. Sensory evaluation also involves the analysis and the interpretation of the responses by the sensory professionals. Linking of sensory testing with other business functions is essential, because it is essential for the sensory professional to understand the marketing strategy. Sensory evaluation principles have their origin in physiology and psychology. The information derived from experiments with the senses has a major influence on test procedures and on the measurement of human responses to stimuli. Sensory information is used as a part of marketing decision to identify and quantitatively model the key drivers for a products acceptance, and is now generally recognized as a core resource for any sensory program.

7 – Affective Testing

Publisher Summary This chapter discusses a sensory evaluation model for measuring product acceptance. Sensory acceptance represents the third and final phase of test resources along with discrimination and descriptive analysis tests. As a resource, it provides continuity between the controlled laboratory environment and the typical product use situation, such as home, restaurant, and so forth. The types of sensory acceptance tests include the laboratory, central location, and home-use. All of these test types follow accepted sensory evaluation procedures and practices. The sensory acceptance test is a very cost-effective resource and plays a major role in the development of successful products. The chapter discusses two methods to measure preference and acceptance—the paired-comparison test and the nine-point hedonic scale. The subjects participating in a sensory acceptance test should be qualified based on typical demographic and usage criteria or preference scores from survey data. The chapter also discusses the relationship between the sensory acceptance and the larger-scale marketing research models, and the role of the sensory acceptance model and its responsibilities in the product evaluation.

Test Strategy and the Design of Experiments

Publisher Summary This chapter focuses on test strategy in relation to experimental design, taking into account the request for assistance, product criteria, and the impact of psychological errors on response behavior. Experimental design is also considered with a sensory orientation. The chapter focuses on test strategy as it is applied to the individual request for assistance. The overall goal is to formulate and implement a test plan that will satisfy the stated objective. Specific issues that need to be considered before a plan is completed, and the test implemented are in addition to test priority, objective, and product identification and availability. Test strategy should include the possibility of an initial rejection of a request if the products are inappropriate or the basis for the request cannot be justified. Sensory evaluation uses statistics to determine whether the responses from a group of subjects are sufficiently similar or represent a random occurrence. The chapter also discusses the statistical issues that sensory professionals consider while determining the most appropriate experimental design and analysis for a particular problem.

The Organization and Operation of a Sensory Evaluation Program

Publisher Summary This chapter discusses the organization and operation of a sensory evaluation program. It identifies and characterizes the individual elements that make up a sensory evaluation department in a company. Organizing sensory activities begins with a plan to develop managements awareness of the value of sensory information. The initial step in this process is to develop a written plan, reflecting what has been done, what is being done now and what could be done in the future. Numerous activities were identified, including management-approved goals and objectives, professional staff, program strategy, facilities, test methods, identification, screening and selection of subjects, subject performance monitoring, test requests and reports, data processing, operations manual as well as planning and research. The first step in the process, after identifying the need for sensory resources, is to establish a dialog with management and with potential test requestors that identifies the benefit of sensory program. Matching this expressed need with available resources enables sensory evaluation to develop a realistic plan for the company. This chapter emphasizes on the need for a formal approach to the development of sensory resources to develop a pool of qualified subjects, use procedures that are scientifically sound, document requests and reports, maintain subject performance records, and establish direct lines of communications with technologists and brand managers.

Sensory Science and Consumer Behavior

Publisher Summary This chapter highlights the consumers behavior and also mentions the sensory approach for product testing. Consumers can readily express their preferences and respond to statements about a products image, package, and so on. However, when asked to explain the basis for their choice, consumers often repeat advertising information and/or make statements they think the researcher wants to hear. For example, when asked about the vanilla in vanilla ice cream, invariably the responses indicate more vanilla flavor is needed. But when more is added, the same response occurs as if there were no change. With continued additions of as much as 40–50%, the acceptance decreases dramatically. The importance of connecting a product with consumer expectations based on the imagery can be conveyed through advertising in addition to other more typical kinds of product information. The challenge has been to create a test situation/protocol in which all these product-related information sources can be incorporated into a testing environment. The sensory measures are obtained from a trained descriptive analysis panel, and the preference and other attitudinal information is obtained from qualified consumers. This approach provides a more in-depth understanding of how attitudes and perceptions interact, and this, in turn, leads to a better knowledge of which product formulations are most likely to succeed. In situations where product changes are warranted, it provides a road map for those changes.

Preface, Third Edition

When the second edition of this book was nearly exhausted, and orders were grinding to a halt, Springer urged me to do a third edition. At the age of 90 I said that was out of the question, but perhaps a co-author could be found. I spoke to several distinguished demographers, and the general drift of their replies was that the book was complete and well-rounded (my own opinion!) and there was nothing that could be usefully added. We were monumentally wrong. We hadn’t noticed the world of whales and birds and land animals, i.e., the world of biology. Hal Caswell has drastically broadened the perspective. Just as Alfred Lotka went far beyond the human species, so does Caswell. That wider perspective is fully incorporated in this third edition. It should not only be of interest to demographers, but to scholars of wide areas of biology. I can’t thank Joel Cohen enough for realizing this and putting me on to Hal Caswell. His work on the third edition makes it a very different and much better book. Without Caswell, the book would have died with the second edition.

8 – Special Problems

Publisher Summary This chapter draws attention toward some applications for sensory resources, particularly to those applications in which sensory information is not the only information source, yet it is often crucial to the decision-making process. While these activities will bring attention to sensory evaluation, they require a much greater understanding. Sensory professionals cannot expect to be focusing their attention solely on a test, rather as much attention must be given to the basis for a problem, what are the objectives, who will make decisions, and how will they be made, and so forth. Therefore, sensory professionals must make the transition from servicing requests to a direct involvement in the organization and planning process. In describing specific problems, this chapter and emphasizes the planning and organizational aspects of the particular problems and identifies the ways in which sensory evaluation can contribute. The chapter concludes that principles of sensory evaluation do not change, only their applications change. Success depends on the patience, skills, and the knowledge of the sensory professional.