Standardization News Search

Magazines & Newsletters / ASTM Standardization News


March/April 2009

The Senses and the Science of Evaluation

New ASTM Manuals Guide Laboratory Setup and JAR Scale Use

The compilation of useful materials about sensory evaluation laboratories and just- about-right scales can be found in two new reference works by four members of ASTM International Committee E18 on Sensory Evaluation.

Manual 60 on Sensory Evaluation Labs

Along an interstate highway, billboards entice passersby to try the flavors — cheese, salt and vinegar, ketchup or hot hot hot — of a new snack food choice. Chances are that these munchies got put to the test, for flavor, crunchiness and more, in a sensory evaluation laboratory.

What that lab may possess in equipment and materials can be adapted for another lab, either a new facility or one to be remodeled, based on the information in ASTM International Manual 60, Physical Requirement Guidelines for Sensory Evaluation Laboratories: 2nd Edition.

The reference provides guidelines for planning and designing the lab site for food testing and other products, such as personal care items, pharmaceuticals and fabrics, to name a few, including the special considerations for each.

Editors Carla Kuesten, Kellogg’s, Battle Creek, Mich., and Lori Kruse, InsightsNow Inc., Corvallis, Ore., offer the three most important considerations for a successful lab setup:

  • Proper planning, including anticipated needs for the volume and type of testing expected or desired, respondent traffic flow, parking requirements, storage space, test preparation and serving areas;
  • Providing assistance and guidance to design and construction personnel in understanding facility needs that are important to sensory evaluation; and
  • Employing proper environmental conditions such as adequate space, lighting and ventilation for successful sensory testing.

To help visualize possibilities, example blueprints, drawings, photos and videos are linked on the CD-ROM and demonstrate what others have accomplished in their facilities.

Manual 63 on Just-About-Right Scales

A perhaps unlikely evaluator, Goldilocks arguably was a consumer product tester of porridge, chairs and mattresses — and foreshadowed responses used in today’s just-about-right scales. She certainly knew what she liked.

For today’s sensory evaluation professionals who systematically use these JAR scales in product testing, a new ASTM manual details how to go about it.

The work is Manual 63, Just-About-Right (JAR) Scales: Design, Usage, Benefits and Risks; it comprehensively covers this consumer testing approach, including how to create a JAR scale, use it, and analyze and interpret the results.

According to Editors Lori Rothman, Kraft Foods, Glenview, Ill., and Merry Jo Parker, Food Perspectives Inc., Plymouth, Minn., Manual 63 provides statistical case studies as well as the benefits and risk associated with JAR scales, plus alternatives. “This manual is the first practical guide on the use of just-about-right scales in consumer research, covering proper scale creation, analysis and interpretation,” Rothman and Parker note.

A JAR scale, typically used in conjunction with other acceptability scales to guide product development, balances descriptors of, for example, “not nearly shiny enough” or “not quite shiny enough” with “somewhat too shiny” or “much too shiny,” on either side of a midpoint of “just-about-right.” Researchers gather consumer responses to a product based on such a scale and then apply modeling and other methodology to the response data to reach statistical conclusions about a food or garment or other product.

And the manual provides context for the process and recommendations for customizing the scale and its use for individual purposes.