8.2 Basic Considerations for Selecting Objective Sensory Analysts

Sensory evaluation encompasses the sciences of psychology, anatomy, physiology, and psychophysics.  Psychology is as important as the sciences when training people. Certain personality factors are critical for successfully conducting sensory activities. The personality traits listed below are outlined in the ISO; Technical Committee 34 for Sensory Evaluation document General Guidance for the Recruitment and Training of Panel Leaders; the book, Sensory Evaluation Techniques; and the manual, from Sensory Spectrum's course on panel leadership.

• Good communicator,
• Nurturing,
• Non-threatening,
• Sensitive.

B. Ability to Recognize Basic Tastes

Sensory analysts should demonstrate that they have the ability to perceive basic odors and tastes and be able to describe their findings in a consistent manner. One area that is important in  selection and training is the ability of the analyst to distinguish between the four basic tastes which are bitter, sour, salt, and sweet.

Taste Exercise

Purpose:  To demonstrate basic taste sensations to candidates for later testing purposes.

Equipment Needed:

• One gallon spring/filtered water.
• Four 500 mL graduated glass or Nalgene flasks with covers.
• Four 2-ounce plastic cups with lids for each participant.
• Cups for rinsing and spitting.
• Gram scale.
• Compounds [sucrose (sugar), citric acid, NaCl (salt), and caffeine].
• Ballots (see 8.6 Appendix: Sensory Scale).

Exercise Set-Up:

• Prepare the four basic taste solutions one or two days prior to screening. 
• Add compound to flask, then fill to 400 mL with filtered water.
  1. Sweet: 20.0 g sucrose.
  2. Sour: 0.2 g  citric acid.
  3. Salty: 1.4 g  NaCl.
  4. Bitter: 0.2 g caffeine.
• Store bulk solution in cooler/refrigerator.
• Label the side of the cups with the number associated with solution, 1 each per participant: 1= sucrose, 2 = citric acid, 3 = NaCl, and 4 = caffeine.
• Let compound sit over night and shake to dissolve.  Fill the 2 oz. cups half full and cover.  The analyst should have enough solution to make up 15 to 20 cups.
• Make sure solutions are at room temperature when presented.

Screening Exercise:

• Remove cups from cooler one to two hours prior to screening.  It is important that the solutions be evaluated at room temperature.
• Present the four basic tastes.
• Pass out ballots and read instructions to participants.
• Have them go through the samples in order and ask them to pay attention to where they are sensing the solutions on their tongue and how long it takes to detect.  Ask them to save some for re-tasting.