Chapter 2 Food Evaluation

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Understanding Food Principles and Preparation • Fifth Edition
AMY BROWN
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Food Evaluation
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• Two types of food evaluation
– Sensory (subjective) tests
– Objective tests
Food Evaluation

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• Testing foods involves our perception of
the food (sight, taste, odor, etc.)
• Two main types
– Analytical (effective) tests
– Affective tests
Sensory (Subjective) Evaluation

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Sensory Evaluation (cont’d.)

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• Analytical (effective) tests
– Detects discernible differences
– More objective than affective tests
– Usually conducted by a trained panel
• Discriminative tests
– Are the products different?
• Descriptive tests
– How are the products different?
Sensory Evaluation (cont’d.)

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• Affective tests
– Detects preferences
– Participants asked to rank products or state
whether they like a product or not
– Usually given to untrained consumers
• Hedonic tests
– How much do you like the product?
• Preference tests
– Which product do you prefer?
Sensory Evaluation (cont’d.)

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• Elements of sensory evaluation
– Taste panels
• Usually at least five people
• Mixture of gender, age, etc.
– Sample preparation
• Same size samples; same part of food, etc.
Sensory Evaluation (cont’d.)

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• Physical and chemical evaluation
• Performed with laboratory equipment, not
humans
• Analyzes content and safety of food
Objective Evaluation

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• Physical tests
– Size and shape
– Weight
– Volume
– Density
– Moisture
– Texture
– Viscosity
Objective Evaluation (cont’d.)

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Objective Evaluation (cont’d.)

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Objective Evaluation (cont’d.)

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Objective Evaluation (cont’d.)

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Objective Evaluation (cont’d.)

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• Chemical tests
– In-house vs. food testing laboratories
– Testing influenced by real-world situations
(i.e., melamine testing)
– Electronic noses
• Detect certain chemicals responsible for aroma
Objective Evaluation (cont’d.)

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Objective Evaluation (cont’d.)

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• Both are important for food evaluation!
• Sensory evaluation
– More expensive and time-consuming
– Vital for product research and development
• Objective evaluation
– More reliable and repeatable
– Not subject to human opinion
– Good for routine quality control
Sensory vs. Objective Evaluation

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• Sensory evaluation
– Analytical tests
– Affective tests
• Objective evaluation
– Physical tests
– Chemical tests
Chapter Summary