This document discusses methods for evaluating food, including sensory/subjective tests involving human perception and objective tests using laboratory equipment. Sensory evaluation includes analytical tests to detect differences between foods and affective tests to assess preferences. Objective evaluation analyzes physical characteristics like texture, weight and chemical composition. Both sensory and objective evaluation are important, with sensory vital for product development and objective tests providing reliable quality control.

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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