Food Selection & Sensory Evaluation 1

Sensory Attributes of Food

• Primary Taste Modalities:

  • Sour

  • Umami

  • Salty

  • Sweet

  • Bitter

Learning Objectives

• Understand the effect and importance of sensory attributes on food selection.

• Explain the physiology of the sensory experience.

• Explore the concept of a supertaster.

• Describe the food industry's approach to sensory questions.

Food Selection Criteria

• Main Criteria:

  • Sensory Impressions:

    • Sight: Food presentation.

    • Odor: Aroma evaluation.

    • Taste: Includes five basic taste stimuli.

    • Sound: Texture-related sounds, e.g., crunchiness of melon.

    • Touch: Mouthfeel sensations.

The Senses in Food Evaluation

• Sensory Properties:

  • Color: Affects perceptions of ripeness and sweetness.

  • Texture & Consistency: Influence on eating experience.

  • Volatile Flavor Substances: Contributes to flavor profile.

• Taste Sensations:

  • Sweet, Sour, Bitter, Salty, Umami

Aroma and Odor

• Importance of Aroma:

  • Evaluates food quality and desirability.

  • Requires volatilization of molecules.

  • Odor triggers linked with memory due to olfactory connections in the brain.

Human Physiology in Food Selection

• Olfactory Pathways:

  • Olfactory epithelium signals aromas to the brain.

  • Interplay between taste and aroma during swallowing.

Detection of Odor

• Odor detection is highly sensitive, even at low concentrations.

• Adaptation occurs with prolonged exposure, diminishing detection ability.

• Approximately 95% of taste experience is derived from odor.

Taste and Its Physiology

• Basic Taste Definitions:

  • Saltiness: From sodium ions (Na+).

  • Sourness: From hydrogen ions (H+).

  • Sweetness: From sugars, glycols, and certain alcohols.

  • Bitterness: Associated with alkaloids and some phenolic compounds.

  • Umami: Derived from glutamate; described as meaty or savory.

  • Oleogustus: Recently recognized taste for certain fats.

Kokumi

• Definition:

  • Flavor modifier isolated from garlic.

  • Enhances mouthfulness and thickness but is not classified as a sixth taste.

Taste Buds Structure

• Anatomy of Taste Buds:

  • Composed of various papillae types: Circumvallate, Foliate, and Fungiform.

  • Each taste bud contains 50-100 taste cells with microvilli necessary for taste sensation.

Factors Influencing Taste

• Age, genetics, memories, food temperature, and variety/pattern of food consumed affect taste sensitivity and preferences.

Inherited Taste

• Example: "Broccoli dilemma" related to TASR38 gene influence on food preferences.

Supertaster Research

• Demographics:

  • More prevalent in certain ethnic groups; linked to heightened sensitivity to bitter and sweet sensations.

  • Correlation with dietary choices and potential health effects, such as colon cancer risk.

Sensory Evaluation of Food

• Objective:

  • Assess palatability and consumer acceptability through subjective tests (panel taste tests).

• Types of Sensory Tests:

  • Subjective Tests: Identify preferences.

  • Analytical Tests: Detect differences in samples.

Examples of Sensory Testing Methods

• Discriminative Tests: Identify discernible differences between samples.

• Affective Tests: Focus on consumer preferences and enjoyment.

• Descriptive Tests: Quantify differences in flavors or textures.

Environmental Sensory Components

• Sound: Related to quality evaluation and texture perception.

• Touch/Mouthfeel: Influenced by temperature, thickness, and overall consistency.

Objective Evaluation Techniques

• Laboratory Instruments Used:

  • Microscope, Spectrophotometer, Penetrometer for texture, and Viscosity measurements.

  • Electronic Nose: Detects gas presence related to aroma.

Conclusion

Understanding sensory evaluation and the physiological aspects of taste is crucial for food selection, consumer preferences, and improving food products within the food industry.