Why do we crave chocolate? Why does a juicy, grilled steak taste better than one that's boiled? Why does the aroma of freshly baked bread make us feel comforted? The answer lies in sensory evaluation—the science of how we perceive and experience food through our senses.

In this blog post, we’ll explore what sensory evaluation is, the senses involved in tasting food, and how scientists and food producers use this knowledge to improve the way we eat and enjoy food.

What Is Sensory Evaluation?

Sensory evaluation is the scientific discipline that measures, analyzes, and interprets the way people perceive food through the five senses: sight, smell, taste, touch, and hearing.

It’s a critical part of food science, used to:

  • Develop new food products

  • Improve recipes or formulations

  • Ensure consistency in quality

  • Understand consumer preferences

  • Evaluate shelf life and storage effects

The Five Senses of Food

1. Sight

Our eyes are the first tools we use to judge food. Visual appearance influences expectations about flavor, quality, and freshness.

  • Color: Affects our perception of ripeness and flavor (e.g., red apples seem sweeter)

  • Shape and size: Uniformity is often linked with quality

  • Texture: Glossiness or dullness can indicate freshness

2. Smell (Olfaction)

Smell contributes up to 80% of what we perceive as taste. Aromas come from volatile compounds released by food.

  • Orthonasal smell: Sniffing food before it’s eaten

  • Retronasal smell: Aroma perceived from the back of the throat during chewing

Think about the smell of coffee, grilled meat, or fresh herbs—it primes your brain for what's to come.

3. Taste

Taste happens when molecules stimulate taste receptors on the tongue. The five basic tastes are:

  • Sweet – usually signals energy-rich foods (sugar, honey)

  • Sour – comes from acids (lemon juice, yogurt)

  • Salty – essential for electrolyte balance (salt, cheese)

  • Bitter – often a warning of toxins (coffee, dark greens)

  • Umami – savory or meaty taste (soy sauce, tomatoes, parmesan)

Taste is strongly influenced by smell, temperature, and even expectation.

4. Touch (Mouthfeel)

Mouthfeel refers to the physical sensations experienced while chewing or swallowing food.

  • Crispy, crunchy, creamy, chewy, smooth, gritty, etc.

  • Temperature and texture matter—a warm, gooey brownie feels different from a cold one.

5. Hearing

Sound affects our perception too—especially with crispy or carbonated foods.

  • The crack of a chip, the pop of soda bubbles, or the sizzle of a steak on the grill all enhance our eating experience.

Types of Sensory Evaluation Tests

There are several types of sensory tests used in food science:

1. Discrimination Tests

These ask if people can tell the difference between products.

  • Example: Triangle test – which one is different?

2. Descriptive Analysis

Trained panels describe the sensory characteristics in detail.

  • Example: A wine tasting panel evaluating aroma notes, acidity, and finish

3. Hedonic (Preference) Tests

Untrained consumers rate how much they like a product.

  • Example: “On a scale of 1 to 9, how much do you like this yogurt?”

Why Sensory Evaluation Matters

✔️ Product Development – Ensures new foods meet consumer expectations
✔️ Quality Control – Detects off-flavors, texture changes, or appearance issues
✔️ Marketing Insights – Reveals what flavors and textures people love
✔️ Health and Nutrition – Helps design low-sugar or low-salt products that still taste good

For example, if a company reduces the fat in their cookies, sensory evaluation ensures the new version still delivers a satisfying crunch and flavor.

The Human Element

Even though chemistry and machinery play huge roles in food production, humans remain the final judge of whether food is acceptable. Sensory scientists must consider psychological and cultural factors, too.

  • Expectations: If something looks like strawberry but tastes like cherry, people may dislike it.

  • Context: A food enjoyed at a picnic might not be as appealing in a lab setting.

  • Memory: Past experiences shape how we react to smells and flavors.

Conclusion

Sensory evaluation is both a science and an art—it bridges the gap between food chemistry and human experience. It helps us understand why we love certain foods and how to design better ones in the future.

Next time you savor a favorite meal, take a moment to notice how your senses are at work. From the aroma to the texture to the sound of a satisfying crunch—it's all part of the complex and wonderful way we enjoy food.