Food Quality

1. Food Quality • Sensory attributes • Nutritive content • Food safety

2. Sensory Evaluation • Human senses to evaluate palatability • “humans” as panelist or judges as measurement instrument • Value depends on objectivity & precision of judgments

3. Primary sensory attributes • Appearance • Flavor • Texture • Perceived by senses individually and processed by brain into total impression of quality

4. Appearance • Shape & size • Color or hue • Gloss/luster/sheen & other surface characteristics • Volume • Interior appearance

5. Factors Affecting the Perception of Appearance • Nature of the light source • Nature of the object • Nature of the surroundings

6. Texture: chemical & physical • Hardness/tenderness • Brittleness • Chewiness • gumminess • Cohesiveness • Viscosity • Elasticity • Adhesiveness

7. Flavor • Olfactory (smell) • Nose • Nasal cavity from mouth • Taste • Salt (front sides) • Bitter (back) • Sweet (front tip) • Sour (sides) • Umami (taste enhancers such as MSG that are savory)

10. Tips for evaluating smell • Take several small “bunny sniffs” • Block nose & briefly chew food then release nose & breathe in deeply • Breathe fresh air between to avoid fatigue

11. Factors affecting taste sensitivity • Time • Concentration • Temperature • Taste interactions • Taste fatigue • Age (?)

12. Experiment on your tongue • Let’s taste test! Materials Needed: cotton swabs water small cups or glasses unsweetened baking cocoa lemon juice salt honey pens and paper for charting

13. Instructions for Tongue Mapping • Ask a friend to help. One of you will be the taster and the other will be the tester. When the first person is done tasting, you can switch so both of you will get a chance to taste. • Put a little bit of each substance in a cup. Mix the non-liquids with some water so that all the substances have about the same consistency. • Draw a chart for recording your results. Along the left side of the paper write each of the foods you will test in a separate row. Use unsweetened baking cocoa and water to test bitter, lemon juice to test sour, honey to test sweet, and saltwater to test salty. Across the top draw three columns for each taster. Label each with the taster's name and "front," "back," and "side." • Make some predictions. Do you think different places on your tongue will taste different flavors more intensely? Where on your tongue do you think each flavor will taste strongest? Will some flavors be easier or harder to taste than others? • Have the tester dip a cotton swab into one of the liquids and dab it either on the front, back or side of the taster's tongue. • The taster tastes the liquid, then takes a sip of water. This helps clear your tongue of the taste so it doesn't interfere with the next part of the experiment. • The tester then dips a new cotton swab in the same liquid and dabs it on a different part of the taster's tongue. The taster tastes the liquid again and sips some water. Now, try it again on the third part of the taster's tongue. • Once all the parts of the tongue have tasted the liquid, the taster says which part of his tongue tasted the liquid the strongest. The tester records the taster's answer on the chart. • Follow the same process for each of the different liquids. Then switch who tastes and who tests and do the whole taste test again with the new taster. • When all tasters have finished testing, talk about your results. Were your predictions correct? Did some of your results surprise you? Did both tasters taste the same things on the same parts of your tongues?