Senses and Freshness: Notes on Food Evaluation

Appearance

• Color: Bright, fresh looking?; Dull and boring?; Does it blend with other foods in the meal?
• Shape: Does it have a shape?; Does it have the shape it should have?; Does the shape add to or take away from the eating experience?
• Appetizing presentation: Is it thrown on a plate or in a bowl?; Is it still in the package when you get ready to eat?; Did anyone take time to decorate or embellish?

Odor

• How does the food smell? You might describe different foods as:
• Smell cues to determine freshness: Smell your meat to check for aroma; if it has an aroma, it may indicate the meat is no longer good or fresh.
• Smell your milk close to or after the “sell by” date to determine if it has a sour smell.
• Odor descriptors (examples):
  • Odorless – No smell at all
  • Pungent – a sharp, strong odor
  • Aromatic – a pleasing smell (e.g., flowers, perfume)
  • Overpowering – the scent dominates the room
  • Earthy – smells like dirt (can be good in some foods like mushrooms)
  • Sweet – a sugary smell
  • Spicy – can cause a tingle or burning sensation from the odor
  • Tart – a sharp, bitter, or sour smell
  • Tangy – a biting, sharp smell
  • Zesty – a fresh, invigorating smell
  • Umami – a meaty or savory smell that deepens flavor perception

Taste

• A small taste can tell you if it is still fresh.
• You might describe different tastes as: cilantro example (taste variation among people).
• Food quality cues:
  • Choose a fruit that is bright in color instead of bruised
  • Meat should be bright red at its freshest; if uncooked and brown, it may be not good
• Taste descriptors:
  • Sweet – a sugary flavor
  • Spicy – can cause a tingle or burning sensation
  • Tart – sharp, bitter, or sour taste
  • Tangy – a biting taste that may cause a tingly feeling
  • Zesty – a fresh or invigorating flavor
  • Umami – a meaty or savory taste that deepens flavor

Texture

• How does the food feel? (mouthfeel) – sometimes called mouthfeel
• Description cues:
  • A squishy fruit or vegetable may indicate overripe produce
  • Hard or crunchy texture may indicate underripe produce
  • Some foods have appealing flavors but disagreeable textures (e.g., coconuts for some people)
• Texture is a key component of sensory experience and can affect overall liking even if taste is favorable

Temperature

• Texture and temperature are both perceived through touch; temperature descriptions include:
  • Creamy – smooth and soft
  • Tender – easy to cut or chew (often used for meat, also pastry)
  • Crispy – light and thin texture (e.g., thin cracker or pizza crust)
  • Chewy – requires more chewing (e.g., dense brownie, caramel)

Safety and Nutrition Implications

• Food temperature can indicate safety; e.g., potato salad with ingredients that must stay refrigerated should not be left out at room temperature for long (tepid temperatures may indicate unsafe conditions).
• Quick safety determinations are important to avoid illness from spoiled foods.
• Nutrient decline after harvest: water-soluble vitamins like ext{Vitamin C} and the ext{B vitamins} decline quickly after harvest; high levels of heat, light, or oxygen contribute to nutrient loss
• Common temperature descriptors for serving or testing:
  • Icy cold
  • Lukewarm
  • Tepid (room temperature)
  • Steaming hot

Your Sensory Preferences

• Consider your eating habits and preferences, which are shaped by:
  • Family traditions
  • Cultural background
  • Financial circumstances
  • Allergies or availability
• Reflect on questions like:
  • Do you like bright yellow bananas or those with freckles?
  • How do you like your steak cooked? Well-done, medium, or rare?
  • Do you eat sushi with raw fish?
  • Do you enjoy coconut pie? Yes or no?
  • Do you prefer hot and spicy or mild salsa?
  • Do you prefer regular Cookies (more crumbs) or soft cookies?
  • Do you prefer sweet or vinegar-based barbecue sauce?
  • Do you crave salty or sweet snacks?
  • Do you like crunchy inclusions in soft foods (e.g., sliced almonds in chicken salad, walnuts in brownies)?

Evaluating Foods Professionally

• Nutritional and sensory professionals use sensory evaluations to measure and assess the qualities of food, including taste, smell, texture, and appearance.
• Some tests are simple (tasting or smelling), while others are very detailed and scientific.
• Purpose of professional evaluation: to maximize product acceptance while keeping production costs down.

Testing Foods

• Sensory evaluation in scientific settings can be very detailed and specific; common methods include:
• Triangle Test:
  • The judge is given 3 samples, two are the same and one is different. Can they identify the odd sample?
  • Example: Participants are given 3 crackers. Two are name-brand, one is generic. Can they tell which is generic?
• Duo-trio Test:
  • Participants are given a reference sample and two other samples, one of which is the same as the reference. Can they tell which is the same?
  • Example: Panelists are given Pepsi in a labeled cup. Then they are supplied with two more unmarked cups, one contains Pepsi and the other contains Coca-Cola. Can they tell which unmarked sample matches the reference sample?
• Texture Profile Analysis:
  • Panelists describe the texture of a food using a word bank of descriptors and may compare two samples (e.g., Cookie A is chewier than Cookie B)
• Time Intensity Analysis:
  • Measures how the intensity of a specific sensory attribute changes over time;
  • Example: This barbecue sauce is tangy, but after 2 minutes it becomes very spicy on the tongue
• Discriminative Tests:
  • Can you tell a difference between two food products? Does one look, taste, or smell better than yesterday’s batch? Does changing the cooking time affect texture?
• Descriptive Analysis:
  • Conducted by trained panelists who use product-specific terms to describe findings
• Hedonic Testing:
  • Focuses on whether the tester likes the food or not; uses a rating scale to describe likes/dislikes, commonly used for consumer taste tests