Sensory evalutation Flashcards
def sensory evaluation + 4 influences on food likes and dislikes
SENSORY EVALUATION: analysis of the taste, smell, sound, feel and apperance of food
1. PHYSICAL: body chemistry, age, gender, number of taste buds affect the abiliy to detect flavors 2. PSYCHOLOGICAL: - TASTE BIAS: it is a like or dislike that is linked to past positive or negative experiences - Label terms, brand names, advertising, peers, and setting also cause taste bias 3. CULTURAL: beliefs and behaviours strongly influence exposures to food and resulting food preferences 4. ENVIRONMENTAL: - People are more likely to eat what is available and economical - Immediate surrundings affect food preferences
4 sensory characteristics of food product
- APPEARANCE (shape, size, color..)
- Colorimeter= device that measures the color of foods in terms of hue, value and chroma
- Colored lights may be used in a sensory evaluation to prevel color from influencing taste panel
- FLAVOR: combine of taste + aroma
- Taste throught the taste buds
- 5 basics tastes: bitter, satly, sour, savory, sweet
- Aroma= odor of food
- ASTRINGENCY= foods like tea,lemons,sourballs
- Temperature can affect - ODOR:
- Result from volatile particles coming in contact with the olfactory bulb
- The brain links various nerve stimulations with specific foods and experiences - TEXTURE
5 types of texture
- CHEWINESS: the ability to slide without breaking
- GRAININESS: size of the particles
- BRITTLENESS: how easily a food breaks apart
- FIRMNESS: foods resistance to pressure
- CONSISTENCY: the thinness or thickness
taste test panels
- Taste test panel: evaluates food flavor, texture, appeaarance + aroma
- Trained panelists discern subtle sensory differences, as when developing new products
- CONSUMER TEST PANELS: help determine products the average consumer will prefer
- These untrained panelists represent the buying public by:
1. Comparing a new product to one on the market
2. Evaluating new types of products
psychological biases
- Scientists identify samples with 3-digit codes to prevent a bias for the lowest numer (1) and the letter thats starts (A)
- Tasters can judge 4-5 samples at one time
evaluation form taste panel
- Participants fill out an evaluation form that may be a:
- Numerical scoring system form that allows the ranking oof the food items
- Verbal labels form that describes various attributes of each food item
- Universal form that uses simple images to convey how a person feels about the food
definition food chemistry
Food chemistry: the branch of food science that deals with the CHEMICAL COMPOSITION OF FOODS, the PHYSICOCHEMICAL (physical and chemical) PROPERTIES OF FOOD COMPONENTS, the processing, the storage, and the chemical basis of FUNCTIONAL PROPERTIES of food ingredients
basic of food chemistry
CHEMICAL COMPOSITION OF A FOOD: what molecules is the food made of?
PHYSIOCOCHEMICAL PROPERTIES OF THE FOOD COMPONENTS: what is their molecular structure? What are their physical properties (melting point, solubility..)? How do they interact with other components present in the food or in the atmosphere (O2, H2O)?
CHEMICAL CHANGES DURING HANDLING, PROCESSING, AND STORAGE: changes in molecular structure, chemical decomposition, chemical reactions with other components in the food or in the atmosphere…
pH
- Knowing th pH environment in which bacteria grow is crucial to preserving food and keeping it safe
- BOTULISM: is caused by a toxin that affects low-acids foods with a pH above 4.6
- YEASTS grow in a pH range from 4 to 7
- MOLDS grow in pH range from 2 to 8.5
pH and baking + eggs
The pH changes in batters and doughs affects color and texture of baked products:
1. ACID (ex;lemon juice or cream of tartar) are added to angel food cake to develop THE WHITE COLOR 2. Chocolate cakes have a DEEPER, DARKER COLOR and smoother flavor if the batter is more BASIC - Eggs become more basic in storage as CO2 escapes trhough the egg shell Ex: mousse, soufflés and meringues need fresh eggs because their thicker egg whites trap more air
definition functional foods + examples
- Any foof or food ingredient that may provide a health benefit beyong the nutritional value of the nutrients it contains
Or- An ordinary food that has components or ingredients added to give it a specific medical or PHYSIOLOGICAL benefit, other than a purely nutritional effect
Ex: probiotic yogurt, cereals with added soluble fiber, eggs enriched with omega 3 FA
** VIT C content of an orange does not make it a functional food!!
Orange juice is fortified with calicum would be classified as one
nutraceuticals
Any naturally derived BIOACTIVE COMPUNDS that are found in foods, dietary supplements, or herbal products and have health-promoting, disease preventing, or medicinal properties
dietary supplements vs functional food
Dietary supplements are typicall sold in capsules, tablets or other pharmaceutical-type formats while functional foods are sold as foods/beverages
minor vs major
MINOR:
- Vitamins - Minerals - Acids (organic/inorganic) - Pigments/colors - Flavors - Additives * * these minor constituents exert significant NUTRITIONAL, AESTHETIC AND OR FUNCTIONAL ROLES well beyond their relatively minor contribution to the overall chemical composition of a food product
MAJOR:
- Carbohydrates - Lipids (fat/oils) - Proteins - Water * * except for water, there are all large and complex classes of biomolecules
carbohydrates
- Carbohydrates have the molecular formula : CmH2nOn = Cm(H2O)n ** not represent the molecular structure
- This molecular formula gave rise to the name carbohydrate (hydrates of carbon)
- Structurally, they contain multiple hyrdoxyl groups H-C-OH which participates in hydrogen bonding including with water
