Chapter 1: Basic Foods Flashcards
Measurement of physical and chemical properties of food using equipment or mechanical devices
Objective evaluation
Measurement of the characteristics of food as perceived by the senses (sight, smell, taste, touch, and hearing)
Subjective evaluation
Designed to determine whether detectable differences exist between products
Difference test
To determine acceptability and to define the direction in which the project should move
Single sample
Test difference
Test of 2 samples presented to identify the sample with the greater amount of the characteristics being measured
2 different products 2 sample test
Paired comparison
Two samples are provided, and panelists are asked to identify which sample is higher in a particular attribute
Paired comparison
You present three samples to panelists: two are the same, and one is different. The task is to identify the odd one out.
Triangle test
3 samples are presented simultaneously with 2 samples alike, can either be the control or the variable
Judge must identify the ODD sample
Triangle test
a test of difference
3 samples: 1 variable, 2 controls
Duo-trio test
You provide a reference sample followed by two test samples: one matches the reference, and the other differs. Panelists must determine which test sample matches the reference.
Duo-trio test
Judges are asked to rate the quality of the food
Scoring test
Use of descriptive words to characterize food samples
Judges are asked to describe the products (dull green, bright green, green)
Descriptive test
Used when several samples need to be evaluated for a single characteristic
Rank order/ranking test
Employs a pleasure scale or degree of liking or preference
Hedonic scale may be 5, 6, 9 steps - end of the scales being the extremes of preference or non-preference
Hedonic method
Designed to provide information on selected characteristics and to indicate preference or acceptability of the product
Preference/acceptability test
Physical and environment requirements: Temperature and relative humidity
Temp: 25C
Humidity: 40%
Selected from panel who is available at test site and are willing to participate
200 or more
Consumer panel
Expert tester (1-2 members); laboratory panel (9-12 members)
Trained panel
Untrained on product evaluation to be undertaken
50 members
Naive panel
Cassava, sweet potato, white potato, gabi, ubi, taro
Roots and tubers
Garlic, onion, shallot
Bulbs
Beans, monggo, patani
Seeds
Broccoli, kinchay, labong
Stems and shoots
pechay, spinach, kangkong, lettuce, malunggay, cabbage
Leaves
Cauliflower, kalabasa, broccoli
Flowers
Kalabasa, tomato, kalamansi, patola, cucumber, chayote, eggplant
Fruits
Seeds, roots, and tubers
Carbohydrate-rich
legumes or pulses
Protein-rich
nuts, olives, and avocados
Fat-rich
mushrooms, tomatoes, radish, green leafy vegetables
High moisture content
Green leafy vegetables and yellow fruits are rich in?
Vitamin A
Yellow fruits are rich in?
Vitamin C
pulses and legumes are rich in?
Vitamin B-complex
thin-walled, made-up of cellulose; intercellular spaces are common, resulting in the release of air during cooking of fruits and vegetables
Parenchyma
As the fruit ripens, softening of the tissues occur due to the conversion of?
Protopectin to pectin
long tubes that carry water, salts, and nutrients throughout the plants called xylem and phloem
Contains cellulose and lignins
Do not change during cooking, resulting in stringiness and toughness
Conducting
made up of cellulose that thickens when the plant matures
Supporting
specialized parenchyma cells that secrete cutin and suberin, resulting in thick corky cells
Protective cells
cellulose, hemicellulose, and lignin
Excreted undigested, provides bulk but not energy
Insoluble fibers
gums and pectic substances
significant in fruit cookery: pectic substances
Soluble fibers
precursor of pectin, found in immature fruits
Gives hard and crispy texture of immature/unripe fruits
Does not form jelly network w/ sugar
Water-insoluble
Protopectin
water-soluble
can form gels with sugar
important in jelly
pectinic acid or pectin
water-soluble
formed by ripening enzymes in fruit, found in overripe fruits
does not form gels
pectin
best-known flavoring substance in fruits
increases as the fruit ripens
sugar
give the characteristic flavor of fruits and vegetables
esters and aromatic compounds
gives astringent (pakla) quality or puckery favor
tannin
responsible for the characteristic strong flavor and aroma of garlic, onions, and cabbage
intensify during improper cooking; become mild in flavor if cooked or acted upon by enzymes during food prep
volatile sulfur compounds
addition of baking soda forms _____, has bright green color, may be destructive to vitamin B and may be vulnerable to too much softening of the cellulose, results to mushy vegetable
chlorophyllin
pheophytin a: addition of acid turns chlorophyll into what color
greenish gray
pheophytin b: addition of acid turns chlorophyll into what color
olive drab
causes the slightly green appearance of the cooking water
action of enzyme chlorophyllase changes to chlorophyllide, where the phytil tail is removed
colors yellow to orange red
fat-soluble and fairly stable to acid, alkali, metals, and heat, unless excessive
Carotenoids
carotenoid in tomato and watermelon
lycopene
carotenoid in carrots
carotene
carotenoid in corn (2)
cryptoxanthin and xanthin
carotenoid in red peppers (2)
capsanthin and cyrptoxanthin
carotenoid in green peppers (2)
luetin and violaxanthin
carotenoid in pineapple
violaxanthin
water-soluble pigment responsible for red to purple to blue colors
stable in acidic medium and heat
changes of unpalatable blue color in presence of alkali
anthocyanin
changes anthocyanin to colorless
causes browning in foods when oxidized
anthocyanase
