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Question 1

Sensory evaluation

Answer 1

Analysis of the taste, smell, sound, feel and appearance of food

Question 2

Characteristics that influence like or dislike of food

Answer 2

Physical (body chemistry, number of taste buds, age, gender)
Psychological (taste bias is like or dislike linked to past experience, label terms, advertising, peers)
Cultural (beliefs and behaviors)
Environmental (availability, economical)

Question 3

Sensory characteristics of food

Answer 3

Appearance (colorimeter measures color in foods in terms of hue, value, chroma)
Flavor (KEY, taste by taste buds, foods like lemon tea sourballs = astringency. Temperature can affect flavor. Aroma is odor and part of flavor), volatiles in contact with olfactory bulb
Texture (chewiness =elastic resistance, graininess= chia seeds, brittleness=fragility, firmness=carrots, consistency=puree compared to)

Question 4

Test panels

Answer 4

Taste test panel evaluates food flavor, texture, appearance and aroma by TRAINED panelists that discern subtle differences when developing new products.
Consumer test panel determine products the average consumer will prefer. UNTRAINED panelists.

Question 5

Control of influencing factors

Answer 5

Peer influence so panelists must be in different booths
Environmental factors so booths completely isolated, warm water between samples, samples at same temperature
Psychological biases so 3-digit codes to prevent biases from 1,2,3 or ABC coding. Only 4-5 samples at a time.

Question 6

Evaluating form has to be

Answer 6

Numerical scoring to rank items
Verbal label to describe
Universal simples images to convey a person

Question 7

Food chemistry

Answer 7

Branch of food science that deals with chemical composition of foods, physicochemical properties of food components, physicochemical changes that occur in food during handling, processing, storage and chemical basis of functional properties of food ingredients.
Chemical comp: molecules in the food
Physicochemical properties: molecular structure, physical properties (mp,bp, solubility), interactions with other components in food
Chemical changes during handling, processing, storage: same as above but with handling,processing,etc

Question 8

pH, food preservation, baking, eggs

Answer 8

Botulism: > 4,6
Yeasts: 4<7
Molds: 2<8,5
Acids (from lemon, cream of tartar) develop white color
Basic (chocolate cakes) have a darker color
Eggs become more basic in storage as CO2 escapes through egg shell
Mousse, soufflés and meringues need fresh eggs because their thicker egg whites trap more air

Question 9

Functional property and functional food

Answer 9

Contributions that individual ingredients make to characteristics of food: structure, texture, appearance, shelf life.
Functional property, functional role or functionality can be used interchangeably but not functional group!! (atom groups)
Functional food: any food or food ingredient that may provide a health benefit beyond the nutritional value of the nutrients it contains or a food that has an ingredients added to give physiological benefit not nutritionally related
ex: probiotic yogurt, cereal with added fiber, eggs with omega3, orange juice with added calcium, but vitC orange is not considered

Question 10

Nutraceuticals

Answer 10

Any naturally derived bioactive compounds that are found in foods, dietary supplements or herbal products and have health-promoting, disease-preventing, or medicinal properties. Dietary supplements are sold as capsules, tablets and functional foods are sold as beverages/foods.

Question 11

Minor chemical constituents

Answer 11

Minerals, vitamins, acids, pigments, flavors, additives. Nutritional, aesthetic/functional are way bigger than their minor contribution to chemical composition.

Question 12

Intro to carbohydrates

Answer 12

Contain multiple hydroxyl groups H-C-OH that participate in Hbonds (intra and inter molecular)
Sugars = monosaccharides and disaccharides
Oligosaccharides (3-10)
Polysaccharides (>10) like starches (hemi)celluloses pectins gums

Question 13

Intro to proteins

Answer 13

Polymers of amino acids linked by peptide bonds (from dehydration)

Question 14

Intro to lipids

Answer 14

Fats/oils, waxes, cholesterol, sterols, vitamins
Majorly composed of triglycerides (glycerol with FA)
Products of esterification: carboxylic acid + alcohol = ester + eau

Question 15

Carbohydrates (Structure)

Answer 15

Crystalline state = cyclic structure
When dissolved in water, cyclic structure is in equilibrium with open chain form, which is the highly active ones. In open-chain form (1%), one of the hydroxyl group becomes a carbonyl (C=O) (aldehyde or ketone). Glycosidic bond by removal of water molecule to create a disaccharide

Question 16

Oligosaccharides

Answer 16

Oligosaccharides are foods for intestinal microflora because we cannot digest them. They produce some organic acids and gas. Organic acids are the only source of calories from FOS or GOS. Can be used as low-calorie sweetening agent

Question 17

Pre/probiotics

Answer 17

Prebiotics: substances (like FOS, GOS) that favor growth of commensal bacteria
Probiotics: Commensal bacteria that we ingest

Question 18

Polysaccharides

Answer 18

Starch is the most common. Found as water-insoluble granules in the endosperm (2umrice to 100um potato). Made of glucose. Unbranched= amylose, a-d-glucose units (250-300). Branched = amylopectin, branched after 15-25, 1000units.

Question 19

Properties of starch

Answer 19

Starch is insoluble because of Hbonds between starch molecules. When heated, the starch Hbond network is disrupted because of high energy -> molecules get further and water can get in. Beyond the gelatinization T, starch molecules can be leached in the water and if continues, it causes rupture and low viscosity. If done right, formation of a gel. After cooking, starch molecules reform Hbonds and becomes firmer. After a certain time, continuous Hbond reformation forces water out of the gel to create syneresis

Question 20

Differences in starch sources

Answer 20

Size of starch granules
Amylose/amylopectin ratio
Average length of amylose and amylopectin chains
Affects gelatinization behavior and tendency for retrogradation because of effects on hydrogen bonding

Question 21

Chemical modifications of starch lead to

Answer 21

Pregelatinized starch, hydrolyzed starch, cross-linked starch, derivatized starch can be obtained.Thickening and gelling agents as well.

Question 22

What is high-fructose corn syrup?

Answer 22

HFCS 55 is sweeter than HFCS 35 because there is 55% of the glucose that has become fructose which is sweeter than glucose.

Question 23

Cellulose

Answer 23

Structural plant starch that is not digestible by humans because of the b-glycosidic bonds. Therefore, can be used for providing components in food without adding calories to products.

Question 24

What is MCC (microcrystalline cellulose)?

Answer 24

Food additive produced by partial depolymerization of cellulose. Anti-caking agent in cheese, stabilizes foams and emulsions. Reduces fats and oils in low fat hot dogs.Forms gel to improve adhesion of sauces. Tabletting agent.

Question 25

What is CMC (carboxymethylcellulose)?

Answer 25

Chemically modified cellulose by replacing CH2OH groups by CH2COOH groups to increase solubility in water. Used to increase viscosity, forms weak gels, ice cream to retard ice crystals formation.

Question 26

Other polysaccharides

Answer 26

Polymers of sugars others than glucose.
Vegetable gum are derived from trees. Act as stabilizers, gelling agents or thickeners.
Guar gum, arabic gum, karaya gum, tragacanth gum
Pectins found in plant cells and made of sugar acids, substitutes gelatine in any vegan products.

Question 27

Properties of carbohydrates in food industry

Answer 27

Sweetening: aspartame(artificial), fructose, xylitol sucrose, glucose, lactose. Inverted sugar from sucrose to glucose and fructose by hydrolysis (invertase enzyme) to avoid instability of glycosidic bond
Fermentable: conversion of sugars to alcohol and CO2/organic acids by microorganisms and these conditions inhibit growth of other microorganisms.
Flavor and color (Maillard and caramelization): reaction between open-chain of sugars and amine group of amino acids and proteins (volatile compounds are formed). Cara: heating concentrated sugar solution to break down sugar molecules and polymerize them.
Mouthfeel (viscosity): high sugar concentration (honey, syrup) = high viscosity. Diet soft drinks are sweetened with artificial so not same texture. Sugar alcohol may be added.
Preservatives: draw water away from bacteria, maintain moistures in cakes (invert sugar is best in cakes)
Tenderizers: More sugar = more tender. Sugar interferes with flour ability to form elastic texture.