SUBJECTS
|
BROWSE
|
CAREER CENTER
|
POPULAR
|
JOIN
|
LOGIN
Business Skills
|
Soft Skills
|
Basic Literacy
|
Certifications
About
|
Help
|
Privacy
|
Terms
|
Email
Search
Test your basic knowledge |
Food Chemistry
Start Test
Study First
Subjects
:
engineering
,
chemistry
Instructions:
Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can
study here
.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.
This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.
1. What is the name of the structural carbohydrate found in lobsters crab - shellfish - and insects?
Chitin
Primary butyric acid also caproic acid.
A concentrate of microfibrillar proteins of fish muscle.
Sucrose
2. What are the three stages of oxidative rancidity?
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Pectin methyl esterase or galacturonase
Initiation - Propagation - and Termination
3. What two types of compounds are joined with an ester bond to make a wax?
Speed of Light
Fatty Acid and Alcohol
An enzyme that converts hydrogen peroxide to water plus oxygen.
It explodes
4. What is Carboxy-methyl cellulose often used for?
Onions ( or leeks)
45% - 52% - 90%
Four
Thickener in foods
5. At low water activity What is the main deteriorative concern?
1 - 3 - 7-trimethylxanthine
Oil in Water
Lipid oxidation
Lipase
6. Name three effects of protein denaturation.
Covalent (strongest) and Hydrophobic (Weakest)
Orange Juice
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
14
7. What happens to chlorophyll on heating?
Thermus Aqauticus
Speed of Light
Pectin methylesterase & polygalacturonase
Pheophytin forms
8. Name 3 chemical agents capable of denaturing proteins.
Bright green
Emulsification
Whole Milk
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
9. What metabolic disorder prevents conversion of phenulalanine to tyrosine by normal metabolic pathways?
Sweet - Salty - Sour - and Bitter
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Phenylketonuria
Olive Green
10. Name a naturally occurring protein sweetener.
Sodium chloride reduces foam stability and sucrose improves foam stability.
Thamautin
Cis
Monosodium Glutamate
11. What are the fructose contents in commercial HFCS products.
Racemic Mixture
Yes
45% - 52% - 90%
Sodium bicarbonate generates CO2
12. What is the geometric configuration of double bonds in most natural fatty acids?
HLB (hydrophilic-lipophilic balance); a low value (3-6) promotes water in oil emulsions and a high value (8-18) promotes oil in water emulsions.
D: None of the above
Cis
Initiation - Propagation - and Termination
13. If oxygen attacks an unsaturated fatty acids at the double bond What is the resultant product?
D: None of the above
Two aldehydes
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Monosodium Glutamate
14. In the enzyme Taq Polymerase What does Taq stand for?
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Fructose
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Thermus Aqauticus
15. What are colloids that are stabilized by a layer of solvation called?
Orange Juice
Blue pigment in flowers
Emulsoids
Acetoin
16. Which two amino acids is the aspartame derived from?
Phenophylin
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Aspartic Acid and Phenylalanine
Acetoin
17. At low water activity What is the main deteriorative concern?
D: None of the above
Lipid oxidation
1 - 3 - 7-trimethylxanthine
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
18. What does the saponification value measure and how is it measured?
Covalent (strongest) and Hydrophobic (Weakest)
Acetoin
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Pectins
19. What would be a safe processing time for heat processing green beans in a boiling water bath? A. 30 minutes B. 300 minutes C. Depends on the size of the food container D. None of the above
pH 3-5
D: None of the above
Blue pigment in flowers
Ascorbic Acid and Citric Acid
20. How does ERH relate to water activity?
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
.05
ERH=100 x Aw
21. What toxic pigment is found in cottonseed endosperm?
Gossypol (it is removed during the oil refining process)
Browning of freshly cut surfaces of fruits and vegetables.
They act as catalysts - speeding the polymerization of acrylamide.
Orange Juice
22. What does MSG stand for?
pH 3-5
HPLC has higher pressure than FPLC
Lipase
Monosodium Glutamate
23. Which of these foods is not appropriate to this list? A) Salami B) Yogurt C) Orange Juice D) Beer
Orange Juice
Acsulfame-K - Saccharin - Cyclamate - Aspartame
pH below positive charge; pH at no charge; pH above negative charge
Fatty Acid and Alcohol
24. Name 4 advantages of using enzymes in food processing.
They act as catalysts - speeding the polymerization of acrylamide.
HPLC has higher pressure than FPLC
They are natural - nontoxic substances - generally catalyze without unwanted side-effects - active under very mild conditions of temperature and pH - active at low concentrations - rate of reaction can be controlled - can be inactivated after reactio
Fatty Acid (Ester linked) to Fatty Alcohol
25. Name the three positively charged amino acids.
Carrageenan
Lysine - Arginine - and Histidine
Four
Pheophytin forms
26. What enzyme causes hyrolytic rancidity in milk?
.05
Lipase
Chitin
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
27. Which of these foods is not appropriate to this list? A) Salami B) Yogurt C) Orange Juice D) Beer
Emulsoids
Nucleation or crystal formation and crystal growth.
Orange Juice
Capsaicin
28. What are the limiting amino acids in corn - potato - and green peas?
Sodium chloride reduces foam stability and sucrose improves foam stability.
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
14
Four
29. A chlorophyll molecule reacting with magnesium exhibits what shade of green?
Bright green
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Troponins and Tropomyosin
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
30. What is the chemical nature of anthocyanins?
Water
Glycosides of anthocyanidins
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
V=IR and P=VI or I x I x are
31. What is the name given to a mixture of equal parts of Darel Lisomers?
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Lysine - Arginine - and Histidine
Racemic Mixture
32. Which of the following examples of browning is enzymatic in nature? 1. Browning of sugars as a result of heating 2. Browning of freshly cut surfaces of fruits and vegetables 3. Browning of bread during toasting 4. Browning of potato chips
Prolamines
Fat Oxidation
Browning of freshly cut surfaces of fruits and vegetables.
Pheophytia does not have magnesium in porphyrin ring.
33. What is the movement of molecules through a semi permeable membrane from a region of low to high solute concentration called?
Tryptophan
Osmosis
The speed of a molecule is proportional to the surrounding voltage gradient.
Covalent (strongest) and Hydrophobic (Weakest)
34. What is the name of the degradation compound of chlorophyll?
Pectin Esterase - Polygalacturonase - Pectin Layase
Water
Phenophylin
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
35. What charge will a protein have when the pH of its solution is below at - and above its pKa?
Pectin Esterase
Anthocyanins
pH below positive charge; pH at no charge; pH above negative charge
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
36. If you take 20 ml of .1 M NaOH to titrate 40 mL of an HCL solution to the penolphthalein end point What is the molarity of the HCL solution?
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
.05 M HCL
DNA transferred by cell to cell contact (bacterial sex).
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
37. What are proteins which are soluble in 50-80% ethanol known as?
Ammonia - Water - Carbon Dioxide
A concentrate of microfibrillar proteins of fish muscle.
Thickener in foods
Prolamines
38. What does HLB stand for and What does a high and low HLB value indicate?
Polyphenol Oxidase
HPLC has higher pressure than FPLC
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
HLB (hydrophilic-lipophilic balance); a low value (3-6) promotes water in oil emulsions and a high value (8-18) promotes oil in water emulsions.
39. Name the two components that comprise the relaxing factor in muscle fibers.
Gliadins and Glutenins
Egg white proteins - the globin part of hemoglobin - bovine serum albumin - gelatin - whey proteins - casein micelles - B-casein - wheat proteins - soy proteins - and some protein hydrolyzates.
Troponins and Tropomyosin
Erythorbic Acid
40. What chemical compound is responsible for the 'hot' principle of jalepeno peppers?
Prolamines
Pectin Esterase - Polygalacturonase - Pectin Layase
Emulsification
Capsaicin
41. What metabolic end product does the Voges-Proskauer test detect?
Phenylketonuria
Polyphenols
Acetoin
Phenophylin
42. What degradative enzyme causes browning in apples - pears - bananas - and peaches?
Polyphenoloxidase
Sodium chloride reduces foam stability and sucrose improves foam stability.
Pectin methyl esterase or galacturonase
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
43. What is the major color compound in tomatoes?
Fatty Acid and Alcohol
Lycopenes
Pectin Esterase - Polygalacturonase - Pectin Layase
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
44. Food additive that could be used to prevent cocoa particles from settling in chocolate milk
Fructose
Pectin methylesterase & polygalacturonase
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Carrageenan
45. What pigment was first designated as anthocyanins?
Bright green
Capsaicin
Blue pigment in flowers
Aspartic Acid and Phenylalanine
46. What is the common name for 9 12 - cis-cis-octa dienoic acid?
Parabens
Phenophylin
Linoleic Acid
Orange Juice
47. What are the three stages of oxidative rancidity?
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Degradation of protein and production of acid from sugar at the same time.
Carrageenan
Initiation - Propagation - and Termination
48. Name three non-nutritive sweeteners approved for use in USA?
Pectin methyl esterase or galacturonase
Initiation - Propagation - Termination
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Acsulfame-K - Saccharin - Cyclamate - Aspartame
49. Name two enzymes that are involved in softening fruits.
Pectin Esterase - Polygalacturonase - Pectin Layase
DNA transferred by cell to cell contact (bacterial sex).
Ascorbic Acid and Citric Acid
Monosodium Glutamate
50. Name two enzymes that are involved in softening fruits.
Pectin Esterase - Polygalacturonase - Pectin Layase
Bright green
Plasmids
Initiation - Propagation - Termination