Test your basic knowledge |

Food 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 fundamental driving of electrophoresis?
pH below positive charge; pH at no charge; pH above negative charge
The speed of a molecule is proportional to the surrounding voltage gradient.
Prolamines
Ascorbic Acid and Citric Acid

2. A chlorophyll molecule reacting with magnesium exhibits what shade of green?
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
RNA transcribed to DNA
Initiation - Propagation - Termination
Bright green

3. What does HLB stand for and What does a high and low HLB value indicate?
D: None of the above
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.
Phenylketonuria
Initiation - Propagation - and Termination

4. How do sodium chloride and sucrose affect foam stability?
Pheophytia does not have magnesium in porphyrin ring.
Sodium chloride reduces foam stability and sucrose improves foam stability.
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Chlocophyllide does not have a phytoltail

5. How can a molecular weight of protein - DNA - and RNA be determined?
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
The speed of a molecule is proportional to the surrounding voltage gradient.

6. Which of these foods is not appropriate to this list? A) Salami B) Yogurt C) Orange Juice D) Beer
Thermus Aqauticus
Orange Juice
Bitter
Polyphenol Oxidase

7. What does the acronym NPN stand for?
Whole Milk
Non-protein nitrogen
Thamautin
Yes

8. What enzyme causes hyrolytic rancidity in milk?
A concentrate of microfibrillar proteins of fish muscle.
Lipase
Pheophytin forms
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents

9. What kinds of food emulsions are? (1) Butter (2) Mayonnaise(3) Milk
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Primary-amino acid sequence. Secondary-alpha-helix - beta sheet. Tertiary-one complete protein chain with cross bonds linking it together. Quaternary-four separate protein chains assembled as one.
V=IR and P=VI or I x I x are
Butter= water in oil Mayonnaise= oil in water Milk= oil in water

10. 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
D: None of the above
Daminozide
Lysine - Arginine - and Histidine
Sucrose

11. Is a disaccharide
Thickener in foods
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Sucrose
Lamellar; Hexagonal I - II; Cubic

12. How does HPLC differ from FPLC?
Thermus Aqauticus
HPLC has higher pressure than FPLC
Yellow
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.

13. 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
Negative log of the hydrogen concentration (mol/l).
Browning of freshly cut surfaces of fruits and vegetables.
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
.05 M HCL

14. Name three compounds capable of poisoning the catalyst during commercial hydrogenation.
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Phenophylin
Phenylketonuria

15. Food additive that could be used to prevent cocoa particles from settling in chocolate milk
Nucleation or crystal formation and crystal growth.
Parabens
Carrageenan
Fatty Acid and Alcohol

16. Which two amino acids is the aspartame derived from?
Lycopenes
Yes
Aspartic Acid and Phenylalanine
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.

17. Name a naturally occurring protein sweetener.
Thamautin
Yellow
An enzyme that converts hydrogen peroxide to water plus oxygen.
Chlocophyllide does not have a phytoltail

18. What does the iodine value measure and how is it measured?
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
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.

19. What toxic pigment is found in cottonseed endosperm?
Gossypol (it is removed during the oil refining process)
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Sweet - Salty - Sour - and Bitter
Ascorbic Acid and Citric Acid

20. What degradative enzyme causes browning in apples - pears - bananas - and peaches?
Gossypol (it is removed during the oil refining process)
Polyphenoloxidase
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Chitin

21. What is the protein efficiency ratio (PER) of casein?
2.5
Water
Primary butyric acid also caproic acid.
Orange Juice

22. What are soluble polymers of anhydro-galacturonic acid and its esters called?
Fructose
Two aldehydes
The speed of a molecule is proportional to the surrounding voltage gradient.
Pectins

23. What is surimi?
Glycosides of anthocyanidins
A concentrate of microfibrillar proteins of fish muscle.
RNA transcribed to DNA
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.

24. What is the structural difference between chlorophyll and pheophytia?
Sucrose
Negative log of the hydrogen concentration (mol/l).
Pheophytia does not have magnesium in porphyrin ring.
Pectin Esterase - Polygalacturonase - Pectin Layase

25. What does Reichert-Meissert Number measure?
Bright green
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Monosodium Glutamate
Primary butyric acid also caproic acid.

26. Name 4 advantages of using enzymes in food processing.
HPLC has higher pressure than FPLC
Racemic Mixture
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
Lycopenes

27. What is the chemical nomenclature for caffeine?
Non-protein nitrogen
1 - 3 - 7-trimethylxanthine
Covalent (strongest) and Hydrophobic (Weakest)
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.

28. What is the fundamental driving of electrophoresis?
The speed of a molecule is proportional to the surrounding voltage gradient.
Arachidonic Acid
Speed of Light
Fructose

29. Name three factors useful in controlling enzyme activity.
Sweet - Salty - Sour - and Bitter
Lycopenes
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Fat Oxidation

30. 20 grams of amylose is added to 80 grams of water in a bearker; the boiling point is measured with an ordinary mercury-in-glass thermometer. What is the observed boiling point of the material in the beaker?
Lipase
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
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.
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants

31. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
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
Olive Green
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Anthocyanins

32. 20 grams of amylose is added to 80 grams of water in a bearker; the boiling point is measured with an ordinary mercury-in-glass thermometer. What is the observed boiling point of the material in the beaker?
Acsulfame-K - Saccharin - Cyclamate - Aspartame
14
Prolamines
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)

33. Which amino acid has the greatest molecular weight: tryptophan or tyrosine?
Primary-amino acid sequence. Secondary-alpha-helix - beta sheet. Tertiary-one complete protein chain with cross bonds linking it together. Quaternary-four separate protein chains assembled as one.
Tryptophan
Primary butyric acid also caproic acid.
Polyphenoloxidase

34. Alar is the trade name for what chemical compound?
Thamautin
Daminozide
Pectin methylesterase & polygalacturonase
Lycopenes

35. Name the two components that comprise the relaxing factor in muscle fibers.
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Acetoin
Troponins and Tropomyosin
Pectins

36. Name 2 heat stable enzymes in food that are important to the quality of aseptic products.
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
2.5
Lamellar; Hexagonal I - II; Cubic
Sodium bicarbonate generates CO2

37. When heated ammonium bicarbonate decomposes to form what end products?
Fat Oxidation
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Thamautin
Ammonia - Water - Carbon Dioxide

38. What compounds oxidize to form brown color in fruits and vegetables?
Initiation - Propagation - Termination
Polyphenol Oxidase
Anthocyanins
Polyphenols

39. Name a commonly used household chemical leavening agent and the gas it generates.
Emulsification
Polyphenols
Sodium bicarbonate generates CO2
No

40. What is the main class of color compounds found in raspberries?
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Anthocyanins
Two aldehydes
Lysine - Arginine - and Histidine

41. Name two reasons why fats are hydrogenated.
Sweet - Salty - Sour - and Bitter
An enzyme that converts hydrogen peroxide to water plus oxygen.
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.

42. What is the enzyme responsible for browning in apples and lettuce?
.05
Polyphenol Oxidase
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Arachidonic Acid

43. What are the three main steps in the autooxidation of lipids?
Plasmids
Initiation - Propagation - Termination
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Thamautin

44. What is the name of the degradation compound of chlorophyll?
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Phenophylin
Olive Green
Emulsoids

45. 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
Glycosides of anthocyanidins
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Blue pigment in flowers
Browning of freshly cut surfaces of fruits and vegetables.

46. Match the number of carbon atoms with the common name of these saturated fatty acids. Carbon #: 4:0 10:0 - 12:0 -14:0 - 16:0 - 18:0Common Name: Myristic - Butyric - Capric - Lauric - Stearic - Palmitic
Gossypol (it is removed during the oil refining process)
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Four
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)

47. Name 3 factors influencing the consistency of commercial fats.
ERH=100 x Aw
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
An enzyme that converts hydrogen peroxide to water plus oxygen.
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.

48. Name two non-enzymatic browning reactions.
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Covalent (strongest) and Hydrophobic (Weakest)
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Carmelization and Maillard

49. What is Ohm's Law and What is Power Equation?
45% - 52% - 90%
Fructose
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.
V=IR and P=VI or I x I x are

50. If the absorption of a sample is being determined spectrophotometrically at 420 nm what color is the sample?
Yellow
Fatty Acid and Alcohol
Anthocyanins
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.