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. Name two enzymes that are involved in softening fruits.
Lamellar; Hexagonal I - II; Cubic
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.
14
Pectin Esterase - Polygalacturonase - Pectin Layase

2. What are soluble polymers of anhydro-galacturonic acid and its esters called?
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Pectins
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Four

3. What pigment was first designated as anthocyanins?
Glycosides of anthocyanidins
Blue pigment in flowers
The speed of a molecule is proportional to the surrounding voltage gradient.
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

4. What effect would the addition of sodium bicarbonate have to chocolate?
Two aldehydes
Carmelization and Maillard
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
pH 3-5

5. What is the movement of molecules through a semi permeable membrane from a region of low to high solute concentration called?
Osmosis
Troponins and Tropomyosin
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Pectin methyl esterase or galacturonase

6. What is Ohm's Law and What is Power Equation?
Polyphenol Oxidase
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
V=IR and P=VI or I x I x are
NaCl (it dissociated to a 2M solution)

7. Which amino acid has the greatest molecular weight: tryptophan or tyrosine?
No
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Tryptophan
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls

8. A) Is the major component of most foods.B) Controls shelf-life or storage capabilityC) Regulates chemical and microbiological reactionsD) All of the above
Olive Green
Gossypol (it is removed during the oil refining process)
ERH=100 x Aw
Water

9. How does ERH relate to water activity?
ERH=100 x Aw
Milk
Carrageenan
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.

10. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
pH 3-5
Bright green
Olive Green
Anomeric

11. What is the winterization process for an oil?
Polyphenol Oxidase
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Initiation - Propagation - Termination
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).

12. Name two main gluten proteins.
Sodium chloride reduces foam stability and sucrose improves foam stability.
Emulsification
Gliadins and Glutenins
An enzyme that converts hydrogen peroxide to water plus oxygen.

13. Name two non-enzymatic browning reactions.
Carmelization and Maillard
DNA transferred by cell to cell contact (bacterial sex).
Pectin methyl esterase or galacturonase
1 - 3 - 7-trimethylxanthine

14. What is the major color compound in tomatoes?
Thamautin
Olive Green
Lycopenes
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.

15. What is a polymorphism?
Oil in Water
Sodium chloride reduces foam stability and sucrose improves foam stability.
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.
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.

16. What is the chemical nature of anthocyanins?
14
Thickener in foods
Glycosides of anthocyanidins
Ascorbic Acid and Citric Acid

17. What is the fundamental driving of electrophoresis?
Polyphenol Oxidase
The speed of a molecule is proportional to the surrounding voltage gradient.
Emulsification
Thickener in foods

18. What is the enzyme responsible for browning in apples and lettuce?
Glycosides of anthocyanidins
Polyphenol Oxidase
Blue pigment in flowers
Pheophytia does not have magnesium in porphyrin ring.

19. What is acid proteolysis?
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.
Pectin Esterase - Polygalacturonase - Pectin Layase
Degradation of protein and production of acid from sugar at the same time.
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.

20. What name is given to the small circular DNA molecules that carry genetic information independently of the main bacterial chromosome?
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Nucleation or crystal formation and crystal growth.
Ascorbic Acid and Citric Acid
Plasmids

21. What is the structural difference between chlorophyll and chlocophyllide?
Orange Juice
Chlocophyllide does not have a phytoltail
Troponins and Tropomyosin
Lipid oxidation

22. What does Acid Degree Value measure and how is it measured?
Phenophylin
Thickener in foods
Pheophytia does not have magnesium in porphyrin ring.
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.

23. What are the fructose contents in commercial HFCS products.
Aspartic Acid and Phenylalanine
45% - 52% - 90%
Non-protein nitrogen
.05

24. What chemical compound is responsible for the 'hot' principle of jalepeno peppers?
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Capsaicin
Four
NaCl (it dissociated to a 2M solution)

25. Name a naturally occurring protein sweetener.
14
Lipase
Thamautin
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

26. Name two main gluten proteins.
Linoleic Acid
Gliadins and Glutenins
Ascorbic Acid and Citric Acid
Osmosis

27. 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
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Tryptophan
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.
Linoleic Acid

28. In what food is butyric acid typically found?
Milk
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Monosodium Glutamate
Carrageenan

29. Name one way foam stability can be assessed.
The degree of liquid drainage or foam collapse (foam reduction) after a given time - the time for total or half-drainage (or half-reduction in volume) - or the time before drainage starts.
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.
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Carrageenan

30. Name the strongest biochemical bond and the weakest biochemical bond.
An enzyme that converts hydrogen peroxide to water plus oxygen.
Onions ( or leeks)
1 - 3 - 7-trimethylxanthine
Covalent (strongest) and Hydrophobic (Weakest)

31. Food additive that could be used to prevent cocoa particles from settling in chocolate milk
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
45% - 52% - 90%
Carrageenan
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.

32. Food additive that could be used to prevent cocoa particles from settling in chocolate milk
.05 M HCL
pH below positive charge; pH at no charge; pH above negative charge
Carrageenan
Speed of Light

33. What does the saponification value measure and how is it measured?
.05
Polyphenol Oxidase
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Sodium chloride reduces foam stability and sucrose improves foam stability.

34. 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.
14
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
Chlocophyllide does not have a phytoltail

35. Name one way foam stability can be assessed.
Lipid oxidation
The degree of liquid drainage or foam collapse (foam reduction) after a given time - the time for total or half-drainage (or half-reduction in volume) - or the time before drainage starts.
Pectin Esterase
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)

36. What does the 'c' stand for in the equation E=mc2?
Lipase
20 carbons and 4 double bonds
Speed of Light
Pectin methyl esterase or galacturonase

37. A) Is the major component of most foods.B) Controls shelf-life or storage capabilityC) Regulates chemical and microbiological reactionsD) All of the above
Initiation - Propagation - Termination
Water
Covalent (strongest) and Hydrophobic (Weakest)
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)

38. What is surimi?
A concentrate of microfibrillar proteins of fish muscle.
Carmelization and Maillard
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Whole Milk

39. Name 4 advantages of using enzymes in food processing.
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
Gossypol (it is removed during the oil refining process)
pH below positive charge; pH at no charge; pH above negative charge

40. What is the name of the degradation compound of chlorophyll?
14
Emulsification
Phenophylin
Fat Oxidation

41. What is the geometric configuration of double bonds in most natural fatty acids?
Chlocophyllide does not have a phytoltail
Cis
Polyphenol Oxidase
Chlocophyllide does not have a phytoltail

42. What compounds oxidize to form brown color in fruits and vegetables?
Cis
Daminozide
Capsaicin
Polyphenols

43. What are two common reducing agents that break disulfide bonds in proteins?
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
20 carbons and 4 double bonds
.05
Fatty Acid (Ester linked) to Fatty Alcohol

44. Name 3 reasons it is advantageous to obtain enzymes from microorganisms.

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183

45. What does HLB stand for and What does a high and low HLB value indicate?
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.
Blue pigment in flowers
Daminozide
Carmelization and Maillard

46. Name two enzymes that are involved in softening fruits.
Pectin Esterase - Polygalacturonase - Pectin Layase
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
The degree of liquid drainage or foam collapse (foam reduction) after a given time - the time for total or half-drainage (or half-reduction in volume) - or the time before drainage starts.
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)

47. 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
Initiation - Propagation - Termination
Browning of freshly cut surfaces of fruits and vegetables.
Polyphenol Oxidase
Linoleic Acid

48. What is acid proteolysis?
Degradation of protein and production of acid from sugar at the same time.
NaCl (it dissociated to a 2M solution)
V=IR and P=VI or I x I x are
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents

49. What are colloids that are stabilized by a layer of solvation called?
Sodium chloride reduces foam stability and sucrose improves foam stability.
2.5
Pheophytia does not have magnesium in porphyrin ring.
Emulsoids

50. What is the protein efficiency ratio (PER) of casein?
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
2.5
Polyphenols
.05