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Food Chemistry

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Answer 50 questions in 15 minutes.
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Match each statement with the correct term.
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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. How does ERH relate to water activity?
Chlocophyllide does not have a phytoltail
Acetoin
D: None of the above
ERH=100 x Aw

2. Are sorbitol and mannitol sweet?
Chitin
Yes
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
RNA transcribed to DNA

3. What are soluble polymers of anhydro-galacturonic acid and its esters called?
Daminozide
Pectins
20 carbons and 4 double bonds
Microorganisms are very versatile - MO's can be altered by mutations or genetic engineering to produce a greater quantity of enzyme or different enzymes - recovery of enzymes is often easy - readily available - high rate of growth and enzyme producti

4. How can a molecular weight of protein - DNA - and RNA be determined?
Blue pigment in flowers
Negative log of the hydrogen concentration (mol/l).
Pectin methyl esterase or galacturonase
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.

5. Which will be coldest at its freezing point: 1M dispersion of amylose 1M solution of NaCl - distilled water - or 1M solution of sucrose?
Prolamines
NaCl (it dissociated to a 2M solution)
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.
Negative log of the hydrogen concentration (mol/l).

6. Name 3 chemical agents capable of denaturing proteins.
Phenophylin
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Oil in Water
Acsulfame-K - Saccharin - Cyclamate - Aspartame

7. What is the Peroxide Value a measure of?
Daminozide
Fat Oxidation
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
V=IR and P=VI or I x I x are

8. What does Acid Degree Value measure and how is it measured?
Sodium chloride reduces foam stability and sucrose improves foam stability.
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Parabens
Number of fatty acids present; mg KOH needed to saponify 1 g fat.

9. To which of the following four basic tastes are humans most sensitive? A) Bitter B) Sweet C) Sour D) Salty
A concentrate of microfibrillar proteins of fish muscle.
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.
Anthocyanins
Bitter

10. What is a polymorphism?
Blue pigment in flowers
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Chlocophyllide does not have a phytoltail
Osmosis

11. What does the acronym NPN stand for?
Bright green
Aspartic Acid and Phenylalanine
Non-protein nitrogen
Pheophytin forms

12. What chemical compound is responsible for the 'hot' principle of jalepeno peppers?
Water
Capsaicin
Carmelization and Maillard
Sodium chloride reduces foam stability and sucrose improves foam stability.

13. At what pH is benzoic acid most effective?
Sodium chloride reduces foam stability and sucrose improves foam stability.
pH 3-5
DNA transferred by cell to cell contact (bacterial sex).
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.

14. What pigment was first designated as anthocyanins?
pH below positive charge; pH at no charge; pH above negative charge
pH below positive charge; pH at no charge; pH above negative charge
Blue pigment in flowers
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.

15. Name two reasons why fats are hydrogenated.
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Chitin
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Sodium chloride reduces foam stability and sucrose improves foam stability.

16. What are the fructose contents in commercial HFCS products.
Initiation - Propagation - and Termination
.05 M HCL
45% - 52% - 90%
Sodium bicarbonate generates CO2

17. What are soluble polymers of anhydro-galacturonic acid and its esters called?
An enzyme that converts hydrogen peroxide to water plus oxygen.
Pectins
Gossypol (it is removed during the oil refining process)
Acetoin

18. What is the geometric configuration of double bonds in most natural fatty acids?
1 - 3 - 7-trimethylxanthine
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Cis
Carmelization and Maillard

19. What toxic pigment is found in cottonseed endosperm?
It explodes
Acsulfame-K - Saccharin - Cyclamate - Aspartame
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.
Gossypol (it is removed during the oil refining process)

20. What enzyme is most responsible for browning bananas?
Pectin Esterase
Ascorbic Acid and Citric Acid
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Polyphenol Oxidase

21. Name three effects of protein denaturation.
Plasmids
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Chlocophyllide does not have a phytoltail
Speed of Light

22. What is Carboxy-methyl cellulose often used for?
Thickener in foods
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Osmosis

23. S-(1-propenyl)-L-cysteine sulfoxide is the chemical precursor to the major flavor compounds In what foodstuff?
Covalent (strongest) and Hydrophobic (Weakest)
Onions ( or leeks)
Pectin Esterase
Thermus Aqauticus

24. What does the 'c' stand for in the equation E=mc2?
Speed of Light
An enzyme that converts hydrogen peroxide to water plus oxygen.
Polyphenol Oxidase
Water

25. Contains the lowest content of water
Anthocyanins
Whole Milk
Capsaicin
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.

26. What is the common name for 9 12 - cis-cis-octa dienoic acid?
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.
Non-protein nitrogen
Degradation of protein and production of acid from sugar at the same time.
Linoleic Acid

27. If oxygen attacks an unsaturated fatty acids at the double bond What is the resultant product?
Pheophytin forms
Microorganisms are very versatile - MO's can be altered by mutations or genetic engineering to produce a greater quantity of enzyme or different enzymes - recovery of enzymes is often easy - readily available - high rate of growth and enzyme producti
Two aldehydes
Acetoin

28. What is the protein efficiency ratio (PER) of casein?
D: None of the above
2.5
.05
Pectin Esterase - Polygalacturonase - Pectin Layase

29. What does the acronym NPN stand for?
Non-protein nitrogen
Polyphenol Oxidase
Primary butyric acid also caproic acid.
Primary butyric acid also caproic acid.

30. Alar is the trade name for what chemical compound?
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Chitin
Daminozide
Pectin methyl esterase or galacturonase

31. How do sodium chloride and sucrose affect foam stability?
Sodium chloride reduces foam stability and sucrose improves foam stability.
An enzyme that converts hydrogen peroxide to water plus oxygen.
Polyphenol Oxidase
Cis

32. What ketohexose is most significant to food chemists?
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Fructose
Glycosides of anthocyanidins

33. How do sodium chloride and sucrose affect foam stability?
Pectin Esterase
Sweet - Salty - Sour - and Bitter
Anomeric
Sodium chloride reduces foam stability and sucrose improves foam stability.

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

35. What does HLB stand for and What does a high and low HLB value indicate?
Thamautin
Water
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.

36. What is the major color compound in tomatoes?
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Lycopenes
Ammonia - Water - Carbon Dioxide
20 carbons and 4 double bonds

37. What is acid proteolysis?
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Degradation of protein and production of acid from sugar at the same time.
Yellow
Lycopenes

38. What metabolic end product does the Voges-Proskauer test detect?
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Lipid oxidation
Acetoin
Bright green

39. What does Reichert-Meissert Number measure?
Emulsification
Primary butyric acid also caproic acid.
Oil in Water
Ascorbic Acid and Citric Acid

40. Name 5 chelating agents used in the food industry.
Browning of freshly cut surfaces of fruits and vegetables.
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
A concentrate of microfibrillar proteins of fish muscle.
Number of fatty acids present; mg KOH needed to saponify 1 g fat.

41. Define molarity molality - and normality.
Plasmids
Initiation - Propagation - and Termination
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
1 - 3 - 7-trimethylxanthine

42. What are proteins which are soluble in 50-80% ethanol known as?
Prolamines
Initiation - Propagation - Termination
Sucrose
45% - 52% - 90%

43. 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
No
D: None of the above
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
DNA transferred by cell to cell contact (bacterial sex).

44. What are the four basic flavors perceived by the tongue?
Racemic Mixture
Sweet - Salty - Sour - and Bitter
Yellow
V=IR and P=VI or I x I x are

45. What is surimi?
Arachidonic Acid
A concentrate of microfibrillar proteins of fish muscle.
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
No

46. Name three nonpolar polar - and charged amino acids.
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Whole Milk
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.

47. Name 3 factors influencing the consistency of commercial fats.
Prolamines
Tryptophan
.05
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.

48. Name a naturally occurring protein sweetener.
Thamautin
Linoleic Acid
Polyphenols
Lamellar; Hexagonal I - II; Cubic

49. What does MSG stand for?
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Polyphenol Oxidase
Yes
Monosodium Glutamate

50. In what food is butyric acid typically found?
Anthocyanins
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Milk
.05