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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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1. Name three nonpolar polar - and charged amino acids.
Pectin Esterase - Polygalacturonase - Pectin Layase
.05
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Fat Oxidation

2. What is an isomer that is cheaper than Vitamin C?
Aspartic Acid and Phenylalanine
Erythorbic Acid
Ammonia - Water - Carbon Dioxide
D: None of the above

3. What is acid proteolysis?
Degradation of protein and production of acid from sugar at the same time.
Sodium chloride reduces foam stability and sucrose improves foam stability.
Plasmids
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.

4. Name two main gluten proteins.
Plasmids
Gliadins and Glutenins
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Corn- Lysine - Potato-Methionine - Green Peas-Methionine

5. What does the iodine value measure and how is it measured?
Gliadins and Glutenins
Sucrose
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Lipid oxidation

6. What name is given to the small circular DNA molecules that carry genetic information independently of the main bacterial chromosome?
Lysine - Arginine - and Histidine
Plasmids
Yellow
Phenylketonuria

7. How is pH defined?
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Ammonia - Water - Carbon Dioxide
Negative log of the hydrogen concentration (mol/l).
Monosodium Glutamate

8. If oxygen attacks an unsaturated fatty acids at the double bond What is the resultant product?
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Erythorbic Acid
Two aldehydes
Chitin

9. What does the acronym NPN stand for?
45% - 52% - 90%
Sweet - Salty - Sour - and Bitter
Thermus Aqauticus
Non-protein nitrogen

10. Give one word for a carbon atom involved in hemiacetal or acetal formation.
Anomeric
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.
Polyphenol Oxidase
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.

11. What kinds of food emulsions are? (1) Butter (2) Mayonnaise(3) Milk
Troponins and Tropomyosin
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Fructose

12. Name the three positively charged amino acids.
Daminozide
Lysine - Arginine - and Histidine
Daminozide
Browning of freshly cut surfaces of fruits and vegetables.

13. At what pH is benzoic acid most effective?
1 - 3 - 7-trimethylxanthine
pH 3-5
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.
They act as catalysts - speeding the polymerization of acrylamide.

14. What pigment was first designated as anthocyanins?
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
Blue pigment in flowers
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.
Bright green

15. What effect would the addition of sodium bicarbonate have to chocolate?
Phenylketonuria
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Oil in Water
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents

16. What is Ohm's Law and What is Power Equation?
NaCl (it dissociated to a 2M solution)
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
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.

17. What happens to a bottle of wine if before you bottle it you forget to put the stuff in it that prevents it from fermenting?
Four
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Bright green
It explodes

18. What enzyme is most responsible for browning bananas?
Pectin Esterase
Milk
Anthocyanins
Polyphenol Oxidase

19. What is the name of the structural carbohydrate found in lobsters crab - shellfish - and insects?
Erythorbic Acid
Chitin
Anomeric
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

20. What is the name of the degradation compound of chlorophyll?
Phenophylin
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Sodium chloride reduces foam stability and sucrose improves foam stability.
Thermus Aqauticus

21. Contains the lowest content of water
Whole Milk
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Pectins

22. Name three effects of protein denaturation.
Pectin methylesterase & polygalacturonase
Sucrose
V=IR and P=VI or I x I x are
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.

23. Are sorbitol and mannitol sweet?
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Erythorbic 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.
Yes

24. In genetics What is conjugation?
Emulsoids
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
DNA transferred by cell to cell contact (bacterial sex).
Carmelization and Maillard

25. What two types of compounds are joined with an ester bond to make a wax?
It explodes
Fatty Acid and Alcohol
Linoleic Acid
Sodium bicarbonate generates CO2

26. Which amino acid has the greatest molecular weight: tryptophan or tyrosine?
Phenylketonuria
Thermus Aqauticus
Tryptophan
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.

27. What is surimi?
A concentrate of microfibrillar proteins of fish muscle.
The speed of a molecule is proportional to the surrounding voltage gradient.
Pectin methyl esterase or galacturonase
Carmelization and Maillard

28. Is a disaccharide
Covalent (strongest) and Hydrophobic (Weakest)
Lipid oxidation
Sucrose
Daminozide

29. What is the geometric configuration of double bonds in most natural fatty acids?
Monosodium Glutamate
Lipid oxidation
Cis
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.

30. What happens to chlorophyll on heating?
Water
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Pheophytin forms
Degradation of protein and production of acid from sugar at the same time.

31. In polyacrylamide gel electrophoresis (PAGE) what purpose do ammonium persulfates (APS) and TEMED serve?
Monosodium Glutamate
Erythorbic Acid
They act as catalysts - speeding the polymerization of acrylamide.
Nucleation or crystal formation and crystal growth.

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
Water
pH 3-5
The speed of a molecule is proportional to the surrounding voltage gradient.
Browning of freshly cut surfaces of fruits and vegetables.

33. If the absorption of a sample is being determined spectrophotometrically at 420 nm what color is the sample?
Sucrose
Thickener in foods
Yellow
Ascorbic Acid and Citric Acid

34. What is the acid present in fish oil?
Pheophytin forms
Monosodium Glutamate
Carrageenan
Arachidonic Acid

35. What compounds oxidize to form brown color in fruits and vegetables?
Glycosides of anthocyanidins
Fatty Acid (Ester linked) to Fatty Alcohol
Pectin methyl esterase or galacturonase
Polyphenols

36. What does Acid Degree Value measure and how is it measured?
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Bright green
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Carmelization and Maillard

37. Name a commonly used household chemical leavening agent and the gas it generates.
Pheophytia does not have magnesium in porphyrin ring.
Four
Sodium bicarbonate generates CO2
Anomeric

38. Does kosmotrophil ion discourage water structure?
No
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Lamellar; Hexagonal I - II; Cubic
Lysine - Arginine - and Histidine

39. What does the saponification value measure and how is it measured?
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Pectin methylesterase & polygalacturonase
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.

40. Name a commonly used household chemical leavening agent and the gas it generates.
Sodium bicarbonate generates CO2
Chitin
Thickener in foods
Sweet - Salty - Sour - and Bitter

41. What happens to a bottle of wine if before you bottle it you forget to put the stuff in it that prevents it from fermenting?
Pectins
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Gliadins and Glutenins
It explodes

42. What is catalase?
20 carbons and 4 double bonds
Thamautin
An enzyme that converts hydrogen peroxide to water plus oxygen.
Polyphenoloxidase

43. What is Carboxy-methyl cellulose often used for?
Erythorbic Acid
Thickener in foods
Carrageenan
Pectin methylesterase & polygalacturonase

44. Name three non-nutritive sweeteners approved for use in USA?
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
They act as catalysts - speeding the polymerization of acrylamide.
Anomeric
Acsulfame-K - Saccharin - Cyclamate - Aspartame

45. What are the limiting amino acids in corn - potato - and green peas?
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Polyphenoloxidase
Emulsoids
Nucleation or crystal formation and crystal growth.

46. Contains the lowest content of water
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Whole Milk
Negative log of the hydrogen concentration (mol/l).
Daminozide

47. How many carbon atoms are there in the fatty acid myristic acid?
14
Fructose
Linoleic Acid
An enzyme that converts hydrogen peroxide to water plus oxygen.

48. How does ERH relate to water activity?
Ammonia - Water - Carbon Dioxide
ERH=100 x Aw
Arachidonic Acid
Milk

49. What is the fundamental driving of electrophoresis?
V=IR and P=VI or I x I x are
Bright green
The speed of a molecule is proportional to the surrounding voltage gradient.
Degradation of protein and production of acid from sugar at the same time.

50. What is the winterization process for an oil?
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Racemic Mixture
Arachidonic Acid
Gossypol (it is removed during the oil refining process)