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Food Chemistry

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Answer 50 questions in 15 minutes.
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1. Name 3 factors influencing the consistency of commercial fats.
They act as catalysts - speeding the polymerization of acrylamide.
D: None of the above
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
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

2. Name a naturally occurring protein sweetener.
Water
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Blue pigment in flowers
Thamautin

3. During freezing What are the two stages in the crystallization process?
Thamautin
Nucleation or crystal formation and crystal growth.
Milk
Acsulfame-K - Saccharin - Cyclamate - Aspartame

4. What does the acronym NPN stand for?
Anthocyanins
Non-protein nitrogen
Polyphenoloxidase
Yes

5. At what pH is benzoic acid most effective?
They act as catalysts - speeding the polymerization of acrylamide.
An enzyme that converts hydrogen peroxide to water plus oxygen.
pH 3-5
Pectin methyl esterase or galacturonase

6. What does the 'c' stand for in the equation E=mc2?
Lipase
Sucrose
Speed of Light
Cis

7. 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?
Emulsification
Orange Juice
Daminozide
.05 M HCL

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

9. What is Carboxy-methyl cellulose often used for?
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Thickener in foods
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

10. 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?
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Daminozide
Pheophytia does not have magnesium in porphyrin ring.
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)

11. 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?
Primary butyric acid also caproic acid.
.05 M HCL
2.5
Pectins

12. What are the limiting amino acids in corn - potato - and green peas?
Milk
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.

13. What is the name of the structural carbohydrate found in lobsters crab - shellfish - and insects?
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.
Lipid oxidation
Prolamines
Chitin

14. How does ERH relate to water activity?
ERH=100 x Aw
Lamellar; Hexagonal I - II; Cubic
Bright green
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.

15. What are the limiting amino acids in corn - potato - and green peas?
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Ascorbic Acid and Citric Acid
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.

16. What are the three stages of oxidative rancidity?
Arachidonic Acid
Initiation - Propagation - and Termination
Browning of freshly cut surfaces of fruits and vegetables.
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.

17. Food additive that could be used to prevent cocoa particles from settling in chocolate milk
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Four
Carrageenan
Pectin methylesterase & polygalacturonase

18. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
Olive Green
Speed of Light
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.
Lycopenes

19. How does HPLC differ from FPLC?
Fat Oxidation
HPLC has higher pressure than FPLC
NaCl (it dissociated to a 2M solution)
Phenophylin

20. What is the protein efficiency ratio (PER) of casein?
Speed of Light
2.5
They act as catalysts - speeding the polymerization of acrylamide.
Ammonia - Water - Carbon Dioxide

21. Name 5 proteins with good foaming properties.
ERH=100 x Aw
Lipid oxidation
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

22. How many carbon atoms are there in the fatty acid myristic acid?
Pectin Esterase
HPLC has higher pressure than FPLC
14
Orange Juice

23. In what food is butyric acid typically found?
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Lipid oxidation
Bitter
Milk

24. 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.
D: None of the above
Ammonia - Water - Carbon Dioxide
Troponins and Tropomyosin

25. What is the Peroxide Value a measure of?
Fat Oxidation
Lamellar; Hexagonal I - II; Cubic
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
A concentrate of microfibrillar proteins of fish muscle.

26. Alar is the trade name for what chemical compound?
Nucleation or crystal formation and crystal growth.
Daminozide
Water
Initiation - Propagation - and Termination

27. Does kosmotrophil ion discourage water structure?
Chitin
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
No
Sweet - Salty - Sour - and Bitter

28. What is the movement of molecules through a semi permeable membrane from a region of low to high solute concentration called?
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Osmosis
Non-protein nitrogen
Cis

29. Name a commonly used household chemical leavening agent and the gas it generates.
Sodium bicarbonate generates CO2
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Degradation of protein and production of acid from sugar at the same time.
Cis

30. Name 3 factors influencing the rate of lipid oxidation in foods.
Browning of freshly cut surfaces of fruits and vegetables.
45% - 52% - 90%
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
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.

31. What are the four basic flavors perceived by the tongue?
Sweet - Salty - Sour - and Bitter
They act as catalysts - speeding the polymerization of acrylamide.
Polyphenoloxidase
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.

32. What are the fructose contents in commercial HFCS products.
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
1 - 3 - 7-trimethylxanthine
45% - 52% - 90%
RNA transcribed to DNA

33. What degradative enzyme causes browning in apples - pears - bananas - and peaches?
Ammonia - Water - Carbon Dioxide
Polyphenoloxidase
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
A concentrate of microfibrillar proteins of fish muscle.

34. What are the primary secondary - tertiary - and quaternary structures?
It explodes
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.
Water
45% - 52% - 90%

35. Name three factors useful in controlling enzyme activity.
2.5
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Phenylketonuria
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls

36. Give one word for a carbon atom involved in hemiacetal or acetal formation.
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
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.

37. If oxygen attacks an unsaturated fatty acids at the double bond What is the resultant product?
Yellow
Negative log of the hydrogen concentration (mol/l).
Two aldehydes
Whole Milk

38. Is a disaccharide
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Sucrose
Chlocophyllide does not have a phytoltail
Troponins and Tropomyosin

39. A chlorophyll molecule reacting with magnesium exhibits what shade of green?
Polyphenols
Bright green
Sweet - Salty - Sour - and Bitter
Butter= water in oil Mayonnaise= oil in water Milk= oil in water

40. Give one word for a carbon atom involved in hemiacetal or acetal formation.
Phenophylin
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Anomeric
Yellow

41. In the enzyme Taq Polymerase What does Taq stand for?
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
DNA transferred by cell to cell contact (bacterial sex).
Thamautin
Thermus Aqauticus

42. What is the structural difference between chlorophyll and chlocophyllide?
Carmelization and Maillard
Chlocophyllide does not have a phytoltail
Covalent (strongest) and Hydrophobic (Weakest)
Primary butyric acid also caproic acid.

43. What is an isomer that is cheaper than Vitamin C?
Erythorbic Acid
45% - 52% - 90%
Sweet - Salty - Sour - and Bitter
Acetoin

44. 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?
Browning of freshly cut surfaces of fruits and vegetables.
Osmosis
It explodes
Fat Oxidation

45. 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
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Polyphenol Oxidase
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
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

46. If the absorption of a sample is being determined spectrophotometrically at 420 nm what color is the sample?
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Yellow
Sweet - Salty - Sour - and Bitter

47. Which two amino acids is the aspartame derived from?
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Aspartic Acid and Phenylalanine
Lipid oxidation
DNA transferred by cell to cell contact (bacterial sex).

48. S-(1-propenyl)-L-cysteine sulfoxide is the chemical precursor to the major flavor compounds In what foodstuff?
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Fructose
Onions ( or leeks)
Corn- Lysine - Potato-Methionine - Green Peas-Methionine

49. What two types of compounds are joined with an ester bond to make a wax?
Fatty Acid and Alcohol
Lipase
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Pheophytin forms

50. Name the three positively charged amino acids.
Lycopenes
Linoleic Acid
Lysine - Arginine - and Histidine
1 - 3 - 7-trimethylxanthine