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Food Chemistry

Instructions:

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. What are the fructose contents in commercial HFCS products.
45% - 52% - 90%
Fat Oxidation
Lamellar; Hexagonal I - II; Cubic
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.

2. What is the chemical nature of anthocyanins?
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Glycosides of anthocyanidins
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
Anthocyanins

3. Name two non-enzymatic browning reactions.
1 - 3 - 7-trimethylxanthine
Lysine - Arginine - and Histidine
ERH=100 x Aw
Carmelization and Maillard

4. What is the major color compound in tomatoes?
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Lycopenes
Polyphenol Oxidase

5. 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
Milk
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Phenylketonuria
Lamellar; Hexagonal I - II; Cubic

6. What does MSG stand for?
Monosodium Glutamate
Gliadins and Glutenins
Polyphenol Oxidase
Chitin

7. When heated ammonium bicarbonate decomposes to form what end products?
Anthocyanins
Two aldehydes
Phenylketonuria
Ammonia - Water - Carbon Dioxide

8. What does Reichert-Meissert Number measure?
Ammonia - Water - Carbon Dioxide
Primary butyric acid also caproic acid.
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.
Pectins

9. What is an isomer that is cheaper than Vitamin C?
Onions ( or leeks)
Pectin Esterase
Polyphenoloxidase
Erythorbic Acid

10. What are 3 mesomorphic structures associated with lipids in the liquid state?
Pheophytin forms
45% - 52% - 90%
Lamellar; Hexagonal I - II; Cubic
Plasmids

11. Alar is the trade name for what chemical compound?
Lysine - Arginine - and Histidine
Daminozide
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
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

12. What does the iodine value measure and how is it measured?
Sweet - Salty - Sour - and Bitter
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Ascorbic Acid and Citric Acid

13. What does Acid Degree Value measure and how is it measured?
1 - 3 - 7-trimethylxanthine
Aspartic Acid and Phenylalanine
Negative log of the hydrogen concentration (mol/l).
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.

14. What is the protein efficiency ratio (PER) of casein?
Polyphenols
2.5
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Non-protein nitrogen

15. 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
Linoleic Acid
D: None of the above
The speed of a molecule is proportional to the surrounding voltage gradient.
Racemic Mixture

16. If oxygen attacks an unsaturated fatty acids at the double bond What is the resultant product?
Thickener in foods
Milk
Two aldehydes
1 - 3 - 7-trimethylxanthine

17. What is the name given to a mixture of equal parts of Darel Lisomers?
Acsulfame-K - Saccharin - Cyclamate - Aspartame
They act as catalysts - speeding the polymerization of acrylamide.
HPLC has higher pressure than FPLC
Racemic Mixture

18. What chemical compound is responsible for the 'hot' principle of jalepeno peppers?
Negative log of the hydrogen concentration (mol/l).
Tryptophan
Capsaicin
Phenylketonuria

19. Give one word for a carbon atom involved in hemiacetal or acetal formation.
Polyphenol Oxidase
Anomeric
2.5
Negative log of the hydrogen concentration (mol/l).

20. Is a disaccharide
Orange Juice
Sucrose
Whole Milk
Polyphenols

21. Which two amino acids is the aspartame derived from?
Thickener in foods
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Aspartic Acid and Phenylalanine
DNA transferred by cell to cell contact (bacterial sex).

22. How does HPLC differ from FPLC?
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Initiation - Propagation - Termination
HPLC has higher pressure than FPLC
Lycopenes

23. Are sorbitol and mannitol sweet?
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
Yes
Browning of freshly cut surfaces of fruits and vegetables.
Pheophytin forms

24. Name three compounds capable of poisoning the catalyst during commercial hydrogenation.
Covalent (strongest) and Hydrophobic (Weakest)
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Lysine - Arginine - and Histidine
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.

25. What are the only phenols approved for use in the microbiological preservation of foods?
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Chlocophyllide does not have a phytoltail
Parabens
Racemic Mixture

26. What is the enzyme that softens tomatoes?
Arachidonic Acid
Pectin Esterase
Polyphenol Oxidase
Prolamines

27. At what pH is benzoic acid most effective?
Initiation - Propagation - Termination
pH 3-5
Chitin
Sweet - Salty - Sour - and Bitter

28. 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
Pheophytin forms
NaCl (it dissociated to a 2M solution)
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Monosodium Glutamate

29. Name three non-nutritive sweeteners approved for use in USA?
Pectin methylesterase & polygalacturonase
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Non-protein nitrogen
Primary butyric acid also caproic acid.

30. What are the limiting amino acids in corn - potato - and green peas?
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Whole Milk
Acetoin
Nucleation or crystal formation and crystal growth.

31. Alar is the trade name for what chemical compound?
Daminozide
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Anomeric
pH 3-5

32. What does MSG stand for?
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
1 - 3 - 7-trimethylxanthine
Monosodium Glutamate
Nucleation or crystal formation and crystal growth.

33. How do sodium chloride and sucrose affect foam stability?
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Anthocyanins
Sodium chloride reduces foam stability and sucrose improves foam stability.
Pectin methyl esterase or galacturonase

34. What is catalase?
Pectin methylesterase & polygalacturonase
Water
RNA transcribed to DNA
An enzyme that converts hydrogen peroxide to water plus oxygen.

35. A chlorophyll molecule reacting with magnesium exhibits what shade of green?
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Negative log of the hydrogen concentration (mol/l).
Bright green
Pectin Esterase

36. The undesirable clarification of orange juice or tomato juice (precipitation of pulp) is caused by what enzymes?
Pectins
Two aldehydes
Pectin methyl esterase or galacturonase
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.

37. What is surimi?
A concentrate of microfibrillar proteins of fish muscle.
Fat Oxidation
Polyphenol Oxidase
Olive Green

38. What is the main class of color compounds found in raspberries?
A concentrate of microfibrillar proteins of fish muscle.
45% - 52% - 90%
Anthocyanins
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.

39. Which of these foods is not appropriate to this list? A) Salami B) Yogurt C) Orange Juice D) Beer
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Polyphenol Oxidase
Acetoin
Orange Juice

40. What is the enzyme responsible for browning in apples and lettuce?
Fat Oxidation
Polyphenol Oxidase
Pectin Esterase
Gliadins and Glutenins

41. What degradative enzyme causes browning in apples - pears - bananas - and peaches?
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.
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Polyphenoloxidase

42. A) Is the major component of most foods.B) Controls shelf-life or storage capabilityC) Regulates chemical and microbiological reactionsD) All of the above
Carmelization and Maillard
Water
Pectin methylesterase & polygalacturonase
Aspartic Acid and Phenylalanine

43. What kinds of food emulsions are? (1) Butter (2) Mayonnaise(3) Milk
Browning of freshly cut surfaces of fruits and vegetables.
.05
Primary butyric acid also caproic acid.
Butter= water in oil Mayonnaise= oil in water Milk= oil in water

44. Name 3 factors influencing the rate of lipid oxidation in foods.
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Thermus Aqauticus
.05 M HCL
Water

45. What does HLB stand for and What does a high and low HLB value indicate?
Bright green
They act as catalysts - speeding the polymerization of acrylamide.
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.
Arachidonic Acid

46. Name 3 chemical agents capable of denaturing proteins.
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Milk

47. What is the major color compound in tomatoes?
14
Lycopenes
An enzyme that converts hydrogen peroxide to water plus oxygen.
Bitter

48. Name one way foam stability can be assessed.
It explodes
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.
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Thamautin

49. What is the Peroxide Value a measure of?
Fat Oxidation
They act as catalysts - speeding the polymerization of acrylamide.
Nucleation or crystal formation and crystal growth.
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces

50. What is a polymorphism?
Osmosis
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Lamellar; Hexagonal I - II; Cubic
DNA transferred by cell to cell contact (bacterial sex).