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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 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.
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Polyphenols
Lipid oxidation

2. What compounds oxidize to form brown color in fruits and vegetables?
Pectin methyl esterase or galacturonase
Polyphenols
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
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.

3. Name three non-nutritive sweeteners approved for use in USA?
Acsulfame-K - Saccharin - Cyclamate - Aspartame
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
Degradation of protein and production of acid from sugar at the same time.

4. Name the most common functional property of phospholipids in food systems.
Ammonia - Water - Carbon Dioxide
Emulsification
Olive Green
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.

5. Peptide bond formation results in the formation of what secondary compound?
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Water
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
Aspartic Acid and Phenylalanine

6. Name two main gluten proteins.
Fructose
Gliadins and Glutenins
Carmelization and Maillard
Lipase

7. What is the protein efficiency ratio (PER) of casein?
Two aldehydes
Chlocophyllide does not have a phytoltail
2.5
pH below positive charge; pH at no charge; pH above negative charge

8. Does kosmotrophil ion discourage water structure?
Lipase
RNA transcribed to DNA
No
Cis

9. What are soluble polymers of anhydro-galacturonic acid and its esters called?
Polyphenol Oxidase
Initiation - Propagation - Termination
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Pectins

10. What effect would the addition of sodium bicarbonate have to chocolate?
Pectin Esterase
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.
Sucrose

11. Which amino acid has the greatest molecular weight: tryptophan or tyrosine?
Initiation - Propagation - Termination
Bitter
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Tryptophan

12. If oxygen attacks an unsaturated fatty acids at the double bond What is the resultant product?
Lipase
ERH=100 x Aw
Two aldehydes
Lycopenes

13. What are the primary secondary - tertiary - and quaternary structures?
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Browning of freshly cut surfaces of fruits and vegetables.
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.
V=IR and P=VI or I x I x are

14. 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?
It explodes
Racemic Mixture
Tryptophan
Initiation - Propagation - and Termination

15. Name 5 chelating agents used in the food industry.
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
They act as catalysts - speeding the polymerization of acrylamide.
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Butter= water in oil Mayonnaise= oil in water Milk= oil in water

16. Name 5 proteins with good foaming properties.
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.
Racemic Mixture
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.

17. Name 5 chelating agents used in the food industry.
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Pectin methyl esterase or galacturonase
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.

18. What is surimi?
Carrageenan
A concentrate of microfibrillar proteins of fish muscle.
Tryptophan
Emulsification

19. When heated ammonium bicarbonate decomposes to form what end products?
Ammonia - Water - Carbon Dioxide
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Tryptophan
Oil in Water

20. 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
Anthocyanins
D: None of the above
Covalent (strongest) and Hydrophobic (Weakest)
Yes

21. Name a commonly used household chemical leavening agent and the gas it generates.
Sodium bicarbonate generates CO2
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.
1 - 3 - 7-trimethylxanthine
Fatty Acid and Alcohol

22. At low water activity What is the main deteriorative concern?
Polyphenol Oxidase
Erythorbic Acid
Lipid oxidation
RNA transcribed to DNA

23. What is the geometric configuration of double bonds in most natural fatty acids?
Orange Juice
Water
Water
Cis

24. What metabolic disorder prevents conversion of phenulalanine to tyrosine by normal metabolic pathways?
Glycosides of anthocyanidins
The speed of a molecule is proportional to the surrounding voltage gradient.
Phenylketonuria
Four

25. To which of the following four basic tastes are humans most sensitive? A) Bitter B) Sweet C) Sour D) Salty
Yellow
Degradation of protein and production of acid from sugar at the same time.
Emulsoids
Bitter

26. Name 3 chemical agents capable of denaturing proteins.
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Yes
Fatty Acid and Alcohol
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.

27. What toxic pigment is found in cottonseed endosperm?
Gossypol (it is removed during the oil refining process)
Yellow
D: None of the above
NaCl (it dissociated to a 2M solution)

28. Which two amino acids is the aspartame derived from?
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
Aspartic Acid and Phenylalanine
Gliadins and Glutenins
Four

29. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
Yellow
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
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.
Olive Green

30. Alar is the trade name for what chemical compound?
Phenophylin
Sucrose
Ascorbic Acid and Citric Acid
Daminozide

31. What two types of compounds are joined with an ester bond to make a wax?
Arachidonic Acid
Blue pigment in flowers
.05
Fatty Acid and Alcohol

32. Name the three positively charged amino acids.
A concentrate of microfibrillar proteins of fish muscle.
Lysine - Arginine - and Histidine
Water
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.

33. How does ERH relate to water activity?
ERH=100 x Aw
An enzyme that converts hydrogen peroxide to water plus oxygen.
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)

34. What enzyme is most responsible for browning bananas?
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Sodium bicarbonate generates CO2
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

35. What two enzymes degrade pectic substances?
Troponins and Tropomyosin
Anthocyanins
D: None of the above
Pectin methylesterase & polygalacturonase

36. What are the three main steps in the autooxidation of lipids?
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.
Arachidonic Acid
Gossypol (it is removed during the oil refining process)
Initiation - Propagation - Termination

37. A chlorophyll molecule reacting with magnesium exhibits what shade of green?
Chitin
Bright green
Yellow
Lipase

38. What is the name given to a mixture of equal parts of Darel Lisomers?
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Racemic Mixture
Gossypol (it is removed during the oil refining process)
A concentrate of microfibrillar proteins of fish muscle.

39. Name three nonpolar polar - and charged amino acids.
Daminozide
Daminozide
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)

40. What is the main class of color compounds found in raspberries?
20 carbons and 4 double bonds
Anthocyanins
Polyphenol Oxidase
Negative log of the hydrogen concentration (mol/l).

41. During freezing What are the two stages in the crystallization process?
Covalent (strongest) and Hydrophobic (Weakest)
Bitter
Nucleation or crystal formation and crystal growth.
Carrageenan

42. What enzyme causes hyrolytic rancidity in milk?
Chitin
Chlocophyllide does not have a phytoltail
Lipase
Parabens

43. The undesirable clarification of orange juice or tomato juice (precipitation of pulp) is caused by what enzymes?
HPLC has higher pressure than FPLC
Pectin methyl esterase or galacturonase
Arachidonic Acid
Lipid oxidation

44. If the absorption of a sample is being determined spectrophotometrically at 420 nm what color is the sample?
Yellow
Covalent (strongest) and Hydrophobic (Weakest)
Carrageenan
HPLC has higher pressure than FPLC

45. What charge will a protein have when the pH of its solution is below at - and above its pKa?
pH below positive charge; pH at no charge; pH above negative charge
Gossypol (it is removed during the oil refining process)
Sodium bicarbonate generates CO2
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.

46. How many carbon atoms are there in the fatty acid myristic acid?
14
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Polyphenol Oxidase
Initiation - Propagation - Termination

47. Name 3 physical agents capable of denaturing proteins.
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
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.
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.

48. In what food is butyric acid typically found?
NaCl (it dissociated to a 2M solution)
Capsaicin
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Milk

49. Name a naturally occurring protein sweetener.
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.
Ascorbic Acid and Citric Acid
Thamautin
Bitter

50. What is an isomer that is cheaper than Vitamin C?
Emulsoids
Polyphenols
Pectins
Erythorbic Acid