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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. At what pH is benzoic acid most effective?
pH 3-5
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Emulsoids
Fatty Acid and Alcohol

2. How many carbon atoms are there in the fatty acid myristic 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.
14
Anthocyanins
Pectin methyl esterase or galacturonase

3. 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.
1 - 3 - 7-trimethylxanthine
Oil in Water
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.

4. What is surimi?
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
A concentrate of microfibrillar proteins of fish muscle.
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.

5. What are colloids that are stabilized by a layer of solvation called?
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Pectin Esterase
Pectin methylesterase & polygalacturonase
Emulsoids

6. 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
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Yes
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).

7. Name two main gluten proteins.
Gliadins and Glutenins
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
Carmelization and Maillard
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)

8. Name two reasons why fats are hydrogenated.
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Pectin Esterase
Sweet - Salty - Sour - and Bitter
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.

9. What are soluble polymers of anhydro-galacturonic acid and its esters called?
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
Pectin Esterase - Polygalacturonase - Pectin Layase
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)

10. What are the limiting amino acids in corn - potato - and green peas?
Plasmids
Pectins
Fatty Acid (Ester linked) to Fatty Alcohol
Corn- Lysine - Potato-Methionine - Green Peas-Methionine

11. What are soluble polymers of anhydro-galacturonic acid and its esters called?
Emulsoids
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Pectins
.05 M HCL

12. Waxes are composed of what two basic chemical entities?
2.5
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Fatty Acid (Ester linked) to Fatty Alcohol
Sodium bicarbonate generates CO2

13. What is the major color compound in tomatoes?
Lycopenes
Bitter
Glycosides of anthocyanidins
Polyphenoloxidase

14. What charge will a protein have when the pH of its solution is below at - and above its pKa?
Emulsoids
RNA transcribed to DNA
Thermus Aqauticus
pH below positive charge; pH at no charge; pH above negative charge

15. Which two amino acids is the aspartame derived from?
Chlocophyllide does not have a phytoltail
Troponins and Tropomyosin
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Aspartic Acid and Phenylalanine

16. What two enzymes degrade pectic substances?
Sodium bicarbonate generates CO2
Pectin methylesterase & polygalacturonase
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Initiation - Propagation - Termination

17. What is the enzyme responsible for browning in apples and lettuce?
Daminozide
Polyphenol Oxidase
Ammonia - Water - Carbon Dioxide
Fat Oxidation

18. What pigment was first designated as anthocyanins?
Chlocophyllide does not have a phytoltail
Yellow
Blue pigment in flowers
DNA transferred by cell to cell contact (bacterial sex).

19. Which will be coldest at its freezing point: 1M dispersion of amylose 1M solution of NaCl - distilled water - or 1M solution of sucrose?
Polyphenols
pH 3-5
Emulsification
NaCl (it dissociated to a 2M solution)

20. Name 5 proteins with good foaming properties.
Pectin Esterase - Polygalacturonase - Pectin Layase
Negative log of the hydrogen concentration (mol/l).
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.
pH 3-5

21. What enzyme is most responsible for browning bananas?
Osmosis
Initiation - Propagation - Termination
Polyphenol Oxidase
Lysine - Arginine - and Histidine

22. 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?
Emulsoids
Non-protein nitrogen
.05 M HCL
Fatty Acid and Alcohol

23. What is the name of the structural carbohydrate found in lobsters crab - shellfish - and insects?
Covalent (strongest) and Hydrophobic (Weakest)
Pheophytin forms
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Chitin

24. What is catalase?
An enzyme that converts hydrogen peroxide to water plus oxygen.
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Nucleation or crystal formation and crystal growth.

25. 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
Sodium bicarbonate generates CO2
Capsaicin
Osmosis
D: None of the above

26. What is the structural difference between chlorophyll and chlocophyllide?
Negative log of the hydrogen concentration (mol/l).
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.
Chlocophyllide does not have a phytoltail
Daminozide

27. Which of these foods is not appropriate to this list? A) Salami B) Yogurt C) Orange Juice D) Beer
Plasmids
Capsaicin
pH 3-5
Orange Juice

28. Alar is the trade name for what chemical compound?
Yes
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Daminozide

29. What is a polymorphism?
Sucrose
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.

30. What are proteins which are soluble in 50-80% ethanol known as?
Sweet - Salty - Sour - and Bitter
Prolamines
Phenylketonuria
An enzyme that converts hydrogen peroxide to water plus oxygen.

31. What two types of compounds are joined with an ester bond to make a wax?
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
Fatty Acid and Alcohol
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
ERH=100 x Aw

32. Name 2 heat stable enzymes in food that are important to the quality of aseptic products.
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
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
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.
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.

33. How does HPLC differ from FPLC?
HPLC has higher pressure than FPLC
Lycopenes
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Sodium bicarbonate generates CO2

34. 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.
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Water
V=IR and P=VI or I x I x are

35. What is the chemical nomenclature for caffeine?
Pheophytin forms
An enzyme that converts hydrogen peroxide to water plus oxygen.
RNA transcribed to DNA
1 - 3 - 7-trimethylxanthine

36. What does Reichert-Meissert Number measure?
Gliadins and Glutenins
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Negative log of the hydrogen concentration (mol/l).
Primary butyric acid also caproic acid.

37. Name a commonly used household chemical leavening agent and the gas it generates.
Pectin methylesterase & polygalacturonase
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.
Sodium bicarbonate generates CO2
Anthocyanins

38. What are the four basic flavors perceived by the tongue?
Sweet - Salty - Sour - and Bitter
pH below positive charge; pH at no charge; pH above negative charge
Sodium chloride reduces foam stability and sucrose improves foam stability.
Acetoin

39. Name 5 chelating agents used in the food industry.
Two aldehydes
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Emulsification
.05 M HCL

40. To which of the following four basic tastes are humans most sensitive? A) Bitter B) Sweet C) Sour D) Salty
Bitter
Milk
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
Lipase

41. What is Carboxy-methyl cellulose often used for?
45% - 52% - 90%
Thickener in foods
Racemic Mixture
Anthocyanins

42. In the enzyme Taq Polymerase What does Taq stand for?
2.5
D: None of the above
Thermus Aqauticus
A concentrate of microfibrillar proteins of fish muscle.

43. What is the geometric configuration of double bonds in most natural fatty acids?
The speed of a molecule is proportional to the surrounding voltage gradient.
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Cis
Gossypol (it is removed during the oil refining process)

44. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
14
Four
Olive Green
Phenylketonuria

45. What is the geometric configuration of double bonds in most natural fatty acids?
Sodium bicarbonate generates CO2
Cis
Whole Milk
It explodes

46. How can a molecular weight of protein - DNA - and RNA be determined?
Daminozide
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Lipid oxidation
Sodium chloride reduces foam stability and sucrose improves foam stability.

47. At low water activity What is the main deteriorative concern?
Lycopenes
Lipid oxidation
Aspartic Acid and Phenylalanine
Speed of Light

48. Name three nonpolar polar - and charged amino acids.
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.
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Emulsoids
Negative log of the hydrogen concentration (mol/l).

49. Name three compounds capable of poisoning the catalyst during commercial hydrogenation.
Lycopenes
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.

50. What does the iodine value measure and how is it measured?
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
RNA transcribed to DNA
Daminozide
Thermus Aqauticus