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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. What is catalase?
A concentrate of microfibrillar proteins of fish muscle.
They act as catalysts - speeding the polymerization of acrylamide.
Covalent (strongest) and Hydrophobic (Weakest)
An enzyme that converts hydrogen peroxide to water plus oxygen.

2. What are the only phenols approved for use in the microbiological preservation of foods?
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Anthocyanins
Parabens

3. What are colloids that are stabilized by a layer of solvation called?
Blue pigment in flowers
Emulsoids
Yellow
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.

4. What two enzymes degrade pectic substances?
Pectin methylesterase & polygalacturonase
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Daminozide
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.

5. What ketohexose is most significant to food chemists?
Milk
Fructose
Sodium chloride reduces foam stability and sucrose improves foam stability.
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.

6. What name is given to the small circular DNA molecules that carry genetic information independently of the main bacterial chromosome?
Plasmids
It explodes
45% - 52% - 90%
Yes

7. When heated ammonium bicarbonate decomposes to form what end products?
.05
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
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
Ammonia - Water - Carbon Dioxide

8. What is a polymorphism?
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Fatty Acid (Ester linked) to Fatty Alcohol
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)

9. What is the name of the degradation compound of chlorophyll?
Daminozide
HPLC has higher pressure than FPLC
Phenophylin
Plasmids

10. What enzyme is most responsible for browning bananas?
Polyphenol Oxidase
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Pectin Esterase - Polygalacturonase - Pectin Layase

11. What is the Peroxide Value a measure of?
Osmosis
Arachidonic Acid
Fat Oxidation
Oil in Water

12. What does Acid Degree Value measure and how is it measured?
Fatty Acid and Alcohol
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Speed of Light
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.

13. How does ERH relate to water activity?
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
ERH=100 x Aw
Milk

14. What are the primary secondary - tertiary - and quaternary structures?
Pectin methyl esterase or galacturonase
Emulsoids
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.
Fatty Acid (Ester linked) to Fatty Alcohol

15. What two common compounds are used together as an antioxidative system?
Tryptophan
Orange Juice
Ascorbic Acid and Citric Acid
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

16. Name two enzymes that are involved in softening fruits.
Pectin Esterase - Polygalacturonase - Pectin Layase
Initiation - Propagation - and Termination
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Covalent (strongest) and Hydrophobic (Weakest)

17. What chemical compound is responsible for the 'hot' principle of jalepeno peppers?
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.
Capsaicin
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.
Covalent (strongest) and Hydrophobic (Weakest)

18. What is the common name for 9 12 - cis-cis-octa dienoic acid?
Phenylketonuria
NaCl (it dissociated to a 2M solution)
Water
Linoleic Acid

19. What is the Peroxide Value a measure of?
Prolamines
Non-protein nitrogen
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Fat Oxidation

20. In polyacrylamide gel electrophoresis (PAGE) what purpose do ammonium persulfates (APS) and TEMED serve?
They act as catalysts - speeding the polymerization of acrylamide.
RNA transcribed to DNA
20 carbons and 4 double bonds
Glycosides of anthocyanidins

21. Which amino acid has the greatest molecular weight: tryptophan or tyrosine?
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
It explodes
Tryptophan
Fructose

22. Name 2 heat stable enzymes in food that are important to the quality of aseptic products.
Pectin methylesterase & polygalacturonase
Covalent (strongest) and Hydrophobic (Weakest)
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
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.

23. To which of the following four basic tastes are humans most sensitive? A) Bitter B) Sweet C) Sour D) Salty
Sodium bicarbonate generates CO2
Thamautin
Gossypol (it is removed during the oil refining process)
Bitter

24. Peptide bond formation results in the formation of what secondary compound?
Water
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Gossypol (it is removed during the oil refining process)
Polyphenoloxidase

25. Name a naturally occurring protein sweetener.
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Thamautin
Covalent (strongest) and Hydrophobic (Weakest)
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants

26. 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?
Pectin methylesterase & polygalacturonase
Yellow
Prolamines
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)

27. What are the fructose contents in commercial HFCS products.
45% - 52% - 90%
Fat Oxidation
.05
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.

28. What does the acronym NPN stand for?
They act as catalysts - speeding the polymerization of acrylamide.
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Lipase
Non-protein nitrogen

29. Which of these foods is not appropriate to this list? A) Salami B) Yogurt C) Orange Juice D) Beer
Oil in Water
An enzyme that converts hydrogen peroxide to water plus oxygen.
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Orange Juice

30. How many carbon atoms and how many double bonds are there in arachidonic acid?
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Pectins
20 carbons and 4 double bonds
Acsulfame-K - Saccharin - Cyclamate - Aspartame

31. Name 5 proteins with good foaming properties.
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.
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.
Number of fatty acids present; mg KOH needed to saponify 1 g fat.

32. Food additive that could be used to prevent cocoa particles from settling in chocolate milk
ERH=100 x Aw
Carrageenan
.05
.05

33. 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
Fructose
RNA transcribed to DNA
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
HPLC has higher pressure than FPLC

34. Which two amino acids is the aspartame derived from?
Acsulfame-K - Saccharin - Cyclamate - Aspartame
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Aspartic Acid and Phenylalanine
Chlocophyllide does not have a phytoltail

35. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Pectin methyl esterase or galacturonase
Olive Green
Emulsoids

36. What two types of compounds are joined with an ester bond to make a wax?
Fatty Acid and Alcohol
Two aldehydes
Lipid oxidation
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.

37. Name one way foam stability can be assessed.
Daminozide
Pheophytia does not have magnesium in porphyrin ring.
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.

38. What does HLB stand for and What does a high and low HLB value indicate?
1 - 3 - 7-trimethylxanthine
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.
A concentrate of microfibrillar proteins of fish muscle.
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

39. In the enzyme Taq Polymerase What does Taq stand for?
Thermus Aqauticus
Acetoin
Orange Juice
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.

40. What enzyme causes hyrolytic rancidity in milk?
Parabens
Lipase
Pheophytin forms
Water

41. What two enzymes degrade pectic substances?
Pheophytia does not have magnesium in porphyrin ring.
Sweet - Salty - Sour - and Bitter
Pectin methylesterase & polygalacturonase
D: None of the above

42. What is the name given to a mixture of equal parts of Darel Lisomers?
Water
Speed of Light
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Racemic Mixture

43. Name three effects of protein denaturation.
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
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
Water
No

44. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
Sodium bicarbonate generates CO2
Fructose
An enzyme that converts hydrogen peroxide to water plus oxygen.
Olive Green

45. Name 3 chemical agents capable of denaturing proteins.
Linoleic Acid
Nucleation or crystal formation and crystal growth.
Osmosis
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents

46. What is the name of the structural carbohydrate found in lobsters crab - shellfish - and insects?
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Monosodium Glutamate
Chitin
Bitter

47. What is a polymorphism?
A concentrate of microfibrillar proteins of fish muscle.
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Cis
Plasmids

48. What does the 'c' stand for in the equation E=mc2?
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
Speed of Light
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
No

49. A) Is the major component of most foods.B) Controls shelf-life or storage capabilityC) Regulates chemical and microbiological reactionsD) All of the above
Anthocyanins
Water
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Speed of Light

50. Name three non-nutritive sweeteners approved for use in USA?
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Initiation - Propagation - Termination