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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. How many polypeptide chains make up an antibody?
Four
pH below positive charge; pH at no charge; pH above negative charge
Anomeric
Fat Oxidation

2. Name 3 chemical agents capable of denaturing proteins.
Initiation - Propagation - and Termination
Milk
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Anthocyanins

3. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
Linoleic Acid
pH below positive charge; pH at no charge; pH above negative charge
Olive Green
Oil in Water

4. In what food is butyric acid typically found?
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
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.
Milk

5. What is the major color compound in tomatoes?
Polyphenol Oxidase
Lycopenes
Anthocyanins
pH 3-5

6. What is Carboxy-methyl cellulose often used for?
Thickener in foods
No
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.
Onions ( or leeks)

7. What are the fructose contents in commercial HFCS products.
Thermus Aqauticus
Troponins and Tropomyosin
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
45% - 52% - 90%

8. Peptide bond formation results in the formation of what secondary compound?
Daminozide
Water
Pectin methyl esterase or galacturonase
Polyphenol Oxidase

9. A) Is the major component of most foods.B) Controls shelf-life or storage capabilityC) Regulates chemical and microbiological reactionsD) All of the above
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
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

10. What does Reichert-Meissert Number measure?
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
Primary butyric acid also caproic acid.
Bright green
45% - 52% - 90%

11. What is the fundamental driving of electrophoresis?
Fatty Acid (Ester linked) to Fatty Alcohol
Bitter
Water
The speed of a molecule is proportional to the surrounding voltage gradient.

12. During freezing What are the two stages in the crystallization process?
Pectin Esterase - Polygalacturonase - Pectin Layase
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Nucleation or crystal formation and crystal growth.
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls

13. Name 2 heat stable enzymes in food that are important to the quality of aseptic products.
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.
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
Pectin Esterase
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.

14. Name a commonly used household chemical leavening agent and the gas it generates.
Ascorbic Acid and Citric Acid
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Sodium bicarbonate generates CO2
Degradation of protein and production of acid from sugar at the same time.

15. What are the three main steps in the autooxidation of lipids?
Speed of Light
Nucleation or crystal formation and crystal growth.
HPLC has higher pressure than FPLC
Initiation - Propagation - Termination

16. What are the four basic flavors perceived by the tongue?
Negative log of the hydrogen concentration (mol/l).
Arachidonic Acid
Sweet - Salty - Sour - and Bitter
Polyphenol Oxidase

17. What is the winterization process for an oil?
Tryptophan
Capsaicin
Cis
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.

18. 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
They act as catalysts - speeding the polymerization of acrylamide.
Polyphenoloxidase
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Orange Juice

19. 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?
Pectin methyl esterase or galacturonase
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.
.05 M HCL
Anomeric

20. How many polypeptide chains make up an antibody?
Four
The speed of a molecule is proportional to the surrounding voltage gradient.
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.
Cis

21. What toxic pigment is found in cottonseed endosperm?
Browning of freshly cut surfaces of fruits and vegetables.
Gossypol (it is removed during the oil refining process)
2.5
14

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?
The speed of a molecule is proportional to the surrounding voltage gradient.
Lipid oxidation
Gliadins and Glutenins
.05 M HCL

23. What metabolic disorder prevents conversion of phenulalanine to tyrosine by normal metabolic pathways?
Pectin Esterase
Initiation - Propagation - Termination
Phenylketonuria
Gossypol (it is removed during the oil refining process)

24. Contains the lowest content of water
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Cis
Thamautin
Whole Milk

25. What are the limiting amino acids in corn - potato - and green peas?
Daminozide
Osmosis
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Cis

26. What are the fructose contents in commercial HFCS products.
Carrageenan
Pectin methyl esterase or galacturonase
45% - 52% - 90%
Carrageenan

27. 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
RNA transcribed to DNA
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Capsaicin
Yes

28. Are sorbitol and mannitol sweet?
Covalent (strongest) and Hydrophobic (Weakest)
Ascorbic Acid and Citric Acid
Yes
Fat Oxidation

29. What are colloids that are stabilized by a layer of solvation called?
Prolamines
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.
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Emulsoids

30. What is an isomer that is cheaper than Vitamin C?
Pheophytin forms
Erythorbic Acid
Whole Milk
Primary butyric acid also caproic acid.

31. What is the structural difference between chlorophyll and pheophytia?
Pheophytia does not have magnesium in porphyrin ring.
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Lamellar; Hexagonal I - II; Cubic
Nucleation or crystal formation and crystal growth.

32. Q What reaction does the enzyme 'reverse transcriptase' catalyze?
Lycopenes
20 carbons and 4 double bonds
RNA transcribed to DNA
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants

33. 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?
Sucrose
Gliadins and Glutenins
NaCl (it dissociated to a 2M solution)
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)

34. Alar is the trade name for what chemical compound?
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Daminozide
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.

35. If the absorption of a sample is being determined spectrophotometrically at 420 nm what color is the sample?
Gliadins and Glutenins
Yellow
Blue pigment in flowers
DNA transferred by cell to cell contact (bacterial sex).

36. What are two common reducing agents that break disulfide bonds in proteins?
Tryptophan
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
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)

37. What are the four basic flavors perceived by the tongue?
Acetoin
Sweet - Salty - Sour - and Bitter
RNA transcribed to DNA
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.

38. What is the enzyme responsible for browning in apples and lettuce?
Polyphenol Oxidase
Water
Speed of Light
Corn- Lysine - Potato-Methionine - Green Peas-Methionine

39. Which amino acid has the greatest molecular weight: tryptophan or tyrosine?
Carrageenan
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Tryptophan
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)

40. Is a disaccharide
Sucrose
Lycopenes
Cis
Fatty Acid (Ester linked) to Fatty Alcohol

41. Which will be coldest at its freezing point: 1M dispersion of amylose 1M solution of NaCl - distilled water - or 1M solution of sucrose?
Four
Tryptophan
NaCl (it dissociated to a 2M solution)
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents

42. What is the Peroxide Value a measure of?
Fat Oxidation
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.
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
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.

43. What are the only phenols approved for use in the microbiological preservation of foods?
Capsaicin
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Parabens
Sodium bicarbonate generates CO2

44. What is surimi?
Fatty Acid (Ester linked) to Fatty Alcohol
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
A concentrate of microfibrillar proteins of fish muscle.
Cis

45. What are proteins which are soluble in 50-80% ethanol known as?
Prolamines
Pectin Esterase - Polygalacturonase - Pectin Layase
Pectin methylesterase & polygalacturonase
Sweet - Salty - Sour - and Bitter

46. Name the two components that comprise the relaxing factor in muscle fibers.
Erythorbic Acid
Gliadins and Glutenins
Troponins and Tropomyosin
Primary butyric acid also caproic acid.

47. What is the chemical nature of anthocyanins?
Carmelization and Maillard
Glycosides of anthocyanidins
Anomeric
Two aldehydes

48. At what pH is benzoic acid most effective?
pH 3-5
Monosodium Glutamate
Pectin Esterase - Polygalacturonase - Pectin Layase
Thamautin

49. What does the acronym NPN stand for?
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Parabens
Polyphenol Oxidase
Non-protein nitrogen

50. Name 5 proteins with good foaming properties.
Initiation - Propagation - and Termination
Linoleic Acid
D: None of the above
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.