Test your basic knowledge |

Food Chemistry

Instructions:

Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can study here.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

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 the chemical nomenclature for caffeine?
Pheophytia does not have magnesium in porphyrin ring.
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.
1 - 3 - 7-trimethylxanthine
.05

2. How can a molecular weight of protein - DNA - and RNA be determined?
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
The speed of a molecule is proportional to the surrounding voltage gradient.
20 carbons and 4 double bonds
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.

3. At low water activity What is the main deteriorative concern?
Lipid oxidation
Anomeric
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Milk

4. What is surimi?
Plasmids
Sodium chloride reduces foam stability and sucrose improves foam stability.
A concentrate of microfibrillar proteins of fish muscle.
Number of fatty acids present; mg KOH needed to saponify 1 g fat.

5. What is an isomer that is cheaper than Vitamin C?
Speed of Light
Erythorbic Acid
Polyphenols
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)

6. The undesirable clarification of orange juice or tomato juice (precipitation of pulp) is caused by what enzymes?
Pectin methyl esterase or galacturonase
An enzyme that converts hydrogen peroxide to water plus oxygen.
Parabens
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.

7. In polyacrylamide gel electrophoresis (PAGE) what purpose do ammonium persulfates (APS) and TEMED serve?
Sodium bicarbonate generates CO2
They act as catalysts - speeding the polymerization of acrylamide.
Carrageenan
Ascorbic Acid and Citric Acid

8. 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?
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
20 carbons and 4 double bonds
Covalent (strongest) and Hydrophobic (Weakest)
Primary butyric acid also caproic acid.

9. Name 5 chelating agents used in the food industry.
2.5
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.

10. What is the fundamental driving of electrophoresis?
Emulsoids
pH below positive charge; pH at no charge; pH above negative charge
The speed of a molecule is proportional to the surrounding voltage gradient.
Lipase

11. Name 4 advantages of using enzymes in food processing.
.05
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
Cis
14

12. What enzyme is most responsible for browning bananas?
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.
The speed of a molecule is proportional to the surrounding voltage gradient.
Linoleic Acid
Polyphenol Oxidase

13. How do sodium chloride and sucrose affect foam stability?
2.5
Sodium chloride reduces foam stability and sucrose improves foam stability.
Bitter
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.

14. What happens to chlorophyll on heating?
Pheophytin forms
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Thermus Aqauticus
Yes

15. Give one word for a carbon atom involved in hemiacetal or acetal formation.
Racemic Mixture
Lysine - Arginine - and Histidine
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Anomeric

16. Which amino acid has the greatest molecular weight: tryptophan or tyrosine?
Tryptophan
Oil in Water
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Lamellar; Hexagonal I - II; Cubic

17. What compounds oxidize to form brown color in fruits and vegetables?
Fatty Acid and Alcohol
The speed of a molecule is proportional to the surrounding voltage gradient.
Polyphenols
Phenylketonuria

18. What is an isomer that is cheaper than Vitamin C?
Erythorbic Acid
Non-protein nitrogen
Pectin Esterase - Polygalacturonase - Pectin Layase
It explodes

19. What is surimi?
A concentrate of microfibrillar proteins of fish muscle.
Chlocophyllide does not have a phytoltail
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Degradation of protein and production of acid from sugar at the same time.

20. What metabolic end product does the Voges-Proskauer test detect?
Polyphenol Oxidase
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Acetoin
Glycosides of anthocyanidins

21. What is the geometric configuration of double bonds in most natural fatty acids?
Cis
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Initiation - Propagation - Termination
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.

22. What is the enzyme that softens tomatoes?
Pectin Esterase
Sucrose
Thermus Aqauticus
Plasmids

23. To which of the following four basic tastes are humans most sensitive? A) Bitter B) Sweet C) Sour D) Salty
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Initiation - Propagation - Termination
Bitter
Water

24. Q What reaction does the enzyme 'reverse transcriptase' catalyze?
An enzyme that converts hydrogen peroxide to water plus oxygen.
RNA transcribed to DNA
Bitter
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)

25. How many polypeptide chains make up an antibody?
Aspartic Acid and Phenylalanine
Capsaicin
.05 M HCL
Four

26. What is the structural difference between chlorophyll and pheophytia?
Pheophytia does not have magnesium in porphyrin ring.
Monosodium Glutamate
Aspartic Acid and Phenylalanine
Acsulfame-K - Saccharin - Cyclamate - Aspartame

27. Name 3 physical agents capable of denaturing proteins.
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Pectins
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
It explodes

28. What two common compounds are used together as an antioxidative system?
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Polyphenoloxidase
Ascorbic Acid and Citric Acid
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.

29. What chemical compound is responsible for the 'hot' principle of jalepeno peppers?
Linoleic Acid
Bright green
Capsaicin
Lycopenes

30. Which of the following examples of browning is enzymatic in nature? 1. Browning of sugars as a result of heating 2. Browning of freshly cut surfaces of fruits and vegetables 3. Browning of bread during toasting 4. Browning of potato chips
No
Browning of freshly cut surfaces of fruits and vegetables.
Polyphenol Oxidase
Thermus Aqauticus

31. What is the winterization process for an oil?
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Anthocyanins
Pectin methylesterase & polygalacturonase
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.

32. What are soluble polymers of anhydro-galacturonic acid and its esters called?
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Pectins
Chitin
They act as catalysts - speeding the polymerization of acrylamide.

33. What is the Peroxide Value a measure of?
Initiation - Propagation - Termination
Fat Oxidation
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
Emulsification

34. Name 3 chemical agents capable of denaturing proteins.
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Pheophytia does not have magnesium in porphyrin ring.

35. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
Olive Green
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
Polyphenols

36. What is the common name for 9 12 - cis-cis-octa dienoic acid?
Pectin Esterase
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Linoleic Acid
The speed of a molecule is proportional to the surrounding voltage gradient.

37. Name 3 reasons it is advantageous to obtain enzymes from microorganisms.

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183

38. What are the four basic flavors perceived by the tongue?
.05 M HCL
Fatty Acid (Ester linked) to Fatty Alcohol
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Sweet - Salty - Sour - and Bitter

39. What are 3 mesomorphic structures associated with lipids in the liquid state?
Negative log of the hydrogen concentration (mol/l).
Covalent (strongest) and Hydrophobic (Weakest)
Lamellar; Hexagonal I - II; Cubic
Olive Green

40. To which of the following four basic tastes are humans most sensitive? A) Bitter B) Sweet C) Sour D) Salty
Carmelization and Maillard
Bitter
Water
Daminozide

41. Food additive that could be used to prevent cocoa particles from settling in chocolate milk
Carrageenan
Thickener in foods
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
Pheophytia does not have magnesium in porphyrin ring.

42. Contains the lowest content of water
Ammonia - Water - Carbon Dioxide
Whole Milk
Troponins and Tropomyosin
Daminozide

43. How does HPLC differ from FPLC?
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
HPLC has higher pressure than FPLC
Emulsification
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.

44. What is the geometric configuration of double bonds in most natural fatty acids?
Cis
An enzyme that converts hydrogen peroxide to water plus oxygen.
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.
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.

45. How does ERH relate to water activity?
ERH=100 x Aw
Milk
Pectins
pH below positive charge; pH at no charge; pH above negative charge

46. What two types of compounds are joined with an ester bond to make a wax?
Fatty Acid and Alcohol
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Pectin Esterase - Polygalacturonase - Pectin Layase
Yellow

47. Name two reasons why fats are hydrogenated.
Lamellar; Hexagonal I - II; Cubic
Daminozide
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Lipid oxidation

48. Name a naturally occurring protein sweetener.
Thamautin
Tryptophan
Two aldehydes
Chlocophyllide does not have a phytoltail

49. What are colloids that are stabilized by a layer of solvation called?
Pectins
Emulsoids
pH 3-5
A concentrate of microfibrillar proteins of fish muscle.

50. What are the three stages of oxidative rancidity?
Initiation - Propagation - and Termination
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Chitin
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)