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 a polymorphism?
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Sodium bicarbonate generates CO2
Fatty Acid (Ester linked) to Fatty Alcohol
Sucrose

2. What is the main class of color compounds found in raspberries?
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Anthocyanins
Aspartic Acid and Phenylalanine
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.

3. Name two enzymes that are involved in softening fruits.
Pectin Esterase - Polygalacturonase - Pectin Layase
Speed of Light
Nucleation or crystal formation and crystal growth.
Yes

4. What are colloids that are stabilized by a layer of solvation called?
Negative log of the hydrogen concentration (mol/l).
45% - 52% - 90%
Emulsoids
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

5. What two types of compounds are joined with an ester bond to make a wax?
Lamellar; Hexagonal I - II; Cubic
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Water
Fatty Acid and Alcohol

6. What is the Peroxide Value a measure of?
Fat Oxidation
Thermus Aqauticus
Phenophylin
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants

7. What is Ohm's Law and What is Power Equation?
V=IR and P=VI or I x I x are
They act as catalysts - speeding the polymerization of acrylamide.
Ascorbic Acid and Citric Acid
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.

8. What compounds oxidize to form brown color in fruits and vegetables?
Parabens
Polyphenols
Monosodium Glutamate
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.

9. What is the protein efficiency ratio (PER) of casein?
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Lysine - Arginine - and Histidine
2.5
RNA transcribed to DNA

10. How can a molecular weight of protein - DNA - and RNA be determined?
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Emulsification
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)

11. To which of the following four basic tastes are humans most sensitive? A) Bitter B) Sweet C) Sour D) Salty
Bitter
Aspartic Acid and Phenylalanine
20 carbons and 4 double bonds
Aspartic Acid and Phenylalanine

12. What kinds of food emulsions are? (1) Butter (2) Mayonnaise(3) Milk
1 - 3 - 7-trimethylxanthine
Pectins
Troponins and Tropomyosin
Butter= water in oil Mayonnaise= oil in water Milk= oil in water

13. Peptide bond formation results in the formation of what secondary compound?
Water
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.
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Two aldehydes

14. What is the enzyme that softens tomatoes?
Gossypol (it is removed during the oil refining process)
Pectin Esterase
Fatty Acid and Alcohol
Daminozide

15. Which will be coldest at its freezing point: 1M dispersion of amylose 1M solution of NaCl - distilled water - or 1M solution of sucrose?
Water
Sucrose
Oil in Water
NaCl (it dissociated to a 2M solution)

16. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
Water
ERH=100 x Aw
Polyphenoloxidase
Olive Green

17. What is the major color compound in tomatoes?
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Lycopenes
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Osmosis

18. Contains the lowest content of water
Yes
Sweet - Salty - Sour - and Bitter
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Whole Milk

19. 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
Browning of freshly cut surfaces of fruits and vegetables.
Monosodium Glutamate
.05
Fat Oxidation

20. Does kosmotrophil ion discourage water structure?
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Nucleation or crystal formation and crystal growth.
No
D: None of the above

21. What is surimi?
A concentrate of microfibrillar proteins of fish muscle.
Sucrose
Phenylketonuria
Parabens

22. Alar is the trade name for what chemical compound?
Daminozide
Glycosides of anthocyanidins
Chlocophyllide does not have a phytoltail
Linoleic Acid

23. What ketohexose is most significant to food chemists?
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Arachidonic Acid
Thickener in foods
Fructose

24. Name 5 chelating agents used in the food industry.
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Emulsoids
Capsaicin
Daminozide

25. At what pH is benzoic acid most effective?
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
pH 3-5
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
D: None of the above

26. What are the limiting amino acids in corn - potato - and green peas?
Non-protein nitrogen
Lamellar; Hexagonal I - II; Cubic
Monosodium Glutamate
Corn- Lysine - Potato-Methionine - Green Peas-Methionine

27. Name 3 physical agents capable of denaturing proteins.
Thamautin
Four
20 carbons and 4 double bonds
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces

28. Name three factors useful in controlling enzyme activity.
1 - 3 - 7-trimethylxanthine
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
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.
2.5

29. Name three non-nutritive sweeteners approved for use in USA?
Acetoin
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Chitin
Pectin methylesterase & polygalacturonase

30. Name two main gluten proteins.
Orange Juice
No
Lamellar; Hexagonal I - II; Cubic
Gliadins and Glutenins

31. What is the chemical nomenclature for caffeine?
Nucleation or crystal formation and crystal growth.
Carrageenan
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

32. Name one way foam stability can be assessed.
Fatty Acid and Alcohol
Thamautin
Tryptophan
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.

33. What is Carboxy-methyl cellulose often used for?
Thickener in foods
Polyphenol Oxidase
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.

34. What is the name given to a mixture of equal parts of Darel Lisomers?
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Racemic Mixture
Osmosis
Daminozide

35. 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

36. What are the four basic flavors perceived by the tongue?
Nucleation or crystal formation and crystal growth.
Sweet - Salty - Sour - and Bitter
No
They act as catalysts - speeding the polymerization of acrylamide.

37. What are the four basic flavors perceived by the tongue?
Gossypol (it is removed during the oil refining process)
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Thickener in foods
Sweet - Salty - Sour - and Bitter

38. What are the only phenols approved for use in the microbiological preservation of foods?
Anthocyanins
Degradation of protein and production of acid from sugar at the same time.
Parabens
Number of fatty acids present; mg KOH needed to saponify 1 g fat.

39. What is the structural difference between chlorophyll and chlocophyllide?
pH 3-5
Chlocophyllide does not have a phytoltail
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
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.

40. A chlorophyll molecule reacting with magnesium exhibits what shade of green?
Daminozide
Pectin Esterase - Polygalacturonase - Pectin Layase
Bright green
Emulsoids

41. What name is given to the small circular DNA molecules that carry genetic information independently of the main bacterial chromosome?
HPLC has higher pressure than FPLC
Plasmids
Troponins and Tropomyosin
Lipase

42. Q What reaction does the enzyme 'reverse transcriptase' catalyze?
RNA transcribed to DNA
Bright green
They act as catalysts - speeding the polymerization of acrylamide.
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.

43. During freezing What are the two stages in the crystallization process?
Gossypol (it is removed during the oil refining process)
HPLC has higher pressure than FPLC
Nucleation or crystal formation and crystal growth.
Carrageenan

44. What are the fructose contents in commercial HFCS products.
45% - 52% - 90%
Cis
Fatty Acid (Ester linked) to Fatty Alcohol
HPLC has higher pressure than FPLC

45. What enzyme is most responsible for browning bananas?
Polyphenol Oxidase
Thermus Aqauticus
Covalent (strongest) and Hydrophobic (Weakest)
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants

46. What is the enzyme that softens tomatoes?
Phenylketonuria
2.5
Pectin Esterase
ERH=100 x Aw

47. What are proteins which are soluble in 50-80% ethanol known as?
Pheophytin forms
Monosodium Glutamate
Plasmids
Prolamines

48. If oxygen attacks an unsaturated fatty acids at the double bond What is the resultant product?
2.5
Two aldehydes
Fructose
Lipid oxidation

49. In polyacrylamide gel electrophoresis (PAGE) what purpose do ammonium persulfates (APS) and TEMED serve?
Daminozide
They act as catalysts - speeding the polymerization of acrylamide.
Erythorbic Acid
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.

50. What pigment was first designated as anthocyanins?
Blue pigment in flowers
Carmelization and Maillard
Nucleation or crystal formation and crystal growth.
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.