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 main class of color compounds found in raspberries?
Sodium chloride reduces foam stability and sucrose improves foam stability.
V=IR and P=VI or I x I x are
Anthocyanins
Fatty Acid and Alcohol

2. What is the structural difference between chlorophyll and pheophytia?
.05
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Pheophytia does not have magnesium in porphyrin ring.
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.

3. What pigment was first designated as anthocyanins?
Parabens
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 amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Blue pigment in flowers

4. Food additive that could be used to prevent cocoa particles from settling in chocolate milk
Carrageenan
Oil in Water
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
D: None of the above

5. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
Olive Green
Chlocophyllide does not have a phytoltail
Sweet - Salty - Sour - and Bitter
Pheophytia does not have magnesium in porphyrin ring.

6. What is the movement of molecules through a semi permeable membrane from a region of low to high solute concentration called?
Olive Green
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Osmosis
Aspartic Acid and Phenylalanine

7. What enzyme is most responsible for browning bananas?
Anomeric
2.5
Osmosis
Polyphenol Oxidase

8. What are the limiting amino acids in corn - potato - and green peas?
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
V=IR and P=VI or I x I x are
Initiation - Propagation - and Termination
20 carbons and 4 double bonds

9. An emulsifier with a high hydrophilic-lipophilic balance (HLB) value would promote which type of emulsion: oil in water or water in oil?
Blue pigment in flowers
Nucleation or crystal formation and crystal growth.
Oil in Water
Initiation - Propagation - and Termination

10. 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?
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Arachidonic Acid
.05 M HCL
Cis

11. If the absorption of a sample is being determined spectrophotometrically at 420 nm what color is the sample?
RNA transcribed to DNA
Phenophylin
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Yellow

12. Which two amino acids is the aspartame derived from?
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
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Aspartic Acid and Phenylalanine
Primary butyric acid also caproic acid.

13. What degradative enzyme causes browning in apples - pears - bananas - and peaches?
Prolamines
D: None of the above
Polyphenoloxidase
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.

14. What are the fructose contents in commercial HFCS products.
1 - 3 - 7-trimethylxanthine
Carrageenan
Two aldehydes
45% - 52% - 90%

15. What degradative enzyme causes browning in apples - pears - bananas - and peaches?
Polyphenoloxidase
Fatty Acid (Ester linked) to Fatty Alcohol
Negative log of the hydrogen concentration (mol/l).
Capsaicin

16. What is the fundamental driving of electrophoresis?
The speed of a molecule is proportional to the surrounding voltage gradient.
It explodes
Four
Parabens

17. What is the name given to a mixture of equal parts of Darel Lisomers?
Racemic Mixture
Pectins
Chlocophyllide does not have a phytoltail
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls

18. What is the major color compound in tomatoes?
Lycopenes
Initiation - Propagation - Termination
Thermus Aqauticus
Oil in Water

19. Name 3 factors influencing the consistency of commercial fats.
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Emulsification
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.

20. What are soluble polymers of anhydro-galacturonic acid and its esters called?
Cis
Pectins
Racemic Mixture
Polyphenoloxidase

21. 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.
Pectin Esterase - Polygalacturonase - Pectin Layase
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.

22. What two enzymes degrade pectic substances?
Anomeric
Thamautin
Emulsoids
Pectin methylesterase & polygalacturonase

23. Name the three positively charged amino acids.
Lysine - Arginine - and Histidine
pH 3-5
Thickener in foods
20 carbons and 4 double bonds

24. Name three effects of protein denaturation.
Carmelization and Maillard
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Anomeric
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.

25. What is the chemical nature of anthocyanins?
Glycosides of anthocyanidins
Polyphenols
.05 M HCL
Tryptophan

26. Name two enzymes that are involved in softening fruits.
V=IR and P=VI or I x I x are
Thickener in foods
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Pectin Esterase - Polygalacturonase - Pectin Layase

27. Does kosmotrophil ion discourage water structure?
No
Aspartic Acid and Phenylalanine
Erythorbic Acid
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.

28. What is the name of the degradation compound of chlorophyll?
Phenophylin
Thermus Aqauticus
Fatty Acid (Ester linked) to Fatty Alcohol
Polyphenol Oxidase

29. How can a molecular weight of protein - DNA - and RNA be determined?
ERH=100 x Aw
Blue pigment in flowers
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.

30. What are the three main steps in the autooxidation of lipids?
Initiation - Propagation - Termination
Capsaicin
V=IR and P=VI or I x I x are
Yes

31. What does Acid Degree Value measure and how is it measured?
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Lycopenes
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Linoleic Acid

32. What is the name of the degradation compound of chlorophyll?
.05 M HCL
Phenophylin
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Water

33. Name three factors useful in controlling enzyme activity.
Carrageenan
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
pH below positive charge; pH at no charge; pH above negative charge

34. What does MSG stand for?
Gliadins and Glutenins
A concentrate of microfibrillar proteins of fish muscle.
Monosodium Glutamate
Anomeric

35. Name 2 heat stable enzymes in food that are important to the quality of aseptic products.
Fatty Acid and Alcohol
2.5
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
1 - 3 - 7-trimethylxanthine

36. What is the chemical nature of anthocyanins?
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.
Acetoin
Glycosides of anthocyanidins

37. What metabolic disorder prevents conversion of phenulalanine to tyrosine by normal metabolic pathways?
Pheophytia does not have magnesium in porphyrin ring.
Monosodium Glutamate
Phenylketonuria
Oil in Water

38. What is the name of the structural carbohydrate found in lobsters crab - shellfish - and insects?
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Chitin
D: None of the above

39. In genetics What is conjugation?
ERH=100 x Aw
45% - 52% - 90%
DNA transferred by cell to cell contact (bacterial sex).
Covalent (strongest) and Hydrophobic (Weakest)

40. What are proteins which are soluble in 50-80% ethanol known as?
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
A concentrate of microfibrillar proteins of fish muscle.
Prolamines
Racemic Mixture

41. During freezing What are the two stages in the crystallization process?
Glycosides of anthocyanidins
Nucleation or crystal formation and crystal growth.
20 carbons and 4 double bonds
Polyphenoloxidase

42. What is the major color compound in tomatoes?
Lycopenes
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.
Chitin
Milk

43. What is the enzyme that softens tomatoes?
Pectin Esterase
Water
HPLC has higher pressure than FPLC
Anomeric

44. What kinds of food emulsions are? (1) Butter (2) Mayonnaise(3) Milk
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Pectin Esterase
Monosodium Glutamate

45. What are proteins which are soluble in 50-80% ethanol known as?
1 - 3 - 7-trimethylxanthine
Water
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
Prolamines

46. Define molarity molality - and normality.
Pectins
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Two aldehydes
Speed of Light

47. What two enzymes degrade pectic substances?
Bright green
Phenophylin
20 carbons and 4 double bonds
Pectin methylesterase & polygalacturonase

48. Name one way foam stability can be assessed.
Polyphenols
Ammonia - Water - Carbon Dioxide
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.
20 carbons and 4 double bonds

49. Name three factors useful in controlling enzyme activity.
Glycosides of anthocyanidins
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Milk
Number of fatty acids present; mg KOH needed to saponify 1 g fat.

50. What are the fructose contents in commercial HFCS products.
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
45% - 52% - 90%
Negative log of the hydrogen concentration (mol/l).
Bitter