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. Name 3 factors influencing the rate of lipid oxidation in foods.
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Gliadins and Glutenins
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Polyphenols

2. What happens to a bottle of wine if before you bottle it you forget to put the stuff in it that prevents it from fermenting?
Thermus Aqauticus
HPLC has higher pressure than FPLC
It explodes
Browning of freshly cut surfaces of fruits and vegetables.

3. Name two enzymes that are involved in softening fruits.
Pectin Esterase - Polygalacturonase - Pectin Layase
Carmelization and Maillard
Glycosides of anthocyanidins
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

4. What does MSG stand for?
Oil in Water
Oil in Water
45% - 52% - 90%
Monosodium Glutamate

5. What two types of compounds are joined with an ester bond to make a wax?
Cis
Fatty Acid and Alcohol
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Two aldehydes

6. During freezing What are the two stages in the crystallization process?
Nucleation or crystal formation and crystal growth.
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.
Thermus Aqauticus

7. When heated ammonium bicarbonate decomposes to form what end products?
Ammonia - Water - Carbon Dioxide
Bright green
Pheophytia does not have magnesium in porphyrin ring.
Nucleation or crystal formation and crystal growth.

8. What does the acronym NPN stand for?
Non-protein nitrogen
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Glycosides of anthocyanidins
Anomeric

9. What two enzymes degrade pectic substances?
Pectin methyl esterase or galacturonase
Phenylketonuria
Pectin methylesterase & polygalacturonase
Milk

10. Which of these foods is not appropriate to this list? A) Salami B) Yogurt C) Orange Juice D) Beer
Pectin methyl esterase or galacturonase
Orange Juice
Ascorbic Acid and Citric Acid
Non-protein nitrogen

11. At what pH is benzoic acid most effective?
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Two aldehydes
pH 3-5
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.

12. What does Reichert-Meissert Number measure?
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Primary butyric acid also caproic acid.

13. What metabolic disorder prevents conversion of phenulalanine to tyrosine by normal metabolic pathways?
Emulsoids
Tryptophan
Lycopenes
Phenylketonuria

14. Alar is the trade name for what chemical compound?
Ammonia - Water - Carbon Dioxide
Daminozide
Olive Green
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.

15. Alar is the trade name for what chemical compound?
Pectin methylesterase & polygalacturonase
Daminozide
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
D: None of the above

16. Name the most common functional property of phospholipids in food systems.
A concentrate of microfibrillar proteins of fish muscle.
Fatty Acid and Alcohol
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Emulsification

17. How many carbon atoms are there in the fatty acid myristic acid?
Plasmids
14
Thickener in foods
Polyphenol Oxidase

18. In the enzyme Taq Polymerase What does Taq stand for?
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
NaCl (it dissociated to a 2M solution)
RNA transcribed to DNA
Thermus Aqauticus

19. What effect would the addition of sodium bicarbonate have to chocolate?
Arachidonic Acid
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Olive Green
Gliadins and Glutenins

20. What kinds of food emulsions are? (1) Butter (2) Mayonnaise(3) Milk
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Lipase
Thamautin
RNA transcribed to DNA

21. What charge will a protein have when the pH of its solution is below at - and above its pKa?
Carrageenan
pH below positive charge; pH at no charge; pH above negative charge
DNA transferred by cell to cell contact (bacterial sex).
Fructose

22. What is surimi?
A concentrate of microfibrillar proteins of fish muscle.
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Fatty Acid and Alcohol
Whole Milk

23. How do sodium chloride and sucrose affect foam stability?
Sodium chloride reduces foam stability and sucrose improves foam stability.
Bright green
Anomeric
Thermus Aqauticus

24. What does MSG stand for?
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.
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Emulsoids
Monosodium Glutamate

25. Waxes are composed of what two basic chemical entities?
The speed of a molecule is proportional to the surrounding voltage gradient.
Fatty Acid (Ester linked) to Fatty Alcohol
ERH=100 x Aw
1 - 3 - 7-trimethylxanthine

26. What is the major color compound in tomatoes?
Olive Green
Blue pigment in flowers
No
Lycopenes

27. Name a naturally occurring protein sweetener.
Chitin
Orange Juice
Thamautin
Acetoin

28. What two types of compounds are joined with an ester bond to make a wax?
Fatty Acid and Alcohol
DNA transferred by cell to cell contact (bacterial sex).
Arachidonic Acid
Water

29. Which will be coldest at its freezing point: 1M dispersion of amylose 1M solution of NaCl - distilled water - or 1M solution of sucrose?
Pectins
NaCl (it dissociated to a 2M solution)
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Arachidonic Acid

30. An emulsifier with a high hydrophilic-lipophilic balance (HLB) value would promote which type of emulsion: oil in water or water in oil?
Oil in Water
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Tryptophan
Degradation of protein and production of acid from sugar at the same time.

31. What is an isomer that is cheaper than Vitamin C?
Sucrose
1 - 3 - 7-trimethylxanthine
Whole Milk
Erythorbic Acid

32. What is a polymorphism?
An enzyme that converts hydrogen peroxide to water plus oxygen.
Ascorbic Acid and Citric Acid
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.

33. What does HLB stand for and What does a high and low HLB value indicate?
Speed of Light
Thamautin
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

34. What are proteins which are soluble in 50-80% ethanol known as?
Negative log of the hydrogen concentration (mol/l).
Monosodium Glutamate
Prolamines
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.

35. If the absorption of a sample is being determined spectrophotometrically at 420 nm what color is the sample?
RNA transcribed to DNA
Yellow
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
14

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

37. What is the major color compound in tomatoes?
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Pectin Esterase - Polygalacturonase - Pectin Layase
Phenylketonuria
Lycopenes

38. Name 3 factors influencing the rate of lipid oxidation in foods.
.05 M HCL
Pectin methylesterase & polygalacturonase
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
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.

39. If the absorption of a sample is being determined spectrophotometrically at 420 nm what color is the sample?
NaCl (it dissociated to a 2M solution)
Yellow
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.

40. Name 3 factors influencing the consistency of commercial fats.
Initiation - Propagation - and Termination
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.

41. What is Ohm's Law and What is Power Equation?
V=IR and P=VI or I x I x are
A concentrate of microfibrillar proteins of fish muscle.
Pectins
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)

42. Name two main gluten proteins.
Gliadins and Glutenins
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Lamellar; Hexagonal I - II; Cubic
Water

43. What is the common name for 9 12 - cis-cis-octa dienoic acid?
Linoleic Acid
Degradation of protein and production of acid from sugar at the same time.
2.5
They act as catalysts - speeding the polymerization of acrylamide.

44. What does the 'c' stand for in the equation E=mc2?
Initiation - Propagation - and Termination
Carrageenan
Speed of Light
2.5

45. What is catalase?
An enzyme that converts hydrogen peroxide to water plus oxygen.
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Ascorbic Acid and Citric Acid
Acsulfame-K - Saccharin - Cyclamate - Aspartame

46. If oxygen attacks an unsaturated fatty acids at the double bond What is the resultant product?
It explodes
Two aldehydes
Primary butyric acid also caproic acid.
Pectin Esterase

47. What is the protein efficiency ratio (PER) of casein?
2.5
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Fructose

48. 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
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.
Orange Juice
Browning of freshly cut surfaces of fruits and vegetables.
Sweet - Salty - Sour - and Bitter

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
Water
Lamellar; Hexagonal I - II; Cubic
Nucleation or crystal formation and crystal growth.
Lycopenes

50. Name 3 chemical agents capable of denaturing proteins.
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Pectin methylesterase & polygalacturonase
Gossypol (it is removed during the oil refining process)
Osmosis