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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. What is the common name for 9 12 - cis-cis-octa dienoic acid?
Linoleic Acid
1 - 3 - 7-trimethylxanthine
Ascorbic Acid and Citric Acid
Aspartic Acid and Phenylalanine

2. What does the saponification value measure and how is it measured?
Prolamines
An enzyme that converts hydrogen peroxide to water plus oxygen.
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Whole Milk

3. What is Ohm's Law and What is Power Equation?
Anomeric
20 carbons and 4 double bonds
V=IR and P=VI or I x I x are
Carmelization and Maillard

4. The undesirable clarification of orange juice or tomato juice (precipitation of pulp) is caused by what enzymes?
Pectin methyl esterase or galacturonase
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
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
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces

5. 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?
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.
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Monosodium Glutamate
Initiation - Propagation - and Termination

6. Name 2 heat stable enzymes in food that are important to the quality of aseptic products.
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Troponins and Tropomyosin
1 - 3 - 7-trimethylxanthine

7. Name three non-nutritive sweeteners approved for use in USA?
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Yellow
Troponins and Tropomyosin

8. What is the name of the degradation compound of chlorophyll?
Fat Oxidation
Phenophylin
A concentrate of microfibrillar proteins of fish muscle.
NaCl (it dissociated to a 2M solution)

9. What enzyme causes hyrolytic rancidity in milk?
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.
Lipase
Sweet - Salty - Sour - and Bitter

10. Are sorbitol and mannitol sweet?
Racemic Mixture
14
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Yes

11. What is the chemical nomenclature for caffeine?
Gliadins and Glutenins
Chitin
Polyphenols
1 - 3 - 7-trimethylxanthine

12. How many carbon atoms and how many double bonds are there in arachidonic acid?
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
20 carbons and 4 double bonds
Gossypol (it is removed during the oil refining process)
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.

13. In the enzyme Taq Polymerase What does Taq stand for?
Thickener in foods
Thermus Aqauticus
Thickener in foods
1 - 3 - 7-trimethylxanthine

14. Name a commonly used household chemical leavening agent and the gas it generates.
Fat Oxidation
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
D: None of the above
Sodium bicarbonate generates CO2

15. What name is given to the small circular DNA molecules that carry genetic information independently of the main bacterial chromosome?
Erythorbic Acid
45% - 52% - 90%
Plasmids
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)

16. What is Carboxy-methyl cellulose often used for?
Chlocophyllide does not have a phytoltail
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Phenylketonuria
Thickener in foods

17. Food additive that could be used to prevent cocoa particles from settling in chocolate milk
Carrageenan
.05
It explodes
Fatty Acid and Alcohol

18. Name two non-enzymatic browning reactions.
It explodes
Orange Juice
Carmelization and Maillard
Pectins

19. A) Is the major component of most foods.B) Controls shelf-life or storage capabilityC) Regulates chemical and microbiological reactionsD) All of the above
Polyphenoloxidase
HPLC has higher pressure than FPLC
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Water

20. What are the fructose contents in commercial HFCS products.
Negative log of the hydrogen concentration (mol/l).
45% - 52% - 90%
Onions ( or leeks)
Osmosis

21. What does the 'c' stand for in the equation E=mc2?
RNA transcribed to DNA
Speed of Light
Whole Milk
Water

22. Name one way foam stability can be assessed.
Blue pigment in flowers
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.
Degradation of protein and production of acid from sugar at the same time.

23. What is the name given to a mixture of equal parts of Darel Lisomers?
Racemic Mixture
Polyphenoloxidase
Chitin
Phenylketonuria

24. If the absorption of a sample is being determined spectrophotometrically at 420 nm what color is the sample?
Yellow
Negative log of the hydrogen concentration (mol/l).
Ammonia - Water - Carbon Dioxide
1 - 3 - 7-trimethylxanthine

25. When heated ammonium bicarbonate decomposes to form what end products?
They act as catalysts - speeding the polymerization of acrylamide.
Chlocophyllide does not have a phytoltail
Ammonia - Water - Carbon Dioxide
Yellow

26. What does MSG stand for?
Tryptophan
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Monosodium Glutamate

27. What is the geometric configuration of double bonds in most natural fatty acids?
Cis
Lamellar; Hexagonal I - II; Cubic
NaCl (it dissociated to a 2M solution)
.05 M HCL

28. What does HLB stand for and What does a high and low HLB value indicate?
Capsaicin
Bright green
Fat Oxidation
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.

29. Name 3 factors influencing the consistency of commercial fats.
Orange Juice
NaCl (it dissociated to a 2M solution)
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Capsaicin

30. 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?
Daminozide
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
It explodes
An enzyme that converts hydrogen peroxide to water plus oxygen.

31. S-(1-propenyl)-L-cysteine sulfoxide is the chemical precursor to the major flavor compounds In what foodstuff?
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Onions ( or leeks)
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Gliadins and Glutenins

32. What is the protein efficiency ratio (PER) of casein?
2.5
Pectin Esterase
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.
Erythorbic Acid

33. How does ERH relate to water activity?
RNA transcribed to DNA
Racemic Mixture
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
ERH=100 x Aw

34. Name three effects of protein denaturation.
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Lycopenes
Four
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.

35. Name 3 physical agents capable of denaturing proteins.
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Thamautin
20 carbons and 4 double bonds

36. What is the winterization process for an oil?
Initiation - Propagation - and Termination
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
NaCl (it dissociated to a 2M solution)
Whole Milk

37. What is the name of the degradation compound of chlorophyll?
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Phenophylin
Ammonia - Water - Carbon Dioxide
Pectin methylesterase & polygalacturonase

38. What is the Peroxide Value a measure of?
Speed of Light
Fat Oxidation
Oil in Water
Browning of freshly cut surfaces of fruits and vegetables.

39. What kinds of food emulsions are? (1) Butter (2) Mayonnaise(3) Milk
Tryptophan
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Lysine - Arginine - and Histidine
Four

40. What is the acid present in fish oil?
Degradation of protein and production of acid from sugar at the same time.
Arachidonic Acid
pH 3-5
Yellow

41. Is a disaccharide
pH below positive charge; pH at no charge; pH above negative charge
Speed of Light
Sucrose
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls

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

43. What does the acronym NPN stand for?
Non-protein nitrogen
Chitin
1 - 3 - 7-trimethylxanthine
Pectin Esterase - Polygalacturonase - Pectin Layase

44. What is the acid present in fish oil?
Arachidonic Acid
Fructose
Linoleic Acid
1 - 3 - 7-trimethylxanthine

45. The undesirable clarification of orange juice or tomato juice (precipitation of pulp) is caused by what enzymes?
Pectin methyl esterase or galacturonase
Arachidonic Acid
Negative log of the hydrogen concentration (mol/l).
Pectin methylesterase & polygalacturonase

46. What is catalase?
Thamautin
An enzyme that converts hydrogen peroxide to water plus oxygen.
Sodium bicarbonate generates CO2
Browning of freshly cut surfaces of fruits and vegetables.

47. To which of the following four basic tastes are humans most sensitive? A) Bitter B) Sweet C) Sour D) Salty
Pheophytin forms
Covalent (strongest) and Hydrophobic (Weakest)
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Bitter

48. What metabolic disorder prevents conversion of phenulalanine to tyrosine by normal metabolic pathways?
Phenylketonuria
Prolamines
Onions ( or leeks)
20 carbons and 4 double bonds

49. What does the acronym NPN stand for?
Initiation - Propagation - and Termination
Chlocophyllide does not have a phytoltail
Non-protein nitrogen
Troponins and Tropomyosin

50. Name the two components that comprise the relaxing factor in muscle fibers.
Milk
Primary butyric acid also caproic acid.
Troponins and Tropomyosin
Tryptophan