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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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1. What kinds of food emulsions are? (1) Butter (2) Mayonnaise(3) Milk
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Number of fatty acids present; mg KOH needed to saponify 1 g fat.
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
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. What name is given to the small circular DNA molecules that carry genetic information independently of the main bacterial chromosome?
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
It explodes
Plasmids
Osmosis

3. Name 3 physical agents capable of denaturing proteins.
Capsaicin
Racemic Mixture
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces
Fat Oxidation

4. What is the name given to a mixture of equal parts of Darel Lisomers?
Gliadins and Glutenins
Racemic Mixture
Polyphenol Oxidase
Linoleic Acid

5. What does Acid Degree Value measure and how is it measured?
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
RNA transcribed to DNA
Blue pigment in flowers
Glycosides of anthocyanidins

6. What are the limiting amino acids in corn - potato - and green peas?
Corn- Lysine - Potato-Methionine - Green Peas-Methionine
pH below positive charge; pH at no charge; pH above negative charge
.05
Initiation - Propagation - Termination

7. What are the three main steps in the autooxidation of lipids?
No
Osmosis
Initiation - Propagation - Termination
Fatty Acid (Ester linked) to Fatty Alcohol

8. What ketohexose is most significant to food chemists?
Fructose
ERH=100 x Aw
Whole Milk
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).

9. What does MSG stand for?
Monosodium Glutamate
They act as catalysts - speeding the polymerization of acrylamide.
Daminozide
Osmosis

10. Name three factors useful in controlling enzyme activity.
Emulsification
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Tryptophan
Capsaicin

11. Peptide bond formation results in the formation of what secondary compound?
Water
Covalent (strongest) and Hydrophobic (Weakest)
No
Emulsoids

12. Name the three positively charged amino acids.
Lysine - Arginine - and Histidine
Whole Milk
Thamautin
Heat - Cold Mechanical Treatments - Hyrdostatic Pressure - Irradiation - and Interfaces

13. What does Reichert-Meissert Number measure?
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
Lycopenes
Primary butyric acid also caproic acid.
Bitter

14. What is surimi?
A concentrate of microfibrillar proteins of fish muscle.
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Aspartic Acid and Phenylalanine
Sweet - Salty - Sour - and Bitter

15. Name two non-enzymatic browning reactions.
Carmelization and Maillard
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Daminozide
Thamautin

16. Name two main gluten proteins.
Lamellar; Hexagonal I - II; Cubic
Daminozide
Four
Gliadins and Glutenins

17. Name 5 chelating agents used in the food industry.
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Parabens
Polyphenol Oxidase
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.

18. Name 5 proteins with good foaming properties.
Fatty Acid (Ester linked) to Fatty Alcohol
Monosodium Glutamate
Troponins and Tropomyosin
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.

19. Peptide bond formation results in the formation of what secondary compound?
.05
Water
Fat Oxidation
Thickener in foods

20. What are proteins which are soluble in 50-80% ethanol known as?
Prolamines
Emulsoids
Orange Juice
Chlocophyllide does not have a phytoltail

21. What is the name of the structural carbohydrate found in lobsters crab - shellfish - and insects?
Chitin
Gossypol (it is removed during the oil refining process)
Lipase
Thickener in foods

22. What does the iodine value measure and how is it measured?
Water
Acetoin
Cis
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.

23. What enzyme causes hyrolytic rancidity in milk?
Non-protein nitrogen
Lipase
Gossypol (it is removed during the oil refining process)
20 carbons and 4 double bonds

24. Food additive that could be used to prevent cocoa particles from settling in chocolate milk
Yellow
Initiation - Propagation - Termination
Carrageenan
Degradation of protein and production of acid from sugar at the same time.

25. If the absorption of a sample is being determined spectrophotometrically at 420 nm what color is the sample?
Pheophytia does not have magnesium in porphyrin ring.
Emulsoids
20 carbons and 4 double bonds
Yellow

26. What is the winterization process for an oil?
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)
Orange Juice

27. Name three nonpolar polar - and charged amino acids.
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
NaCl (it dissociated to a 2M solution)

28. What metabolic disorder prevents conversion of phenulalanine to tyrosine by normal metabolic pathways?
Phenylketonuria
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
Cis
Nucleation or crystal formation and crystal growth.

29. In what food is butyric acid typically found?
Polyphenol Oxidase
Monosodium Glutamate
Milk
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls

30. What is acid proteolysis?
Speed of Light
Degradation of protein and production of acid from sugar at the same time.
The speed of a molecule is proportional to the surrounding voltage gradient.
4:0 (Butyric) - 10:0 (Capric) - 12:0 (Lauric) - 14:0 (Myristic) - 16:0 (Palmitic) - 18:0 (Stearic)

31. Name 3 chemical agents capable of denaturing proteins.
Pectin Esterase
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Emulsoids

32. Name the three positively charged amino acids.
Speed of Light
Gossypol (it is removed during the oil refining process)
RNA transcribed to DNA
Lysine - Arginine - and Histidine

33. How many carbon atoms are there in the fatty acid myristic acid?
Bright green
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
14
Pectin methylesterase & polygalacturonase

34. How many carbon atoms are there in the fatty acid myristic acid?
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.
14
Emulsoids
pH 3-5

35. Name the strongest biochemical bond and the weakest biochemical bond.
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
Covalent (strongest) and Hydrophobic (Weakest)
Racemic Mixture
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.

36. What is catalase?
Sodium bicarbonate generates CO2
An enzyme that converts hydrogen peroxide to water plus oxygen.
Water
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)

37. What are soluble polymers of anhydro-galacturonic acid and its esters called?
Bitter
Browning of freshly cut surfaces of fruits and vegetables.
Pectins
ERH=100 x Aw

38. Name 2 heat stable enzymes in food that are important to the quality of aseptic products.
45% - 52% - 90%
Pheophytia does not have magnesium in porphyrin ring.
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Fatty Acid and Alcohol

39. What metabolic disorder prevents conversion of phenulalanine to tyrosine by normal metabolic pathways?
ERH=100 x Aw
Yellow
Phenylketonuria
Glycosides of anthocyanidins

40. Does kosmotrophil ion discourage water structure?
Negative log of the hydrogen concentration (mol/l).
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
No
Anthocyanins

41. What two common compounds are used together as an antioxidative system?
Fructose
Ascorbic Acid and Citric Acid
Whole Milk
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).

42. What happens to chlorophyll on heating?
Pheophytin forms
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
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.
Arachidonic Acid

43. At low water activity What is the main deteriorative concern?
Ammonia - Water - Carbon Dioxide
Olive Green
Lipid oxidation
Speed of Light

44. Name one way foam stability can be assessed.
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
Pheophytia does not have magnesium in porphyrin ring.
Glycosides of anthocyanidins
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.

45. What chemical compound is responsible for the 'hot' principle of jalepeno peppers?
Chitin
Sodium bicarbonate generates CO2
.05 M HCL
Capsaicin

46. What pigment was first designated as anthocyanins?
Polyphenols
The speed of a molecule is proportional to the surrounding voltage gradient.
Polyphenol Oxidase
Blue pigment in flowers

47. What does the acronym NPN stand for?
Non-protein nitrogen
Racemic Mixture
Fatty Acid (Ester linked) to Fatty Alcohol
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)

48. Name 5 proteins with good foaming properties.
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.
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.
Acsulfame-K - Saccharin - Cyclamate - Aspartame
Fatty Acid (Ester linked) to Fatty Alcohol

49. What are 3 mesomorphic structures associated with lipids in the liquid state?
Lamellar; Hexagonal I - II; Cubic
Speed of Light
Initiation - Propagation - Termination
.05

50. What is the geometric configuration of double bonds in most natural fatty acids?
Carmelization and Maillard
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls
Cis
Chitin