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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. To which of the following four basic tastes are humans most sensitive? A) Bitter B) Sweet C) Sour D) Salty
Glycosides of anthocyanidins
Acids - Alkalis - Metals - Organic Solvents - and Aqueous Solutions of Organic Solvents
Bitter
Gliadins and Glutenins

2. What is the chemical nomenclature for caffeine?
Sweet - Salty - Sour - and Bitter
It explodes
1 - 3 - 7-trimethylxanthine
Emulsification

3. Alar is the trade name for what chemical compound?
Orange Juice
Daminozide
Covalent (strongest) and Hydrophobic (Weakest)
Primary butyric acid also caproic acid.

4. What is Ohm's Law and What is Power Equation?
V=IR and P=VI or I x I x are
Bright green
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Emulsoids

5. A chlorophyll molecule reacting with hydrogen exhibits what shade of green?
Water
Carrageenan
Olive Green
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.

6. Name a commonly used household chemical leavening agent and the gas it generates.
HPLC has higher pressure than FPLC
The amount of unsaturated bonds in fat; grams Iodine reacting with 100 grams fat.
Arachidonic Acid
Sodium bicarbonate generates CO2

7. What are the four basic flavors perceived by the tongue?
Ascorbic Acid and Citric Acid
Non-protein nitrogen
Two aldehydes
Sweet - Salty - Sour - and Bitter

8. Name three nonpolar polar - and charged amino acids.
Nonpolar: (Valine - Alanine - Leucine - Isoleucine - Proline)Polar: (Glycine - Serine - Cystein - Threonine - Tyrosine)Charged: (Lysine - Arginine - Histidine - Aspartic Acid - Glutamic Acid)
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.
Osmosis
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants

9. Name the most common functional property of phospholipids in food systems.
Cis
Emulsification
A concentrate of microfibrillar proteins of fish muscle.
Whole Milk

10. Name 4 advantages of using enzymes in food processing.
Osmosis
The speed of a molecule is proportional to the surrounding voltage gradient.
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
Whole Milk

11. Which of these foods is not appropriate to this list? A) Salami B) Yogurt C) Orange Juice D) Beer
Orange Juice
Sucrose
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
They act as catalysts - speeding the polymerization of acrylamide.

12. Name one way foam stability can be assessed.
Water
Orange Juice
Gossypol (it is removed during the oil refining process)
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.

13. If the absorption of a sample is being determined spectrophotometrically at 420 nm what color is the sample?
A concentrate of microfibrillar proteins of fish muscle.
Cis
Yellow
Pheophytia does not have magnesium in porphyrin ring.

14. What is a polymorphism?
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
V=IR and P=VI or I x I x are
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.

15. S-(1-propenyl)-L-cysteine sulfoxide is the chemical precursor to the major flavor compounds In what foodstuff?
Onions ( or leeks)
Phenylketonuria
Fatty Acid and Alcohol
Sucrose

16. At what pH is benzoic acid most effective?
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Bitter
Phospholipids - water - sulfur compounds - soaps - partial glycerol esters - carbon dioxide - and mineral acids.
pH 3-5

17. 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?
Emulsification
pH below positive charge; pH at no charge; pH above negative charge
Racemic Mixture
.05 M HCL

18. What kinds of food emulsions are? (1) Butter (2) Mayonnaise(3) Milk
Two aldehydes
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Phenylketonuria
Initiation - Propagation - and Termination

19. Which amino acid has the greatest molecular weight: tryptophan or tyrosine?
Ascorbic Acid and Citric Acid
Tryptophan
Degradation of protein and production of acid from sugar at the same time.
No

20. What pigment was first designated as anthocyanins?
Blue pigment in flowers
2-mercaptoethanol (2-ME) - dithiothreitol (DDT)
Gossypol (it is removed during the oil refining process)
Fat Oxidation

21. What is the major color compound in tomatoes?
Lipase
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.
Lycopenes
Racemic Mixture

22. What are the three main steps in the autooxidation of lipids?
Initiation - Propagation - Termination
45% - 52% - 90%
Parabens
.05 M HCL

23. What chemical compound is responsible for the 'hot' principle of jalepeno peppers?
Ammonia - Water - Carbon Dioxide
ERH=100 x Aw
Monosodium Glutamate
Capsaicin

24. Name 3 factors influencing the rate of lipid oxidation in foods.
Pectin Esterase - Polygalacturonase - Pectin Layase
Fatty acid composition - free fatty acids versus the corresponding glycerols - oxygen concentration - temperature - surface area - moisture - pro-oxidants - antioxidants
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Thickener in foods

25. What is the structural difference between chlorophyll and chlocophyllide?
Olive Green
Pheophytin forms
Primary butyric acid also caproic acid.
Chlocophyllide does not have a phytoltail

26. What is the common name for 9 12 - cis-cis-octa dienoic acid?
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.
1 - 3 - 7-trimethylxanthine
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.
Linoleic Acid

27. What are the three stages of oxidative rancidity?
Plasmids
Initiation - Propagation - and Termination
Capsaicin
Erythorbic Acid

28. During freezing What are the two stages in the crystallization process?
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Thamautin
Gossypol (it is removed during the oil refining process)
Nucleation or crystal formation and crystal growth.

29. What is catalase?
Thickener in foods
Pectin Esterase - Polygalacturonase - Pectin Layase
Nucleation or crystal formation and crystal growth.
An enzyme that converts hydrogen peroxide to water plus oxygen.

30. Name two reasons why fats are hydrogenated.
Fructose
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
20 carbons and 4 double bonds
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.

31. 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.
Proportion of solids in the fat - number - size - and kinds of crystals - viscosity of the liquid - temperature treatment - and mechanical working.
Polyphenol Oxidase
For proteins: SDA-PAGE. For DNA & RNA: Agarose gel.

32. Name three non-nutritive sweeteners approved for use in USA?
Fatty Acid (Ester linked) to Fatty Alcohol
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.
Solid phases of the same chemical composition that differ by crystalline structure - but yield identical liquid phases upon melting.
Acsulfame-K - Saccharin - Cyclamate - Aspartame

33. What are proteins which are soluble in 50-80% ethanol known as?
Phenophylin
Thermus Aqauticus
pH 3-5
Prolamines

34. What are proteins which are soluble in 50-80% ethanol known as?
Aspartic Acid and Phenylalanine
100 Degrees Celsius (it is not a true solution-there is no boiling point of elevation)
1 - 3 - 7-trimethylxanthine
Prolamines

35. Name 2 heat stable enzymes in food that are important to the quality of aseptic products.
Thermus Aqauticus
Lipid oxidation
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.

36. What is the winterization process for an oil?
Decreased solubility - altered water-binding capacity - loss of biological activity - increased susceptibility to attack by proteases - increased intrinsic viscosity - inability to crystallize.
Sucrose
Gossypol (it is removed during the oil refining process)
Cooling the oil and filtering of the solids formed so that long chained saturated fats do not crystallize at low temperatures.

37. What compounds oxidize to form brown color in fruits and vegetables?
Daminozide
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Two aldehydes
Polyphenols

38. An emulsifier with a high hydrophilic-lipophilic balance (HLB) value would promote which type of emulsion: oil in water or water in oil?
Smoother - less acid and less bitter chocolate flavor - darker color - and improved solubility (elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids).
Oil in Water
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
Carrageenan

39. Name 5 chelating agents used in the food industry.
It allows the conversion of liquid oils into semisolid or plastic fats and it improves the oxidative stability of the fat.
Blue pigment in flowers
Lipase - lipoxygenase - catalase - chlorophylase - peroxidase - pectinase - protease - ascorbic acid oxidase - alkaline phosphotase.
EDTA - citric acid - malic acid - tartaric acid - oxalic acid - succinic acid - adenosine triphosphate - pyrophosphate - porphyrins - and proteins.

40. What is Ohm's Law and What is Power Equation?
Non-protein nitrogen
Molarity is moles of substance per liter solution. Molality is moles of substance per kg solvent. Normality is equivalents of substance per liter solution.
V=IR and P=VI or I x I x are
NaCl (it dissociated to a 2M solution)

41. In what food is butyric acid typically found?
Parabens
Troponins and Tropomyosin
Milk
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.

42. Name three factors useful in controlling enzyme activity.
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.
Sweet - Salty - Sour - and Bitter
Parabens
Temperature - Water Content and Activity - Extremes of pH - Chemicals - Alterations of Substrates - Alterations of Products - Preprocessing Controls

43. How does ERH relate to water activity?
Emulsoids
ERH=100 x Aw
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
An enzyme that converts hydrogen peroxide to water plus oxygen.

44. What does MSG stand for?
45% - 52% - 90%
Monosodium Glutamate
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Acsulfame-K - Saccharin - Cyclamate - Aspartame

45. What is the structural difference between chlorophyll and pheophytia?
Gossypol (it is removed during the oil refining process)
Degradation of protein and production of acid from sugar at the same time.
Pheophytia does not have magnesium in porphyrin ring.
Whole Milk

46. Will lipid oxidation be higher at a water activity of .05 or .5?
Gliadins and Glutenins
NaCl (it dissociated to a 2M solution)
Polyphenoloxidase
.05

47. What metabolic disorder prevents conversion of phenulalanine to tyrosine by normal metabolic pathways?
Phenylketonuria
Ammonia - Water - Carbon Dioxide
It explodes
14

48. What kinds of food emulsions are? (1) Butter (2) Mayonnaise(3) Milk
Amount of free fatty acids present; mg KOH needed to neutralize the free fatty acids in 1 g of fat.
Lipase
Butter= water in oil Mayonnaise= oil in water Milk= oil in water
Sweet - Salty - Sour - and Bitter

49. What two common compounds are used together as an antioxidative system?
Emulsoids
Initiation - Propagation - Termination
Sucrose
Ascorbic Acid and Citric Acid

50. What are the fructose contents in commercial HFCS products.
Orange Juice
Ascorbic Acid and Citric Acid
Sodium bicarbonate generates CO2
45% - 52% - 90%