Chapter 8: Sugar: The Simplest of Carbohydrates Flashcards
1
Q
What are carbohydrates made up of?
A
C, O, H
2
Q
Name some bodily functions of carbs.
A
- Major source of E
- Vital part of cell structure
- Base of DNA (and RNA) molecules
3
Q
What do carbohydrates include?
A
Sugars, starches and fibre
4
Q
What is the simplest form of carb?
A
Sugars
5
Q
What is the chemical name for sugars?
A
Saccharides
6
Q
What are saccharides composed of?
A
One or more hydroxyl groups
7
Q
What do monosaccharides contain?
A
C, H, O atoms in a central ring structure
8
Q
Name the 3 monosaccharides and examples.
A
Fructose: fruit, honey
Galactose: milk
Glucose: basic source of E
9
Q
What are disaccharides
A
2 monosaccharides
10
Q
Name the 3 disaccharides.
A
Sucrose
Lactose
Maltose
11
Q
What is maltose made up of?
A
Glucose + Glucose (malted grains)
12
Q
What is sucrose made up of?
A
Glucose + Fructose (table sugar)
13
Q
What is lactose made up of?
A
Glucose + Galactose (milk)
14
Q
How do we digest disaccharides?
A
Hydrolysis (add H2O)
15
Q
Do all disaccharides use the same enzyme to digest?
A
No, all require a different one
16
Q
What is invert sugar?
A
The fructose and glucose mixture that results from the hydrolysis of sucrose by sucrase is called invertase
-> sugar comes from broken down sucrose
17
Q
What do alcohols all contain?
A
At least one OH- group
18
Q
Name 4 types of alcohols and give examples.
A
- Ethanol (alcoholic beverage)
- Methanol (burning wood without O)
- Isopropanol (rubbing alcohol)
- “Sweet alcohols”: glycerols
19
Q
Give examples of “sweet” alcohols.
A
Glycerol, mannitol, sorbitol, xylitol
20
Q
Which “sweet” alcohol is a cryoprotectant?
A
Glycerol
21
Q
How many kcals/g do carbs have?
A
4kcal/g
22
Q
How are sources of sugar listed on a food label?
A
Listed seperately
23
Q
Why are artificial sweeteners used? How are they extracted?
A
- Used to optimize sweetness + cheap
- Extracted from plants
24
Q
Who developed sugar cane extraction processes?
A
Chinese
25
How is molasses made?
Crude boiled liquid pressed from sugar cane
26
What is brown sugar?
Unrefined or partially refined cane sugar
27
How is confectioner's sugar made?
Granulated sugar that is ground into a fine powder
28
What do sugar beets perform the same function as?
As sucrose from cane sugar but CHEAPER
29
How is maple syrup made?
Sap of sugar maple trees, slowly simmered to make syrup
30
How is maple syrup adultered?
Corn syrup
31
How is corn syrup processed?
Hydrolyzing cornstarch into glucose
32
What is corn syrup composed of?
Varying amounts of dextrose, maltose, dextrins or polysaccharides
33
How is high fructose corn syrup made?
Enzymatically converting some of the dextrose in corn syrup to fructose
34
How is sorghum made?
Sap extracted from sorghum canes and boiled to evaporate excess H2O
35
What does sorghum ressemble?
molasses
36
How is honey made?
bees extract invert sugar from the pollen of flowers and store in hives
37
What does the taste of honey depend on?
type of flower
38
What is isomalt made of?
mannitol, sorbitol, beet sugar
39
How is isomalt used?
blown, spun, shaped sugar sculptures - does not form crystals
it liquefies at 154oC
40
Name the 6 functions of sugar in food preparation.
1) Sweeten foods
2) Act as preservatives
3) Act as tenderizers
4) Act as crystallizing agents
5) Act as caramelizing agents
6) Act as fermenting agents
41
What causes the ability to sweeten?
sugars have up to 10 units of monosaccharides
42
What influences sweetness?
Sweeter the sugar, simpler the structure
43
How does the body recognize sugar?
Sugar binds to taste buds via H-bonds
44
How do sugars act as preservatives?
prevent food spoilage by drawing H2O away from bacteria (lowers Wa)
45
Which sugar is most affective in maintaining freshness of baked goods?
Invert sugar
46
How does sugar affect crumbs?
The + sugar a baked product contains, the more tender the crumb
47
How does sugar change viscosity?
Sugar interferes with flour's ability to form an elastic structure
-> pours easier with sugar
48
Why does sugar dissolve in H2O?
large number of hydroxyl groups, forms hydrogen bonds, water molecules surround sugar, suspending sugar in a water solution
49
What happens when sugar solutions are heated?
H2O evaporates, increasing sugar concentration
50
What does supersaturated mean?
If a sugar solution has been heated to concentrate it and is then cooled: any solution that has been heated to dissolve more solute than the water would normally hold is called supersaturated
51
How is candy made?
When sugar crystals separate from a supersaturated sugar solution during cooling
52
What differentiates high and low quality chocolate?
High quality = fine sugar crystals
53
Name the 5 factors affecting crystal formation.
1) Cooling time
2) Ripening
3) Type of sugar
4) Interfering agent
5) Agitation
54
What is cooling time?
cooler syrup = crystalizes rapidly = creamy smooth
55
What is ripening?
allowing candy to rest promotes a smooth creamy texture (ex: fondant)
56
What is the type of sugar?
sucrose increases sugar size (large crystals), invert sugar slows crystal formation
57
What are interfering agents?
corn syrups, butter, egg white, cream of tartar, cream, vinegar = prevent/slow crystal growth
- corn syrup = much glucose -> finer, smaller crystals
- Fat and protein in eggs: suspend and separate sugar crystals
- acid: hydrolyze the sucrose in a sugar solution
58
What is agitation?
stirring -> large crystals in hot syrup, but prevents them in cooled syrups
59
Name 2 candy making tips.
- Monitor temp with candy thermometer
Concentration of the sugar solution
Size of the sugar crystals
- Follow preparation directions carefully
1) Concentration of the sugar solution
2) Size of the sugar crystals
60
How do sugars act as caramelizing agents?
Caramelization occurs when sugar is heated for a prolonged period and darkens to brown liquid
61
How do sugars function as fermenting agents?
fuel for microorganisms growth needed for fermented products (yeast breads, beer, wine)
Glucose + yeast -> ethanol (alcohol byproduct)
62
What does fructose and lactose become?
glucose in liver
63
Where does excess glucose go?
Stored as glycogen in muscles and liver
64
Name 3 bodily functions of sugar
Needs sugar for digestion of fats and proteins
Needed for brain function
Sugars release serotonin (calming effect, addictive)
65
What is dietary guideline for added sugar?
6.5% ADDED MAX of total kcals
66
Name 3 sugar health concerns.
- Dental caries
- Diabetes mellitus
- Weight gain
67
How do cavities form?
bacteria feeds on sugar -> produces plaque
68
How does diabetes form?
body's inability to move glucose from bloodstream to cells because of insulin levels
69
How does weight gain form?
consuming excess kcals
70
How much is the earth's biomass made of carbohydrate? Its dry mass?
```
Biomass: 50%
Dry mass (land plants and seaweed): 75%
```
71
Why is baby corn sweeter than its full-size counterpart?
Since initially all carbs = glucose. As the plant matures, it changes into more complex starches
72
Define an organic compound.
Containing MORE than 1 carbon
73
What is a hydroxyl group?
OH bound together
74
Name differences between a-D-glucose and b-D-glucose.
a-D-glucose: OH down, basic source of energy for humans
| b-D-glucose: OH up, main component of dietary fibre, undigestible
75
Define riboses.
Sugars that contain only five carbon atoms.
76
Why are sweetened drinks not as thirst quenching as plain water?
Part of the H2O is used to digest the sugar and is not available for other functions
77
Name the 3 conditions that can trigger hydrolysis.
1) Presence of an enzyme
2) Addition of an acid
3) Addition of heat
78
How is lactose-free milk produced? Why is it sweeter?
Adding an enzyme to hydrolyze the sugar, sweeter because the lactose is broken down into glucose and galactose
79
What produces lactase? Why is milk difficult to digest after taking antibiotics? Why does eating yogurt help?
- Bacteria in the small intestines
- Antibiotics will kill these bacteria
- Yogurt may contain an active culture of Lactobacillus acidophilus
80
Name a source of glycerol.
Animal fats
81
What is the composition of molasses (which varies by degree of refinement)?
- 35-50% sucrose
- 15-20% invert sugar
- 20-25% water
- 2 to 5% mineral
82
What is the composition of brown sugar?
85 to 92% sucrose
83
What gives brown sugar its moist moist texture and distinctive colour?
Molasses
84
What happens when brown sugar is left in the open?
Loss of moisture, becomes hard and crumbly, moist texture can be regained by adding apple slices or a slice of fresh bread to the container (sugar will absorb moisture from substances)
85
Define granulated sugar.
When further processing removes all minerals, flavourings, and colouring agents from brown sugar, leaving only the crystalline structure.
86
What does most confectioner's sugar has added to help prevent caking during storage?
Cornstarch
87
What does the number of Xs on the label of confectioner's sugar refer to?
How finely the sugar has been ground - the larger the nb, the finer the powder (4X, 6X, 10X)
88
Give examples for the different types of confectioner's sugar.
4X: cough drops, chewing gum, marshmallows, chocolate
6X: cream fillings, uncooked fondants, icings, sprinkled on buns, pies and pastries
10X: finest icings and fondant fillings
89
How many gallons of tree sap do you need to make maple syrup?
40 gallons of tree sap, slowly simmered down, to make one gallon of maple syrup
90
Define dextrose.
The name for glucose used by the confectionary trade.
91
How can we make corn sweeteners? How can its sweetness be altered?
Technology has made it possible to use enzymes to convert starch from abundant corn supplies into sweet syrups. Its sweetness can be altered by varying the hydrolysis process
92
Which sweetener was the first used in food preparation?
Honey
93
What is the composition of honey?
75% invert sugar, 15-20% water
94
What is the composition of HFCS?
55% fructose and 45% glucose
95
Which sugar helps products such as cakes stay moist the best?
Invert sugar maintain freshness considerably longer than sucrose
96
What happens when bread does not contain any sugar?
Paler colour and chewier texture (sugar as tenderizer)
97
What does invert sugar occur naturally in?
Honey and molasses; is also produced commercially
98
How does invert sugar help in candy making?
Helps prevent the crystallization and resulting graininess of candy caused by cane and beet sugar because invert sugar is made of two monosaccharides (and not two disaccharides) - so finer texture
99
What happens when you don't let candy cool and you stir too early?
Cause crystals to come out of the slightly supersaturated mixture - causes crystallization to occur slowly rather than rapidly --> larger crystals / grainy texture
ex: taffies and fondants are cooled on a marble slate
100
Why do some fondants have invertase added after cooking?
Furthers hydrolysis of disaccharides into invert sugar -> candy has a smooth, fine, even texture that is semisoft to liquid
101
Why do certain cookbooks never recommend to make fudge on a rainy day?
Since a very humid day will change the sugar-water balance in candy as it cools, may reduce sugar concentration to keep fudge from setting
102
Name some examples of caramelization.
- Brown crust on baked goods and toast
- Beige colour of sweetened condensed milk
- Colour of caramel candy
- Flan (caramel custard)
103
What might explain caramelization?
Dehydration is at least partially responsible for the browning and resulting flavour changes
104
What do the Dietary Guidelines recommend limiting added sugars to? What is the average intake in the US?
Recommend: 6.5%
Average: 16%
105
How is invert sugar made commercially?
Addition of acids to sucrose, followed by a neutralization process
106
What is the equation for photosynthesis?
6 CO2 + 6 H2O + sunlight -> C6H12O6 + 6 O2
