Midterm 2 Flashcards
(150 cards)
1
Q
carbohydrates
A
most abundant organic molecules, initial source of all food, provide energy, carbon, fiber, sometimes taste, Cn(H2O)n
2
Q
GLUCOSE
A
C6H12O6 (hydrated carbon)
monosaccharide
3
Q
sugar nomenclature
A
suffix -ose, classified given the # carbons
4
Q
most foody sugars are made of…
A
hexoses
5
Q
hexoses…
A
D-aldohexoses, D-ketohexoses or hexuloses
6
Q
disaccharides
A
glucose, fructose
7
Q
glucose aka…
A
dextrose or grape sugar
8
Q
fructose aka…
A
levulose or fruit sugar
9
Q
sweetness
A
1 of 5 modalities
10
Q
various stages or degrees or refining form in order of increasing processing
A
molasses, raw sugar, brown sugar, white sugar
11
Q
MOLASSES
A
concentrate juices from sugar bearing plants (most often sugar cane), contains substances other than simple sugars. various grades and darkness
12
Q
open kettle and centrifugal
A
describe process of molasses
13
Q
edible and industrial
A
describe quality
14
Q
RAW SUGAR
A
should be 1st crystallization of sugar from boiling down (concentrating), sugar cane extract
15
Q
BROWN SUGAR
A
more “taste”/flavor than white sugar, hygroscopic (holds moisture and makes things stay moist)
16
Q
REFINED SUGAR
A
“sucrose”, only taste is sweetness, uniform quality, keeps indefinitely, source of nutritive energy, “empty calories”
17
Q
sugar’s influence on history
A
modern world vastly influenced by spice/sugar trades, history of slavery in New world intimately tied to sugar harvesting, production, fermentation
18
Q
“triangular trade”
A
never sail an empty ship, 1700s 1800s sugar, rum, slaves
19
Q
CORN SYRUP
A
cheaper sweetener obtained from hydrolysis of (corn) starches
20
Q
corn starches hydrolyzed by…
A
acids or ensymes
21
Q
“hydrolysis”
A
splitting a molecule apart and adding equivalent of water molecule to products
22
Q
partial hydrolysis produces…
A
glucose (dextrose), maltose, dextrins (higher MW polysaccharides)
23
Q
corn syrup properties
A
less sweet than sucrose, hygroscopic, mixture of polymers and fragments, inhibits crystallization of sugars
24
Q
high fructose corn syrups (HFCS)
A
ordinary corn syrup treated with enzymes, sweeter than regular corn syrup, can adjust Frc:Glc ratio
25
enzymes given suffix...
-ase
26
Honey
sucrose from plants converted from a disaccharide to two monosaccharides by enzyme "invertase", plus pollens, waxes, acids, etc.
27
what percent of sugar is fructose?
53%
28
reaction for honey
sucrose + H2O goes to glucose + fructose
29
concern about honey
is a vector for the bacterium "Clostridium botulinum"
30
honey and infants
in autopsies of infants who have died from SIDS, spores of C. botulinum have been found
31
MAPLE PRODUCTS
flavors and color produced during "boil down", 2/3 sugars, 1/3 h2o
32
SUGAR ALCOHOLS
hydrogenation of simple sugars (add H), many sugar alcohols exist naturally in nature especially plants
33
alcohol suffix
-ol
34
"Xylitol"
5C sugar alcohol, approx. sweetness of sucrose, anti- and non-carcinogenic properties, not regulated by insulin, price going down
35
Trident gum
Xylitol
36
correlation between artificial sugars and obesity
1. people on weight gain trajectory more likely to use lowcal sweeteners
2. sugar consumption causes satiety
3. over compensation
4. low blood sugar suppresses metabolism
5. AS very sweet, elevate sweetness tolerance
37
approved lowcal sweeteners
acesulfame potassium, aspartame, neotame, saccharin, sucralose, stevioside
38
"Acesulfame-K"
200x sweeter than sugar, calorie free, often combined with other sweeteners, approved 1988 as tabletop sweetener, approved for baked goods, frozen desserts, candies, and beverages,
39
Aspartame (NutraSweet)
200x sweeter than sucrose, aspartic acid, phenylalanine, problem with PKU disorder, esterfied with methanol (synthetic), "Equal", not heat stable
40
Neotame
6000x sweeter than sucrose, phenylalanine not released, 2002
41
Saccharin
300x sweetness sucrose, "Sweet 'N Low", can be carcinogin
42
Sucralose
600x sweeter than sugar, "Splenda", 1998 FDA declares tabletop sugar, now general purpose sweetener, cannot be digensted
43
LowCal sweeteners FDA approval expected 2006
Alitame (2000x sweeter), Cyclamates (30x sweeter)
44
other naturally-occuring sweeteners being studied
glycyrrhizin (licorice extract), stevivoside or stevia (plant extract
45
MALTOSE
"malt sugar", prepared by yeasts or enzymes acting upon starches, DISACCHARIDE, not common in nature
46
LACTOSE
disaccharide from mammalian milks, glucose+galactose; commercially prepared from whey; 1/6 sweetness of sucrose, low soubility
47
latin "lac" means...
milk
48
greek "gala" means...
milk, milky way
49
human milk consumption
only species to consume milk of other species and after weaning
50
who drinks most milk in world?
northern europeans, others often are lactose intolerant
51
lactose intolerance
decrease and lose production of lactase and cannot digest lactose
52
use of lactase enzymes...
1. directly in processing
2. naturally with fermented dairy products
3. dietary supplements "lact-aid"
53
other things in dairy might cause digestion discomfort
1. cheese concentrated milk proteins and fat
2. lactose concentration begins at about that of milk
3. ripening reduces lactose concentration in cheese and yogurt
54
country with largest cheese consumption
greece then france then italy
55
STARCHES
polysaccharide, amylose (linear)+amylopectin (branched)
56
examples of starch
amylose, cellulose
57
most abundant polysaccharide
celluose
58
amylose starch
straight chain that forms coils
59
most common starch
amylose
60
what is located in the "starchy endosperm" of a wheat kernel
starch granules and proteins associated with them, 83% of kernel
61
what makes starch granules swell
heat, they fill with water; evenually a "sol" solution formed; when cooled a gel forms from starch granules trapping water
62
what is a "Gel"
solvent entrapped in network of polymer
63
examples of "gel"
1. "starch" chocolate pudding 95% water
| 2. "protein" jello 97% water
64
difference between "regular" and "instant" pudding
1. regular must be heated to gelatinize starch
| 2. instant just needs milk and mixed; has pre-gelatinized starch which prevents rapid retrogradation
65
"retrogradation"
realignment of starch polymers that causes expulsion of water
66
what does retrogradation cause in bread
staleness
67
amylopectin
starch that contains alpha branches NOT PECTIN
68
more amylopectin means...
less retrogradation
69
starches with high amylopectin %s called...
"waxy" starches; ex. cornstarch
70
what do manufacturers do to prevent retrogradation
chemically modify starches (must be labeled as "modified starch"
71
AMYLASE
enzyme used to breakdown starch
72
two major types of amylase
1. alpha (random attack)
| 2. beta (cleaves off maltose)
73
amylase in brewing
malting processes in brewing where starch in barley is broken down to maltose and glucose in order for yeast to ferment
starch into alcohol
74
American Association of Cereal Chemists' definition of DIETARY FIBER
edible parts of plants or analogous CHO that are resistant to digestion and absorption in human small intestine with complete or partial fermentation in the large intestine
75
dietary fiber includes...
polysaccharides, oligosaccharides, lignin, and associated plant substances
76
what does fiber do for GI tract
provides bulk to help move material
77
feces are...
75% water, 25% solids
78
the solids of feces are...
1. insoluble fiber (undigestible); acts as bowel irritant; draws water out of lumen; cleans out lower GI
2. solube fiber (partially digestible); lowers cholesterol concentration (more cholesterol converted to bile salts and pulled from bloodstream
3. 20% dead bacteria
4. 10-20% fat
79
dietary fiber components...
1. cellulose
2. hemi-celluloses
3. gums and mucilages
4. pectins
80
PECTIN
linear polymer of mostly galacturonic acid; METHYL ESTER
81
what does nature use to cement plant cell walls together
pectin
82
what happens when plant cells are heated?
release broken "chunks" of cell wall pectin to form smaller molecules we call "ordinary pectin"
83
can boil some fruits and release enough pectin to make a gel BUT...
need to have acid and sugar present to form gel
84
gel+sugar
jelly (or jam)
85
things that are not pectin at all but are GELS...
thickeners and gums
86
thickeners and gums...
polysaccharide derivatives; "natural" products
87
famous thickeners and gums
locust bean gum; carrageenan; alginate; xanthan gum; guar gum
88
BRAN
hard outer layer of grain
- consists of combined aleurone and pericarp
- integral part of whole grains
89
pericarp contains...
fiber
90
vlad the impalers castle
?
91
where is bran in a wheat grain
mix of aleurone (outer layer of endosperm) and pericarp
92
roles of fats
E source; texture; adipose; essential fatty acids; fat soluble vitamins (A, D, E, K); flavor and flavorings; heat transfer; fatty acid isomers (trans fats)
93
caloric values of CHO, proteins, fats respectively
4 kcals/gram; 4 kcals/gram; 9 kcals/gram
94
2015 dietary guidelines for fat
less than 35% total calories from fats/oils; controversial and always in revision
95
what is the polymer of the subunit "fatty acids"
triglycerides
96
TRIGLYCERIDE
3 fatty acids attached to glycerol
97
saponification
treatment of fats with a strong base to give salts of fatty acids; used to remove fatty acids
98
triglyceride hydrolysis
needed for digestion; use lipases; ONLY FREE FATTY ACIDS ARE ABSORBED
99
diff between fats and oils
fats are semi-solids @ room temp; oils liquid @ room temp
100
games of the fat industry
1. food industry lables fat% by weight and tell how fat isnt there (95% fat free)
2. nutritionists recommend less than 30% fat by calories; now 40%
- FAT BY CAL DIFF THAN FAT BY WEIGHT
101
by diluting food with water, the % fat (by weight)......
goes down, but does not change % calories from fat
102
low fat franks fat %s
3% fat by weight
| 20% of calories from fat
103
LOW-FAT TYPES
simplesse, olestra
104
Simplesse
made from dairy and egg proteins; formulated as powder; may have problems with heating; 1 cal vs 9 cal
105
Olestra (controversial)
chemically bonds fatty acids onto sugar molecules; so large they are indigestible; causes abdominal cramping and loose stools; inhibits absorption of some vitamins and other nutrients
106
texture of fats
cocoa butter; polymorphism
107
polymorphism of fats
cocoa butter
108
cocoa butter
6 crystal forms; have different shapes and ways of packing; different melting points
109
nicest form of cocoa butter
type V
110
most stable form of cocoa butter
type VI (highest mp)
111
how do you make all crystals type V
controlled heating/cooling
112
"chocolate bloom"
caused by different crystal type from V to VI because of temp changes
113
adipose tissue
marbling of meat "kobe beef"
114
essential fatty acids are..
essential to proper metabolism; cannot be synthesized by body; thought related to production of powerful hormones and biochemicals (prostaglandins, leucotrienes, thromboxanes)
115
essential fatty acids
linoleic, linolenic, arachidonic
116
prostaglandins
originally isolated from seminal fluid
117
fat soluble vitamins
A, D, E, K
118
effects of fats on flavor
1. storage of flavor compounds
2. specific for product
3. without fat, flavor is problem
119
"aint nothin good without the grease"
fat flavoring, tina turner
120
heat transfer of fats
large molecules do not evaporate, can be heated to high temp; heat transfer with hot fat is called frying
121
double bond in fatty acid
causes "kink"; unsaturated
122
saturated fatty acide
stearic acid
123
OMEGA NUMBERS
the last carbon is like the last letter in greek alphabet (omega); they number in from the omega until they come to the first double bond
124
fatty acid types...
polyunsaturated; monosaturated; saturated
125
fat isomers
cis and trans double bonds
126
proportions of fatty acid types...
?
127
cis fat
double bonds found in FA's in nature
128
trans fat
double bonds formed as byproducts of synthetic chemistry process called "hydrogenation";
129
catalytic hydrogenation fo fats
converting veggie oil to margarine; saturating SOME of double bonds (partial hydrogenation); converts cis to trans
130
proteins as food
source of amino acids; source of calories (energy)
131
proteins in the body
structural; contractile; enzymes; receptors; transporters; antibodies; e- carriers; hormones; enzyme inhibitors; O2 transport/binding
132
aa's composed of...
1. acid part
2. amino part
3. R group
133
main types of protein structure
1. fibrous= insoluble in water
2. globular= soluble in water
3. membrane= insoluble in water
134
what breaks apart proteins
hydrolysis; ONLY ABSORB AND DIGEST INDIVIDUAL AMINO ACIDS
135
example of secondary protein structure
lays, gives strength
136
denaturing of a protein
how egg albumin changes from soluble liquid to insoluble gel or from soluble liquid to foam
137
tertiary structure of proteins determines...
solubility (fibrous vs globular which is tertiary)
138
how to turn gristle in steak to good meat
water+heat
139
quaternary proteins
collagen
140
collagen
triple helices (tropocollagen) of proline rich peptides, covalently cross linked
141
formation of gelatin
collagen unwound by heating in salt water (slow-roasting)
142
other uses for gelatin
dietary supplement, nails
143
seed proteins
starchy endosperm is 85% of kernel, 10-15% of that is protein
144
gluten proteins
prolamins, glutelins
145
more protein means...
more glutenins, stronger dough
146
all enzymes are...
proteins, but not all proteins are enzymes
147
effect of phylogenetic distance from humans
best protein is from other humans but next best is from other animals
148
essential amino acids
body cannot metabolize or make on own, must be consumed in diet
149
when protein low in essential amino acid, considered...
LIMITING FACOR
150
supplementary aa's
adding supplemental aa to make up for lacking
