Transcript Carbohydrates

Carbohydrates
Carbs in Your Diet

60% food calories should be
carbohydrates
Lowest 50%
Highest 75%

Refined sugars 0%- 10%


Carbohydrate in the body
Used and stored in the body in a variety of
ways:
- helps the body use proteins and fat
- used to provide energy for the body
- [fiber] aids digestion
- required to run the brain
Metabolism:
How fast is your engine
running?
Carbs:

Are organic compounds
Are made of
Carbon + hydrogen + oxygen

Are made by
plants


Q: How are Carbs made?
A: Photosynthesis
Chlorophyll & sunlight
carbon dioxide + water
(CO2)
(H2O)
glucose + oxygen
(C6H12O6)
This is a carb!
(O2)
CO2 – comes from the air
H2O – comes from the ground
Chlorophyll- green pigment in plants
C6H12O6 – Glucose, the basic sugar molecule
from which all other CHO’s are built
O2 – oxygen, the gas released as a waste
product

A plant can
convert glucose
into other
sugars,
starches and
fibers.
Types of Sugars (aka saccharides):
Monosaccharide
Disaccharides

All carbohydrates are broken down
into monosaccharides when digested
Monosaccharides:

Aka “single sugars”
Glucose - building blocks for all other sugars
Fructose - found in fruits and sap, very sweet
Galactose – found in milk
Glucose – simple sugar
C6H12O6






6 sided ring
6 carbon
12 hydrogen
6 oxygen
Hydroxyl group
combination of hydrogen
and oxygen containing
one atom of each -OH
- is the chemical bond
that attaches the group
to another
Fructose – fruit sugar
C6H12O6
Galactose – milk sugar
C6H12O6
Isomers
Chemicals that have the
same formula but different
structures
 Ex: glucose, fructose &
galactose

Disaccharides

Aka “double sugars”
made from 2 monosaccharides

Sucrose – table sugar, very sweet

Lactose – found in milk

maltose- found in cereals

Sucrose- “table sugar”
(glucose + fructose)
Lactose – milk sugar
Maltose – grain sugar
(glucose + glucose)
Dehydration Synthesis
When 2 monosaccharides are
combined,
H from one and OH from the other
leave so they can fit
together…..synthesis
1 molecule of water is
removed…….dehydration
Hydrolysis
When 2 or more
monosaccharides are split
up,
H2O must be added……H
adds to one, OH adds to the
other to give the original
monosaccharides
When chemical bonds break,
energy is released!
Properties of sugar
Sweetness
 Soluability
 Caramelization
 Crystallization

Sweetness



some sweeter than others
Fructose> sucrose>
glucose> galactose>
maltose> lactose
Sweetness depends on
concentration, consistency,
temperature and ph balance
Sugar in processed food





½ c. canned corn
12 oz cola
1 tbsp ketchup
1 small yogurt
2 oz chocolate
3 tsp
8 tsp
1 tsp
7 tsp
8 tsp
Solubility


ability to dissolve in water mirrors
their sweetness.
Fructose> sucrose> glucose>
galactose> maltose> lactose
Carmelization


the browning reaction (called Maillard’s
Reaction) that can occur with any kind of
sugar when heated.
Sugars differ at the temperature they
caramelize.
Name
Temp
Description
Thread
223235* F
The syrup drips from a spoon, forms thin threads in
water
Soft
ball
235245* F
Usage
Glacé
The syrup easily forms a ball while in the cold water, but
flattens once removed
and candied
fruits
Fudge
and fondant
Firm
ball
245250* F
The syrup is formed into a stable ball, but loses
its round shape once pressed
Hard
ball
250266* F
The syrup holds its ball shape, but remains
sticky
Soft
crack
270290* F
The syrup will form firm but pliable threads
Caramel
candies
Divinity
and marshmallows
Nougat
and taffy.
Hard
crack
300310* F
The syrup will crack if you try to mold it
Brittles and
lollipops
Caramel
320350* F
The sugar syrup will turn golden at this stage
Pralines
Crystallization


Affected by- water temperature,
Supersaturated- solution that holds
more dissolved solute than it would at
room temperature.
“Rock” Candy on a stick

made using
crystallization
of a
supersaturated
sucrose
solution
Nutrition Link: Page 225


Carbohydrates in a Healthful Diet
Read, the answer #1 & 2
Using Your Knowledge: page 236
Answer #1 – 6, 9.
Sugar and health
Natural sugars
in food are
better for you
than eating
sugar.
Artificial
Sweetners


Added to foods to sweeten, chemically
differ from natural sweetners
No calories
Sucralose
“splenda”-600x sweeter than sucrose
Sucrose
Acesulfame K
Sucrose
Saccharine
300x sweeter than sucrose
Sucrose
Neotame
8,000 and 13,000 times
sweeter than sucrose
Sucrose
Mannitol
Sucrose
Sorbitol
0.5x as
sweet as
sugar
Xylitol
Digestion of
sugar



Sugar broken down
into Monosaccharides
with enzymes
Glucose + insulin [from
pancreas]
Absorbed into the
blood stream
Glucose in the blood too high?
  insulin triggered to remove
glucose

 liver + muscle cells store
excess as glycogen (animal
starch)
Glucose level in blood too low?
  glycogen (animal starch)
retrieved from liver and
muscles
  returned to blood as
glucose
HEALTH CONNECTION:
Diabetes
body can’t regulate glucose levels.
 Pancreas cannot make enough
insulin to carry all of the glucose
produced from carbs into the body’s
cells
 Glucose continues to circulate in the
body until it is excreted in the urine

Hyperglycemia





Very high blood glucose level.
Diabetic coma
Require more insulin
Hard on body  glucose excreted
through kidneys  leads to kidney
damage over long term.
Strains heart
Hyperglycemia (High Blood Sugar)
CAUSES:
ONSET:
BLOOD
SUGAR:
WHAT CAN
YOU DO?
Too much food, too little insulin,
illness or stress.
Gradual, may progress to diabetic
coma.
Above 200 mg/dL.
Normal range: 70-115 mg/dL
Test blood sugar
If over 250mg/dL for several
tests, CALL YOUR DOCTOR!
Hypoglycemia
Low level of glucose in
blood
 Dizzy, weak, nausea

Hypoglycemia (Low Blood Sugar)
CAUSES:
Too little food, too much insulin or diabetes
medicine, or extra exercise.
ONSET:
Sudden, may progress to insulin shock.
BLOOD
Below 70 mg/dL. Normal range: 70-115
SUGAR:
mg/dL
Drink a cup of orange juice or milk or eat
several hard candies
Test Blood sugar
Within 30 minutes after symptoms go away,
eat a snack e.g. sandwich, and a glass of milk
WHAT CAN
YOU DO?
Contact doctor if symptoms don’t stop
Type 1- diabetes



Juvenile
Pancreas secretes little
to no insulin
Requires insulin intake
Type 2 - diabetes




Late onset – usually after 40 yrs
The pancreas fails to produce enough
insulin.
Control by diet and exercise
Control by pills- they force the pancreas
to produce more insulin
These factors combine to cause
type 2 diabetes
Polysaccharides



Aka “complex carbohydrates”
2 Types:
1. Starches – plant’s stored food
-taste rather bland
- stored in granular form
2. Fiber- gives plants their structure
cellulose, pectins
Starch consists of two types
of molecules:
 amylose (normally 20-30%)
 amylopectin (normally 7080%).


See page 224

Amylose- long narrow lines
Amylopectin- multiple
branches
The main function of starch is
to provide long term energy.
 Amylose starts being digested
in your mouth.
 Amylase enzyme is present in
your saliva.


Starch is composed of
molecules of glucose,
which are broken
down releasing heat
and energy (ATP).
Starch is:
 a versatile
 Cheap
 used as a thickener
 water binder
 emulsion stabilizer
 gelling agent.
 Used for “Carbo Loading”
Carbohydrate Loading
Carbohydrate
loading aims to
maximize muscle
glycogen stores
before endurance
exercise.
Basically, athletes exercising
continuously for 90 minutes or
more at a high intensity will
benefit from carbohydrate
loading.

Athletes exercising for
shorter periods or at lower
intensities do not need
special carbohydrate loading
strategies - just continue
with your usual
carbohydrate-focused eating
How Not To Carbo Load!
Fiber
Not digested by the body




20-35 gms fiber per day
Absorbs water helping to
transport food through the
intestines
Foods- whole grains, fresh
fruits and vegetables, dried
fruits, nuts
Fiber- servings of




fruit and vegetables x 1.5 gm=
Refined grains
x 1.0gm=
Whole wheat grains x 2.5gm=
Legumes, nuts, seeds individual
2 Types of Fiber
Soluble Fiber - Dissolves in water.
Upon ingestion, some soluble fiber
(pectins, beta-glucans, some gums like
guar gum, and mucilages like psyllium)
form viscous or gelatinous solutions in
your stomach and intestines, which
allows for the following:
•Slower emptying of the
stomach
•Delayed absorption of
some nutrients and sugars
in the small intestine
•Lower serum cholesterol
Insoluble Fiber - Does not
dissolve in water.
 Here are the benefits of
insoluble fiber:
 Holds water you consume in
the food.

Helps you absorb minerals,
nutrients, and some short
chain fatty acids.

Allows the bacteria in your
intestine to eat more and
multiply

which increases stool bulk
(over 50% of the stool
volume is bacteria). The
increased bulk promotes
peristaltic action so that
you can eliminate.

Let's see what happens when you eat
refined carbohydrates that have been
stripped of fiber:
•You have a
meal containing
refined
carbohydrates
(cereal, for
example).
•
The carbohydrates are
absorbed quickly and
enzymes break them down.
When you break
carbohydrates down quickly, it
increases the sugar going to
your liver.
•If you have elevated blood
sugar (glucose), it signals
your pancreas to put out
more insulin than it should
be putting out.
•Insulin is a hormone that
regulates carbohydrate
metabolism.
•At lunchtime,
you eat a piece
of cake, which is
a refined
carbohydrate
also high in
sugar.
•This turns to
sugar quickly
and is absorbed
into your gut
lining, goes into
your liver.
•Your liver
sends signals
to your
pancreas that,
if it could
speak, would
be saying,
"Whoa, flooded
with sugar!"
•Your
pancreas
sends out
more
insulin.
The problem with most
processed foods is
that they have low (or
no) fiber and also
contain sugar.
Insulin stays in your body for 5
hours and since you typically eat
again before that 5 hours is up,
you continue to keep your
baseline insulin up and spike it
higher with each meal.
This is important because the negative
side of too much insulin is increased
fat storage and increased
inflammation.
Eventually, the insulin receptors
become resistant…it's like they are no
longer listening when your cells and
liver start screaming "let the sugar in
the cells!"
They can shut down
completely or work
inefficiently.
Sugar can no longer be
normally absorbed, so it goes
back to the liver, which cries
out to the pancreas again to
put out more insulin.
This is a common
cycle that can
lead to obesity.