Download Chapter 15 Review of Carbohydrates

The Chemist’s View of Carbohydrates
0 What three elements are carbohydrates made of?
0 carbon, hydrogen and oxygen
0 What are the two types of carbohydrates?
0 Simple – sugars
0 Complex – starch and dietary fiber
The Simple Carbohydrates
0 Monosaccharrides are single sugars
0 What are the three sugars that are monosaccharrides -
page 221
0 Glucose – basic sugar
0 Fructose – found in fruits and tree sap
0 Galactose – not found in nature, but is bonded to
something else
0 Disaccharides sugars made of two monsaccharides
bonded together.
0 What are the two most common sugars found in food. Page
221
0 Sucrose
0 Lactose – found in milk
The Complex Carbohydrates
0 Few or many glucose units bound/linked together in
straight or branched chains.
Complex Carbohydrates
0 Glycogen
0 Storage form of glucose in the body
0 Provides a rapid release of energy when needed
0 Starches
0 Storage form of glucose in plants
0 Found in grains, tubers, and legumes
0 Lactose Intolerance
0 Symptoms include bloating, abdominal discomfort,
and diarrhea.
0 Causes include lactase deficiency due to a natural
decrease that occurs with aging or damaged
intestinal villi.
Carbohydrates in the Body
0 Used and stored by the body
0 Help supply the body with a steady stream of energy.
0 What percentage of your daily calories should come from
carbohydrates?
0 55-65% (or about 60%)
Energy Production
0 Carbohydrates are efficient fuel for the body.
0 What is the ratio of digested carbohydrates to kcalories
of energy – page 226
0 1 g to 4kcalories
Diabetes
0 What is the main carbohydrate found in blood? Refer to
page 226 for answer.
0 Glucose, blood sugar
0 It affects the health and functioning of all the body’s
cells. What is it most critical for? Page 226
0 Brain and nervous system.
0 Blood Glucose Levels
0 Pancreas monitors the flow of glucose to the cells.
0 Name the hormone secreted by the pancreas. Page 227
0 Insulin
0 Signals the body’s cells to accept the surge of nutrients that
have entered the blood.
0 Helps keep glucose in the blood at a normal level.
0 What are the two conditions related to diabetes?
Pages 227 – 228
0 Hyperglycemia –abnormally high blood glucose level.
0 Hypoglycemia – abnormally low level of blood glucose.
Hyperglycemia Can Cause Serious
Long-Term Problems
Hypoglycemic Symptoms
Diabetes
0 Prevalence of Diabetes: 25.8 million adults in
US
0 Metabolic Syndrome: Risk factors related to
obesity.
0 What are the three types of diabetes? Page 227
0 Type I: pancreas secretes little or no insulin, occurs in
children or young adults.
0 Type II: most common, accounts for over 90% of all
cases. Pancreas produces insulin, but either not enough
or the insulin can’t be used effectively.
0 Gestational Diabetes: High sugars in Pregnancy.
Pathophysiology of
Diabetes
When you eat, your body
breaks food down into
glucose. Glucose is a
type of sugar that is
your body’s
main source
of energy.
Pathophysiology of
Diabetes
As blood glucose
rises, the body
sends a signal to
the pancreas, which
releases insulin.
Blood glucose regulation
Blood glucose
goes up and down
throughout the
day:
 As your blood
glucose rises
(after a meal), the
pancreas releases
insulin.
Type 2 diabetes
Your pancreas may not
produce enough insulin
(insulin deficiency).
Your cells don’t use
insulin properly.
The insulin can’t
fully “unlock” the
cells to allow
glucose to enter
(insulin resistance).
Risk factors for type 2
diabetes
Type 2 is more common in people who:
 Are overweight.
 Are 45 or older.
 Are physically inactive.
 Have a parent or sibling with type 2
diabetes.
 Are African American, Native American,
Hispanic American, or Pacific Islander.
 Have abnormal cholesterol levels.
 Have had gestational diabetes, or given
birth to a baby greater than 9 lbs.
 Have high blood pressure.
Carbohydrates in Food
Production
0 Add taste and texture to many food products.
0 Valued for sweetness.
0 Glucose most common monosaccharide in foods.
Sweeteners
What is the first thing that comes to mind when you
think of sweeteners?
List other sweeteners that you can think of.
0 Table sugar = sucrose: extracted from sugar cane or
sugar beets.
0 Brown sugar – granulated sugar flavored with
molasses.
0 Confectioners’ sugar – powdered granulated sugar
with an added anti-caking agent, such as cornstarch.
Sugar Substitutes
Sucralose
- chlorinated sucrose derivative
- body cannot recognize chlorinated carbohydrate
- not absorbed by the body, does not add calories to
diet.
- does not break down with heat.
Aspartame
- an amino acid-based artificial sweetener, approved
by FDA in 1981.
- original form not stable when heated.
- does not promote tooth decay, doesn’t have an after
taste.
Candy Making
Referred to as crystalline – made by crystals formed
from supersaturated sucrose solutions.
Smaller crystals produce a smoother texture and a
superior product.
Sucrose tends to produce larger crystals.
Controlling Crystallization
0 Crystal formation starts when the solution, syrup,
achieves the proper concentration of sugar.
0 Concentration is measured by the boiling point.
0 Interfering agents – added to a sugar syrup to control
crystal growth. Cream of tarter, vinegar, corn syrup.
0 Agitation, stirring or beating the solution