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CARBOHYDRATES Organic chemistry has given the name
saccharide to all carbohydrates classified as sugars.
Sugar was the common name used before organic chemists developed the system used today
Sugars are organic compounds. That means they contain carbon compounds
All living things are composed of carbon-based (organic) compounds
Carbohydrates Are …
one of the six essential nutrients The body’s main source of energy The sugars The starches The fibers in your diet
Except for the natural sugar in milk, nearly all carbohydrates come from plant sources
Carbohyddrates… …are made of three chemical elements
Carbon Hydrogen Oxygen
These are bonded together to form saccharides – sugar units
How the elements are arranged, determines the type of sugar it is… Monosaccharide Disaccharide Polysacchride
Monosaccharides Sugar in their simplest form Carbohydrate molecules that are
building blocks for more complex carbohydrates
Monosaccharides in Food Glucose – the most prevalent
also called dextrose, grape sugar & corn sugar
Found in fruits, vegetables, honey,
corn syrup, and molasses
FRUCTOSE The sweetest of all the sugars Found in honey, molasses,
fruits & veggies
Galactose
Is produced when lactose(milk sugar) is digested
Or when milk products are fermented (cheese& yogurt)
SUGAR How Sweet It Is
What is it? The white stuff we know as sugar is
sucrose. It’s two simpler sugar stuck together
frutcose & glucose
Also called a….
DISACCHARIDES Contain 2 monosaccharides joined together Sucrose (table sugar) is the most common Glucose + fructose = sucrose
Maltose – formed during the digestion of starch Also found in malted grains – the least sweet
Lactose – sugar found in milk
The body splits disaccharides into monosaccharides during digestion Called hydrolysis Lactase (enzyme)
Glucose & galactose Galactose broken down to
Glucose (in the liver)
Glucose is used for energy
Polysaccharides(Polymers)
Poly = many Mer = parts Polymer = many parts They are long chains of molecules (it gets
complicated!)
Polysaccharide Examples Starch: is the storage form of energy in
plants. Made of many glucose molecules bonded together.
Breads, cereals,
Corn, potatoes, & legumes (dried beans)
Polysaccharide Examples Fiber: Make up the tough fibrous walls of
plants. Not digested by humans Cellulose, gums, pectins Found in: Grain products – bread, cereal,
corn, potatoes, & legumes COMPLEX Carbohydrates
Man-Made Polymers Plastic, nylon, grease
Natural Polymers Cotton, wool, hair, skin Protein, Gelatin Polysaccharides
Sugarand its many disguises
Honey, syrup, corn sugar, corn syrup, molasses, maple syrup, invert sugar, brown sugar, sucrose, fructose, glucose, dextrose, maltose, & lactose
Anything that ends in “ose”
Sugars 6 Functions in Food Prep Sweeteners Preservatives Tenderizers Crystallizing Agent Carmelizing Agent Fermenting Agent
Sweetners Ability to sweeten is its major function in
most foods. Scientists have found the sweeter the sugar
is, the simpler the structure of the molecule is.
The longer the sugar chain is, the less sweet the sugar will seem to be.
Preservatives Sugar helps prevent food spoilage Water is drawn to sugar molecules before it is
drawn to bacteria. Most single-celled contaminants will dehydrate
and die in concentrated sugar solutions Helps products such as cakes stay moist
Tenderizers Sugar interferes with the flour’s ability to
form an elastic structure (Gluten) Compare the tenderness of
An Italian hard roll A piece of white bread A sweet roll or donut
Tenderizers The tenderizing effect of sugar changes the
viscosity or “pourability” of a batter
Crystallizing Agent Sugars ability to dissolve in water increases
as the solution gets hotter. When water evaporates it increases the
sugar concentration Sugar crystals that form on the side of the
pan will trigger more crystallization. Put a lid on it.
Steam will wash the crystals from the sides
Interfering Agents A substance that can prevent or slow
crystal growth. Corn syrup Butter Cream
Caramelizing Agents When exposed to high heat – over a period
of time it changes to brown liquid – caramel.
It is partially responsible for the brown crust on baked goods and toast.
And the distinctive taste and color of caramel candy
SUGAR Solid at room temperature Liquifies when heated – changes from clear
to yellow to brown/black – Called carmelization A chemical process Can be used in many ways
Fermenting Agent Plays a major role in the fermentation of
wine, beer and yeast breads. Sugar is the food supply for the
microorganisms involved in the process.
Promotes carbon dioxide production in yeast
Acts a a dehydrating agent in pectin gel formation (jam & jellies)
Lowers freezing point of mixtures (ice cream)
Increases boiling point of mixture (candy)
Part 1
The End
Part 2
Simple SugarsAnd yourHealth
Refined Sugars Sugars can be divided into 2
groups Sugar that occurs naturally in foods
* milk & fruit Sugars added to foods during
processing or at the table. Called REFINED SUGARS
Refined Sugars Are… Sweeteners separated from their natural
sources for use as food additives. Comes from sugar cane, sugar beets &
corn Used as sweeteners, to increase bulk or aid
browning
Refined Sugars Sources… Soft drinks, candy, cake, cookies, donuts Also… many processed foods such as
catsup, cereal, potato chips and… Reduced fat or fat free products
Added sugar increases the calories in food without increasing the nutrients. (“empty calories”)
In other words…
Sugar Eat too much – have problems
Obesity Diabetes, Bad teeth
Experts recommend keeping sugar intake to no more than 25% of your total calories.
For example: 2000 calorie diet = 500 calories from sugar.
Health Related Questions Is Sugar Bad for your teeth?
Yes! Too much sugar = tooth decay (dental caries) Bacteria feed on the carbohydrate particles & form
plaque that clings to teeth. As bacteria grow they form acid that eats away
tooth enamel, forming pits which can deepen into cavities.
Sticky foods like cookies, crackers, caramels etc. cling to teeth.
They are more harmful than foods that are quickly swallowed.
Carbohydrates eaten at meals are less damaging than between meal snacks because they are removed by beverages and other foods eaten with them.
Do not allow a baby to sleep with a bottle in their mouth.
The acids formed can destroy their teeth After feeding, clean gums and teeth with a
soft, clean cloth
Does sugar cause hyperactivity? Researchers have found no proof… However… Children who eat large amounts of sweets
may be missing important nutrients. Eating a more nutritious diet can improve
performance.
Is sugar addictive? People are born with a preference for
sweet- tasting foods. Researchers think that the need for sugar is
psychological. We eat sweets because we like them – not because we are addicted to them.
Does Too Much Sugar Cause Diabetes? Diabetes mellitus – and inability to use the
hormone insulin. Insulin regulates blood glucose level by
pulling glucose from the bloodstream. When the body does not make enough or
does not use it correctly, glucose builds up in the bloodstream.
Two Types of Diabetes Type I – insulin-dependent
Pancreas does not make insulin Occurs mostly in children & young adults Must take injections to regulate
Type II or noninsulin –dependent Body does not respond well to the insulin that
the pancreas makes Usually occurs in adults over 40 People who are overweight People whose diets are high in refined sugar
and low in fiber Can often be controlled with diet and physical
activity
Hypoglycemia (low blood sugar) Body produces too much insulin and
causes blood sugar to drop sharply 2-4 hours after eating
Avoid eating large amounts of sugar at one time.
Eat at regular intervals
Lactose Intolerance The inability to digest lactose – the
carbohydrate enzyme in milk. Symptoms: gas, cramping, nausea &
diarrhea Occurs most often among nonwhite
populations Develops as people age
May be able to eat milk products such as yogurt, cheese & buttermilk since the lactose is broken down during the culturing process.
Will have to get calcium from other sources.
So…Exactly what carbohydrates should I eat?
Complex Carbohydrates Dividing carbohydrates into simple &
complex makes sense on a chemical level
But doesn’t explain what happens to different carbs inside the body.
Starch in white bread & French fries qualifies as “Complex” – yet the body converts this starch to blood sugar almost as fast as it processes pure glucose
Fructose is a simple carb, but has minimal effect on the blood sugar
Other factors that influence how quickly the carbohydrates raise blood sugar include How much it has been processed Fiber content Ripeness – more ripe=more sugar Fat & acid content. Physical form – finely ground vs. coarsely
ground
For optimal health get your grains intact from Whole wheat bread Brown rice Whole grain pasta Old-fashioned rolled oats
Beans (pinto, black, kidney, garbanzo etc)
Fresh fruit
Fresh vegetables
Take good care of yourself
You are the only “You” that you’ve got!!