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CarbohydratesCarbohydrates
Are organic compounds and the body’s main Are organic compounds and the body’s main source of energysource of energy
Carbon + hydrogen + oxygenCarbon + hydrogen + oxygen Our sources of carbohydrates are plants, fruits, Our sources of carbohydrates are plants, fruits,
vegetables, grainsvegetables, grains
PhotosynthesisPhotosynthesis
Chlorophyll + sunlight = glucoseChlorophyll + sunlight = glucose Plants use carbon dioxide and water and sunlight to Plants use carbon dioxide and water and sunlight to
create glucose and oxygencreate glucose and oxygen We eat the glucose, and breathe the oxygen and We eat the glucose, and breathe the oxygen and
release carbon dioxide and water vaporrelease carbon dioxide and water vapor Chlorophyll is the green pigment in plantsChlorophyll is the green pigment in plants Glucose is the basic sugar molecule from which all Glucose is the basic sugar molecule from which all
other CHOs are builtother CHOs are built A plant can convert glucose into other sugars, A plant can convert glucose into other sugars,
starches and fibersstarches and fibers
The Simplest CarbohydratesThe Simplest Carbohydrates
The simplest carbohydrates are the sugarsThe simplest carbohydrates are the sugars They are a natural part of many foodsThey are a natural part of many foods They have a sweet tasteThey have a sweet taste can be extracted from plants and used to sweeten can be extracted from plants and used to sweeten
candy, pop and baked goodscandy, pop and baked goods Simple carbohydrates exist in their pure form as Simple carbohydrates exist in their pure form as
crystalline solidscrystalline solids Eating too many simple sugars can lead to health Eating too many simple sugars can lead to health
problemsproblems Sugars are also called SACCHARIDESSugars are also called SACCHARIDES
CHO= Sugars + Starches + FibersCHO= Sugars + Starches + Fibers
Simple Sugar Molecule has 6 C, 12 H and 6 OSimple Sugar Molecule has 6 C, 12 H and 6 O It is a six sided ring (more stable form) It is a six sided ring (more stable form)
containing a hydroxyl group (combination of containing a hydroxyl group (combination of hydrogen and oxygen containing one atom of hydrogen and oxygen containing one atom of each (OH)each (OH)
The “-” is a chemical bond that attaches the The “-” is a chemical bond that attaches the groupgroup
Types of Simple SugarsTypes of Simple Sugars
There are two types of simple sugars:There are two types of simple sugars: MonosaccharideMonosaccharide DisaccharidesDisaccharides The three examples of monosaccharides are The three examples of monosaccharides are
glucose (buuilding blocks for all other sugars) glucose (buuilding blocks for all other sugars) fructose (fruits and tree sap) and galactose fructose (fruits and tree sap) and galactose (usually bonded to something else…some are (usually bonded to something else…some are found in milk products)found in milk products)
disaccharidesdisaccharides
Are made from 2 monosaccharides bonded togetherAre made from 2 monosaccharides bonded together Three examples of disaccharides are sucrose (table Three examples of disaccharides are sucrose (table
sugar), lactose in milk (glucose and galactose stuck sugar), lactose in milk (glucose and galactose stuck together) and maltose (commonly found in cereals…2 together) and maltose (commonly found in cereals…2 glucose molecules)glucose molecules)
ALL carbohydrates (whether simple or complex) are ALL carbohydrates (whether simple or complex) are broken down into monosaccharides when digestedbroken down into monosaccharides when digested
4 Properties of Sugar4 Properties of Sugar
While sugars have the same chemical formula, While sugars have the same chemical formula, they differ as to how they are positioned in the they differ as to how they are positioned in the molecule ringmolecule ring
The four properties are sweetness, The four properties are sweetness, caramelization, solubility, and crystalizationcaramelization, solubility, and crystalization
Property 1- SWEETNESSProperty 1- SWEETNESS
Some sugars are sweeter than othersSome sugars are sweeter than others Order of sweetness: fructose, sucrose, glucose, Order of sweetness: fructose, sucrose, glucose,
galactose, maltose and lactosegalactose, maltose and lactose The sweetness depends on concentration, The sweetness depends on concentration,
consistency, temperature, and pH level, and consistency, temperature, and pH level, and how the molecules fit at the taste bud siteshow the molecules fit at the taste bud sites
Sugar in Processed FoodSugar in Processed Food
½ cup of canned corn: 3 tsp½ cup of canned corn: 3 tsp 12 oz cola: 8 tsp12 oz cola: 8 tsp 1 tbsp ketchup: 1 tsp1 tbsp ketchup: 1 tsp 1 small yogurt: 7 tsp1 small yogurt: 7 tsp 2 oz chocolate: 8 tsp2 oz chocolate: 8 tsp
Property 2- CaramelizationProperty 2- Caramelization
This is the browning reaction that can occur This is the browning reaction that can occur with any kind of sugar when heated. Sugars with any kind of sugar when heated. Sugars differ at what temperature this occursdiffer at what temperature this occurs
As sugar is heated, water leaves the molecule. As sugar is heated, water leaves the molecule. At high temperatures the molecule remnants At high temperatures the molecule remnants join to form larger molecules with a higher join to form larger molecules with a higher concentration of carbon, which creates the concentration of carbon, which creates the distinctive caramel colordistinctive caramel color
Property 3: SolubilityProperty 3: Solubility
The ability of sugar to dissolve in water mirrors their The ability of sugar to dissolve in water mirrors their sweetnesssweetness
Order of solubility: fructose (most soluble), sucrose, Order of solubility: fructose (most soluble), sucrose, glucose, galactose, maltose and lactoseglucose, galactose, maltose and lactose
Solubility is affected by water temperature (heat Solubility is affected by water temperature (heat increases it)increases it)
Supersaturation: solution that holds more dissolved Supersaturation: solution that holds more dissolved solute than it would normally hold at that temperaturesolute than it would normally hold at that temperature
Property 4: CrystallizationProperty 4: Crystallization This is beneficial in candy makingThis is beneficial in candy making Water evaporates increasing the amount of sugar when you are Water evaporates increasing the amount of sugar when you are
boiling the sugar solution at high temperatures.boiling the sugar solution at high temperatures. When it reaches a certain temperature, crystallization occurs. When it reaches a certain temperature, crystallization occurs.
Crystals separate from solution each in a unique pattern of Crystals separate from solution each in a unique pattern of moleculesmolecules
The size of the crystals depends on how many particles are The size of the crystals depends on how many particles are present and how quickly crystals grow around thempresent and how quickly crystals grow around them
A larger # of particles = smaller crystalsA larger # of particles = smaller crystals Rapidly growing crystals = smallerRapidly growing crystals = smaller Size also depends on the type of sugar (sucrose = large Size also depends on the type of sugar (sucrose = large
crystals and glucose and fructose = relatively small)crystals and glucose and fructose = relatively small)
The Complex Carbohydrates: The Complex Carbohydrates: Starches and FibresStarches and Fibres
Starches: plant foods, taste rather bland, stored Starches: plant foods, taste rather bland, stored in granular formin granular form
Fibre: gives plants their structure (cellulose, Fibre: gives plants their structure (cellulose, pectins, gums, bran- which is the most pectins, gums, bran- which is the most concentrated form of fibre)concentrated form of fibre)
There are also peas, lentils, corn, potatoes, dry There are also peas, lentils, corn, potatoes, dry beans, grain products (such as rice, pasta and beans, grain products (such as rice, pasta and breads)breads)
PolysaccharidesPolysaccharides
Complex CHOs are polysaccharides or large Complex CHOs are polysaccharides or large molecules made of many simple glucose unitsmolecules made of many simple glucose units
Polysaccharides are made of chemically linked Polysaccharides are made of chemically linked monosaccharides (there may be 10…there may monosaccharides (there may be 10…there may be 10,000) be 10,000)
A polysaccharide is an example of a A polysaccharide is an example of a polymer…which is a large molecule formed polymer…which is a large molecule formed when small molecules of the same kind chain when small molecules of the same kind chain together togethertogether together
StarchesStarches
Are literally plant foodAre literally plant food They are to plants what glycogen is to people They are to plants what glycogen is to people
RESERVE ENERGYRESERVE ENERGY Starches are stored in granular form mostly in Starches are stored in granular form mostly in
seeds and rootsseeds and roots While they are made of chains of sugar While they are made of chains of sugar
molecules they taste bland because of the type molecules they taste bland because of the type of glucose they are made of (alpa-D-glucose)of glucose they are made of (alpa-D-glucose)
Starches have 2 structuresStarches have 2 structures
A) amylose (in this form of starch the A) amylose (in this form of starch the molecules are linear, the are long and narrow molecules are linear, the are long and narrow like a linelike a line
B) amylopectin (in this form molecules have B) amylopectin (in this form molecules have multiple branches like veins in a leaf- typically multiple branches like veins in a leaf- typically more abundant than amylose)more abundant than amylose)
Most starches found in foods have both forms Most starches found in foods have both forms but in differing proportionsbut in differing proportions
StarchesStarches
Starches are really Starches are really important in food important in food preparation as preparation as thickening agents and thickening agents and stabilizersstabilizers
FiberFiber
Is not digested by the bodyIs not digested by the body It is what gives plants their structureIt is what gives plants their structure The main plant fiber in foods in cellulose The main plant fiber in foods in cellulose
which is a polymer made of alpha-D-glucosewhich is a polymer made of alpha-D-glucose Other edible fibers include hemicellulose, Other edible fibers include hemicellulose,
pectins, and algal polysaccharidespectins, and algal polysaccharides
Fiber, continuedFiber, continued
Fiber absorbs water helping to transport food Fiber absorbs water helping to transport food through the intestinesthrough the intestines
Fiber is found in whole grains, fresh fruits and Fiber is found in whole grains, fresh fruits and vegetables dried fruits and nutsvegetables dried fruits and nuts
In order to digest fiber we need the enzyme In order to digest fiber we need the enzyme cellulase. We can not synthesize this enzyme cellulase. We can not synthesize this enzyme in our digestive tracts so we cant digest fiber, in our digestive tracts so we cant digest fiber, but ti does add bulk to our diet to help us feel but ti does add bulk to our diet to help us feel full and also helps us to clean our intestinesfull and also helps us to clean our intestines
PectinsPectins
Are water soluble CHOs that occur naturally Are water soluble CHOs that occur naturally in many ripe fruits and vegetables. They in many ripe fruits and vegetables. They produce a gelatine-like substance used to produce a gelatine-like substance used to thicken jellies. They are also used in food as thicken jellies. They are also used in food as emulsifiers and stabilizers in the food industry. emulsifiers and stabilizers in the food industry. They are very easily oxidated becoming dark. They are very easily oxidated becoming dark. This is why apples, pears and other fruits This is why apples, pears and other fruits quickly brown after you cut them.quickly brown after you cut them.