Topic 15

CarbohydratesCarbohydrates

andand

Related SubstancesRelated Substances

A Balanced Diet A balanced diet is the correct mixture and amount A balanced diet is the correct mixture and amount

of the five food groups.of the five food groups. They are: They are: Proteins e.g.Beans, meat & poultryProteins e.g.Beans, meat & poultry Fats e.g.Cheese milk & butterFats e.g.Cheese milk & butter Carbohydrates: Pasta, rice and cakes.Carbohydrates: Pasta, rice and cakes. Vitamins:e.g. A,B,B12,C,E&DVitamins:e.g. A,B,B12,C,E&D Minerals:e.g.Ca,Fe, Zn & I etc.Minerals:e.g.Ca,Fe, Zn & I etc.

Carbohydrates

Carbohydrates are made up of three Carbohydrates are made up of three elements only i.e. Carbon, hydrogen and elements only i.e. Carbon, hydrogen and oxygen.oxygen.

They have a General Formula of(C)x(HThey have a General Formula of(C)x(H22O)yO)y

Carbohydrates provide our bodies with Carbohydrates provide our bodies with energy.energy.

There are 3 groups of CarbohydrateThere are 3 groups of Carbohydrate

1. Monosaccharides (the simplest sugars) e.g. Glucose and Fructose, both have formula C6H12O6 ie Isomers

2.Disaccharides e.g Sucrose & Maltose(made from two monosaccharides joining together)

3. 3. Polysaccharides ( made up many monosaccharides joining together)

eg Starch & Cellulose.

Approx 300 glucose units join together to make Starch. They join together by means of a CONDENSATION Reaction i.e.the removal of water molecules between monosaccharides. The Formula of starch is -(C6H10O5)n-

Breaking Carbohydrates Up

Monosaccharides join by Monosaccharides join by the removal of water the removal of water molecules .i.e. molecules .i.e. Condensation Reaction.Condensation Reaction.

To break up Carbohydrates we ADD water.This is called Hydrolysis.Hydrolysis.

Instead of water our bodies use Hydrochloric Acid

Starch

Glucose molecules

Digestion of Food

For us to receive the benefit of food it must be For us to receive the benefit of food it must be absorbed into our absorbed into our bloodstream.

Digestion happens in a number of stages:Digestion happens in a number of stages: First broken down in mouth by chewing and use ofFirst broken down in mouth by chewing and use of

EnzymesEnzymes in saliva. in saliva. Passes down gullet into stomach where Passes down gullet into stomach where HydrolysisHydrolysis

begins (stomach contains Hydrochloric Acid).begins (stomach contains Hydrochloric Acid). Begins long journey through Small IntestineBegins long journey through Small Intestine(22-26ft) (22-26ft) and and

then into large intestine(then into large intestine(4-6ft4-6ft) where it finally ) where it finally absorbedabsorbed into the into the blood.blood.

Digestion (continued)

The large Intestine or Gut can be regarded a long The large Intestine or Gut can be regarded a long tube which contains tiny pores. tube which contains tiny pores.

For the food to get through to the other side i.e. the For the food to get through to the other side i.e. the bloodstream the food molecules must be broken up bloodstream the food molecules must be broken up into small enough units.into small enough units.

For example Starch must be broken into Glucose For example Starch must be broken into Glucose molecules. molecules.

Alkanols (Alcohols)

The Alkanols are another Homologous series with General The Alkanols are another Homologous series with General Formula Formula CCnnHH2n+12n+1OHOH

Alkanols are generally used as solvents and cleaning agents.Alkanols are generally used as solvents and cleaning agents. Ethanol is the alkanol that is present in all alcoholic drinks.Ethanol is the alkanol that is present in all alcoholic drinks. It is made by a process called It is made by a process called FermentationFermentation in which sugar is in which sugar is

turned into alcoholturned into alcoholC6H12O6 C2H5OH + CO2 yeast

Yeast acts as a Catalyst since it contains Enzymes (a Biological Catalyst) which will only work at a specific pH and Temperature

The mixture is finally DISTILLED to increase the alkanol concentration