Macromolecule Lab Essay

Macromolecule Lab
Standard: Macromolecules are made from a small collection of simple precursors.

Purpose
o To understand the tests for macromolecules in foods.
o To discover the types of nutrients contained in a variety of foods.

Fill in the table.
Macromolecule 
Simple Precursor 
Function

Materials Supplies
(To be taken to your table) (To remain at the supply table)
*6 test tubes *Benedict’s Solution w/dropper
*1 well plate *Lugol’s Solution w/dropper
*Test tube holder *Biuret’s Solution w/dropper
*Paper towels *Hot Water Bath
*Test Tube clamps
* Negative Test Indicators

Procedure
1. Prepare 6 test tubes with food samples.
a. Put a small amount of food at the bottom of the test tube
b. Return to your station
2. Translucency tests lipids
a. Place a dab of food sample on a piece of paper towel.
b. Let each sample dry before checking for translucency.
c. Record any observations.
3. Lugol’s solution tests starch
a. Use a stir stick to put a small drop of EACH food from the test tube into a different well in the Well plate
b. Add a drop of Lugol’s solution to each well.
c. Record any color changes.
4. Biuret solution tests protein
a. Use a stir stick to put a small drop of EACH food from the test tube into a different well in the Well plate
b. Add a drop of Biuret solution to each well.
c. Record any color changes.
5. Benedict’s solution tests sugar
a. Add a dropperful of Benedict’s solution to each test tube.
b. Place the test tube in a hot-water bath.
c. Heat for 5 minutes.
d. Record any color changes.



e. Record whether the sample dried or remained see-through in the Observation section.
Nutrient Foods
Corn White beans White bread Potato chips Peanut butter
Sugar
Starch
Protein
Lipid
Observations – record any color changes or translucency seen.


Data – based on the observations, assign between ++++ for a really positive result or - - -...