INT1 Task 3 Exemplar
Does More Sugar Make Lemon Sauce Runny?
Project Design Plan
Cornstarch is a common thickening agent in cooking. Plant starch is made of a mixture of amylose and amylopectin. When heated in a water-based solution, the starch molecules can unwind and then form new hydrogen bonds with other starch molecules, making a network of long molecular filaments that can hold water molecules in a gel (Holmes, 2012). The Argo Cornstarch website warns that too much sugar can interfere with thickening (Argo, 2012).
There are many different ways to thicken liquids and thickening liquids has many applications. Many experiments have been done to test ...view middle of the document...
The runniness of the three sauces will then be measured by allowing them to run down a tilted cookie sheet.
Experimental Design Steps
Lemon sauce will be made six different times as follows:
1. Sugar is mixed with cornstarch thoroughly in the sauce pan to make a homogenous mixture
a. First time, 2 Tablespoons cornstarch and ½ cup sugar
b. Second time 2 Tablespoons cornstarch and ¼ cup sugar
c. Third time 2 Tablespoons cornstarch and 1 cup sugar
d. Fourth time, 2 Tablespoons cornstarch and ½ cup sugar
e. Fifth time 2 Tablespoons cornstarch and ¼ cup sugar
f. Sixth time 2 Tablespoons cornstarch and 1 cup sugar
2. 3/4ths cup water is stirred into the sugar/starch mixture, a little at a time, to make a homogenous mixture
3. Heat is applied to the mixture (stove set at 4) stirring constantly.
4. When the mixture begins to boil, as noted by large bubbles rising to the top, the kitchen timer is started.
5. At 1 minute after boiling begins, the stove is turned off. 2 Tablespoons butter is added and the mixture stirred for 2 minutes.
6. 1/4th cup lemon juice is added and the mixture is stirred for 1 minute.
7. The mixture is transferred to a glass bowl.
8. All cooking materials are thoroughly washed and then rinsed in warm water, then in cold tap water to assure a consistent temperature for each repetition.
9. The sauces are allowed to set at room temperature, stirring occasionally until all three are the same temperature as measured by with the kitchen thermometer after mixing the sauces up with the wooden spoon to make sure they are homogenous.
10. The runniness of the sauces is then measured by letting them run down a cookie sheet and recorded. The average is calculated for sauces with the same sugar content.
Since typical recipes for lemon sauce call for ½ cup of sugar for every 2 Tablespoons of cornstarch, repeating the recipe with half as much sugar and twice as much sugar should give a good estimation of how important the sugar to cornstarch ratio is in the runniness of the sauce. Measuring all six sauces at once should be better than measuring them one at a time, since it will be easier to make sure all conditions are the same for all 6, except for time the sauces have set at room temperature, which can’t be avoided without a bigger kitchen and more assistants. By making sure they are all the same temperature and by stirring them up immediately before measuring, differences measured should be primarily due to the different sugar content.
Sequence of Events
The runniness of the sauce is determined by how far ½ teaspoon of the sauce would run down a cookie sheet tilted at approximately 5 degrees.
1. All sauces are determined to have reached the same temperature using the kitchen thermometer
2. ½ teaspoon of each sauce is placed on the cookie sheet, flat on the countertop, making note of which sauce...