week 9 : measure resistance of sugar in mineral water

objective: to measure resistance sugar in mineral water. During the experiment, the resistance value can be observe.

Steps:

1. one cup of mineral water.
2. put 1 teaspoon of sugar in the cup and stir it well then measure the resistance.
3. repeat step 2 until 5 teaspoon of sugar been measure.

Result: the resistance value increase when each spoon of sugar been pour in the mineral water.

Spoon	ohms
0	0
1	2
2	3
3	4
4	4
5	5

conclusion : from the experiment, sugar dissolves in water because when a sucrose molecule breaks from the sugar crystal, it is immediately surroundedby water molecules. The sucrose has hydroxyl groups that have a slight negativecharge. The positive charge of the oxygen found in the water molecule bindswith the sugar. As the hydration shell forms around the sucrose molecule.

Week 8: Info about GI

The glycemic index (GI) is a numerical system of measuring how much of a rise in circulating blood sugar a carbohydrate triggers–the higher the number, the greater the blood sugar response. So a low GI food will cause a small rise, while a high GI food will trigger a dramatic spike. A list of carbohydrates with their glycemic values is shown below. A GI is 70 or more is high, a GI of 56 to 69 inclusive is medium, and a GI of 55 or less is low.

The glycemic load (GL) is a relatively new way to assess the impact of carbohydrate consumption that takes the glycemic index into account, but gives a fuller picture than does glycemic index alone. A GI value tells you only how rapidly a particular carbohydrate turns into sugar. It doesn't tell you how much of that carbohydrate is in a serving of a particular food. You need to know both things to understand a food's effect on blood sugar. That is where glycemic load comes in. The carbohydrate in watermelon, for example, has a high GI. But there isn't a lot of it, so watermelon's glycemic load is relatively low. A GL of 20 or more is high, a GL of 11 to 19 inclusive is medium, and a GL of 10 or less is low.

Foods that have a low GL almost always have a low GI. Foods with an intermediate or high GL range from very low to very high GI.

Both GI and GL are listed here. The GI is of foods based on the glucose index–where glucose is set to equal 100. The other is the glycemic load, which is the glycemic index divided by 100 multiplied by its available carbohydrate content (i.e. carbohydrates minus fiber) in grams. (The "Serve size (g)" column is the serving size in grams for calculating the glycemic load; for simplicity of presentation I have left out an intermediate column that shows the available carbohydrates in the stated serving sizes.) Take, watermelon as an example of calculating glycemic load. Its glycemic index is pretty high, about 72. According to the calculations by the people at the University of Sydney's Human Nutrition Unit, in a serving of 120 grams it has 6 grams of available carbohydrate per serving, so its glycemic load is pretty low, 72/100*6=4.32, rounded to 4.