Variation in the Structure and Properties of Carbohydrates
Purpose: What are the differences in the structures of some common carbohydrates? What are the differences in texture and taste of different carbohydrates? How does their structure affect their characteristics?
Materials:
Materials:
Procedure
Part I:
- Use the internet to find the structure and function of each of the molecules being tested in the materials list. Use the "D" form of the structure. Use the "right-handed" form of the structure as well.
- Draw a structural diagram of each molecule, showing the specific arrangement of atoms in the molecule. Next to each drawing, write a short description of the main functions of the molecule and its structure. Include bibliographical reference information.
Part II:
- Scoop a bit of sucrose onto a spoon. Use this for the test and then discard the spoon in the trash. Do no return samples to the stock dishes.
- Touch your finger to the sucrose. Touch the sucrose to your tongue and take 10s to note its sweetness. Let this amount be a standard of 100 on a scale from 0 to 200. Predict their sweetness based on their structures.
- Describe the texture of the sucrose
- For each carb, use a new spoon and repeat steps 1 through. Rank the sweetness of each carbohydrate based on the scale.
- Record the received data into a data table.
Results:
lab2e1.docx | |
File Size: | 5 kb |
File Type: | docx |
Analyzing and Concluding:
From the experiment we found several things. Certain substances turned out to be much sweeter than some of the other ones. For example: Fructose was about a 170/200 while starch was given a 0/200. We found that some of the substances were monosaccharides, others Disaccharides, and some were polysaccharides. From the data we can see that the monosaccharides tended to have a higher sweetness, then came disaccharides and polysacchrides at the bottom. Looking at the structures of each substance, we can see that as the molecular structure decreases, the sweetness of it increases. Thus, complex saccharides are less sweet. What also seemed to change the sweetness of the carbohydrates was its texture. The more fine and powdery it was the less sweet it seemed. I think it is like that because they would dissolve faster and therefore last very shortly for the sweetness, so it's hard to tell that it is even sweet. Our data may not be entirely correct, due to some flaws in it from simple human error, but there is a decent correlation between their structures and their sweetness.
From the experiment we found several things. Certain substances turned out to be much sweeter than some of the other ones. For example: Fructose was about a 170/200 while starch was given a 0/200. We found that some of the substances were monosaccharides, others Disaccharides, and some were polysaccharides. From the data we can see that the monosaccharides tended to have a higher sweetness, then came disaccharides and polysacchrides at the bottom. Looking at the structures of each substance, we can see that as the molecular structure decreases, the sweetness of it increases. Thus, complex saccharides are less sweet. What also seemed to change the sweetness of the carbohydrates was its texture. The more fine and powdery it was the less sweet it seemed. I think it is like that because they would dissolve faster and therefore last very shortly for the sweetness, so it's hard to tell that it is even sweet. Our data may not be entirely correct, due to some flaws in it from simple human error, but there is a decent correlation between their structures and their sweetness.
Reflection:
This was a really fun lab to do. Not only did we get to eat some things, but it was exciting to find out which ones tasted really god and not so good. It kind of reminds me of eating jellybeans without looking at them and not knowing what you're going to get. I found it also funny that I graded the fructose very high and I was surprised by how sweet it was. I found out later that it is common in a syrup used to sweeten foods, and I was surprised I had never heard about it. My group mates were great, and it only made the experience more enjoyable.
This was a really fun lab to do. Not only did we get to eat some things, but it was exciting to find out which ones tasted really god and not so good. It kind of reminds me of eating jellybeans without looking at them and not knowing what you're going to get. I found it also funny that I graded the fructose very high and I was surprised by how sweet it was. I found out later that it is common in a syrup used to sweeten foods, and I was surprised I had never heard about it. My group mates were great, and it only made the experience more enjoyable.