Sweetness Lab

          In this lab, we tested for the sweetness of different carbohydrates. The carbohydrates that we tested were sucrose, glucose, fructose, galactose, maltose, lactose, starch, and cellulose. The monosaccharides that we tested were glucose, fructose, and galactose. The disaccharides that we tested were maltose and lactose. The polysaccharides that we tested were starch and cellulose. We rated the different carbohydrates from a scale of 0 - 200. The claim is that if monosaccharides and disaccharides are sweeter than polysaccharides, then fructose, a monosaccharide, will be sweeter than starch, a polysaccharide.
          Carbohydrate structure can affect how they are used by cells and organisms. Monosaccharides, or carbohydrates with one ring, and disaccharides, or carbohydrates with two rings, are used by cells and organisms by using them as quick energy. Polysaccharides, or carbohydrates with three or more rings, are used by cells and organisms as long term energy as they are digested and converted into energy slower than the simple carbohydrates like monosaccharides and disaccharides.
          Not all testers gave the same rating because each person has a different point of view and they taste things differently than other people. Also because of the amount of the carbohydrate that they tasted. One person could have a bigger sample of a type of carbohydrate than another person, causing the taste to be slightly different between each tester, resulting in a different rating. Another factor that could make the ratings different from each tester is that some people are lactose intolerant and cannot consume the lactose that is needed to conduct this lab, so they cannot give an honest rating based on their taste.
          There are many things that cause humans to taste sweetness. There are receptor proteins on the tongue that detect sweetness. When the taste receptor cells that detect sweetness comes in contact with a substance that is sweet, it sends a signal to the brain saying that substance is sweet.

Results and Data:

Carbohydrate	Type of Carb	Rating	Color	Texture	Observations
sucrose	disaccharide	100	white	granular	table sugar
glucose	monosaccharide	150	white	granular	very sweet
fructose	monosaccharide	180	clear	granular	used in most foods
galactose	monosaccharide	75	white	powdery	clumpy
maltose	disaccharide	80	yellow	granular	tastes like sweet potatoes
lactose	disaccharide	50	white	powdery	clumpy
starch	polysaccharide	10	white	powdery	clumpy
cellulose	polysaccharide	0	white	powdery	clumpy and dry