In
this lab we drew dark circles on paper towels. In these circles we
placed small samples of various carbohydrates such as sucrose, starch,
maltose, etc. and labeled the different circles based on what substance we
placed in them. Then, using sucrose as our carbohydrate control,
which we compared the sweetness of all the other carbohydrates to.
In
the lab, there appeared to be a correlation between the number of
sugar rings in the carbohydrate and its degree of sweetness.
For the most
part the monosaccharides appeared to be the sweetest carbohydrates with the
exception of galactose and sucrose. The more sugar rings that there were added
to the monosaccharide, the more bland the carbohydrate appeared to become. For
example, the polysaccharide starch was less sweet than the monosaccharide
fructose. The exceptions to this theory are sucrose, which is
a disaccharide and sweet, and galactose, which is a monosaccharide and not
as sweet.
The
various carbohydrates in this lab relate to several different foods. The
fructose reminded me of fruit not only because of its name, but because the
sweetness of the monosaccharide reminded me of the sweetness normally found in
fruit. The maltose reminded me of cereal because of its grain-like taste and
lactose reminded me of the taste of powdered milk. All of these different
carbohydrates have a place in our food system and are important in helping
our bodies create and store energy.
The sweetest carbohydrates in this lab were monosaccharides
fructose, and glucose, and disaccharide sucrose. As the carbohydrates in the
lab became more complex and formed disaccharides, and polysaccharides, the
carbohydrates became less sweet. The exception to this theory is the
carbohydrate galactose, which is a monosaccharide but is less sweet than all
the other monosaccharides in the lab.
Another characteristic of the carbohydrates in this lab was that
as more sugar rings were added to the carbohydrate, the more powdery the
texture was. Monosaccharides and sucrose and maltose had a granular texture,
while the other disaccharides and polysaccharides had a powdery texture.
The testers did not all give the same rating. Some reasons for
this could be that the testers still had the taste of one carbohydrate in their
mouths so that the taste of that carbohydrate may influence the way another
carbohydrate may taste. Another reason a tester may not give the same rating as
others is if he/she is sensitive to sugar or bland food. For example, a person
who eats oatmeal for every meal every day without any toppings may say that a lollipop
tastes extremely sweet, while a person who has two or three lollipops a day may
say that lollipops are not as sweet as the person who eats oatmeal says. This
is because the person who eats lollipops is so used to the high amount of sugar
that they think it is normal. Lastly, knowing what they taste in advance may
influence testers. If a person expects a carbohydrate to taste a certain way,
that could determine how sweet or not sweet they think it actually is.
The monosaccharides in this lab are similar not only by their
shape, but also by their role in the human body. Almost all of the
monosaccharides store and create energy in the human body and all three
monosaccharides (fructose, glucose, and galactose) help the metabolism.
Carbohydrate structure could determine if the cell uses the
carbohydrate for structural support in the body, or for creating energy, or for helping store fat
and/or energy.
My original hypothesis was “If sucrose tastes sweet with its
granular texture, then all carbohydrates with granular textures will taste
sweet.”
For the most part my hypothesis was correct most of the
carbohydrates with granular textures tasted sweeter than the carbohydrates with
powdery textures. The only exception to my hypothesis was the carbohydrate
maltose that had a granular texture, but did not taste as sweet as the others.
Humans taste sweetness by the taste cells that they have in their taste
buds. When eating, a certain amount of these taste cells will respond to
sweetness while others will respond to sour, salty, bitter tastes, etc. A human
might have more or less of these taste cells respond to sweetness, which is
why tester opinion may vary.
