The Effect of Galactosidase
on Complex Sugars


Mr. Jones
Biology OAC

Cheryl Jones
Sarah Sitch
Jenn Lark

October 16, 1998.


An enzyme is much like a catalyst in that they both accelerate chemical reactions in cells.
Two important factors that influence enzyme activity are temperature and levels of acidity, which can denature the enzyme, breaking the ‘lock and key' formation, causing the enzymes to not fit the substrates anymore (Raven, 1988).

We have chosen to study the effects of galactosidase, an enzyme found in Beano, on complex sugars. Galactosidase aids the decomposition of complex sugars into simple sugars to help prevent gas (Curtail, 1998). Foods such as beans, vegetables, nuts and grains contain indigestible sugars, such as stachyose, verbascose and raffinose (Curtail, 1998). We plan to test this enzyme on beans, pasta, starch and onions to see if the complex sugars had broken down after adding Beano. We will measure the level of glucose in the products, since polysaccharides are formed from glucose or isomers of glucose (Raven, 1988). Foods such a starch form long chains of glucose, making them relatively insoluble.

There are two tests will be using for the presence of glucose; Benedict's solution and Tes tape. In the presence of glucose or ‘reducing sugars', Benedict's blue colour will change to any of the following colours when heated: green, yellow, orange, or red. This colour change is due to the glucose's reaction with the copper sulphate in the Benedict's solution, converting the copper sulphate to copper oxide, a red compound (Crawford, 1983). Tes tape will give us a level of concentration of glucose, by means of a colour change. As the level of glucose increases, the green colour shown on the Tes tape will become darker. Each shade of green refers to a different concentration of glucose, which can be measured by a colour change scale.

Beano is a product used to prevent gas caused by the fermentation of indigestible sugars in the intestine. The enzyme in Beano, alpha-galactosidase, acts on the sugars before they become a problem, by breaking down the indigestible polysaccharides into digestible monosaccharides (Curtail, 1998).


If we add Beano, containing the enzyme galactosidase to foods containing complex sugars, then the complex sugars will break down to form simple sugars.

- Beano
- onions
- pasta
- starch
- beans
- water
- 8 beakers
- wooden splints
- Benedict's solution
- Tes tape
- hot plates
- graduated cylinder


1. Put 25mg of each pureed food (pasta, onions, beans and starch) into 8 beakers (two for each).
2. Add 200mL of water to each.
3. Bring each to a boil. This is to cook the foods so that they are tested the same way we would normally eat them.
4. Wait for the solutions to cool down. This is done because galactosidase does not work in high temperatures.
5. Stir both and wait 2 minutes.
6. Test for glucose with Tes tape and record results.

7. Add Benedicts solution to each and heat gently. Record results.


Tes tape results Benedict's solution colour change
Onions ˝ % concentration of glucose immediately turned onion solution bright green, then went brownish orange
Onions and Beano ˝ % concentration of glucose same as without Beano
Beans 0 % concentration of glucose no change
Beans and Beano 1/10% concentration from light green to orangey green (moss coloured)
Pasta 1/10 % concentration turned a yellowy brown colour
Pasta and Beano 1/10 % concentration same as without Beano
Starch 0 % concentration translucent aqua marine

Starch with Beano 1/10 % concentration from aqua marine to orange. It is no longer translucent, but is thick

In each case, except for the onion solution which stayed the same, the solution containing the Beano was much smoother looking and uniform


Upon testing the effects of alpha-galactosidase on complex sugars, we have come up with interesting discoveries. Our hypothesis stated that if we add Beano, then the complex sugars will be broken down into simple sugars, which was partially true. There was an obvious change between the levels of glucose of starch and beans with Beano and of starch and beans without Beano. This proves that there was more glucose in the solution after we added the enzyme. Therefore, the complex sugars in starch and in beans were broken down into simple sugars. We could not tell, though if there were complex sugars that were broken down in the pasta and the onions. The results show that there are levels of glucose in both onions and pasta before adding Beano and after adding Beano, so we cannot prove that complex sugars