Extracting carbohydrates from food dissolved in hydrochloric acid

[bobdavis]

I know that food is dissolved in hydrochloric acid in the stomach, and carbohydrates are eventually extracted for use in cellular respiration which if I understand correctly is essentially a complex combustion reaction, using oxygen and releasing CO2.

Outside the stomach, I can partially simulate the process of digestion by putting food into a hydrochloric acid solution. Is there a way to extract combustible carbohydrates from the reaction products? It doesn't necessarily need to mirror the actual processes used by the body or be energy efficient, it's just for a fun science experiment for kids

 

[berkeman]

it's just for a fun science experiment for kids

What concentration of hydrochloric acid will these kids be working with?

 

[bobdavis]

If I understand correctly the concentration in the stomach is ~0.16 M/L, but also I'm not necessarily intending for kids to actually work with the acid, just to show

 

[chemisttree]

There is a demonstration of starch conversion to sugar using iodine. Iodine turns blue in the presence of starch and remains orange in the presence of sugars. This demo relied on the amylase enzyme in saliva. A couple of drops of iodine onto a Saltine cracker turns blue but if the student chews the cracker first and let's the mush set a bit, adding a couple of drops of iodine remains orange.

Remember not to ingest iodine!