Ask A Scientist© Biology Archive

status       student
age          13

Question -   Im doing my science experiment to see if the processing
of food produces gas. I was told that you do this by getting the
vegitables, grounding them up, mixing them with vinegar and putting it in
a test tube and then place a balloon over it to see if gas is produced.
First I tried mixing the foods (Im using canned, frozen and fresh broccoli
first to see if it works) with the vinegar and put it in a test tube and
I placed a balloon over it but no gas was produced. I then tried it again
in heat and again in the cold and it still wouldnt work.  I tried the
experiment again and pureed the broccoli and mixed it with the vinegar,
put the balloon over it and still no gas was produced. What could I be
doing wrong? Im using 5% acidity vineger because that's the only kind I
could find. Do I need a stronger one? Where can I get a stronger one? How
much vinegar should I be using? How much of the broccoli should I be
using? Do I have to do something to the broccoli first? Please try to
answer my questions I really need help.
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It doesn't seem that you are performing your experiment incorrectly.  Your
only difficulty appears to be that you find your result boring.  You wanted
to know if the processing of food produces gas.  You chose to look at one
particular type of processing of one particular type of food, namely adding
vinegar to broccoli.  (Making broccoli pickles, I guess.)  You found (drum
roll, please) that the process produced no detectable gas.  So there's your
answer - adding vinegar produces no gas, whether it's hot or cold, or
whether the broccoli is fresh, frozen, or canned.

If you really want to make gas of some sort, add acid (such as vinegar or
lemon juice) to baking soda, or add iron filings to hydrogen peroxide.


                Richard Barrans Jr., Ph.D.
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