NAME______________________
                                          Lab: Testing for Food Additives
                                                      DATA SHEET

     Name of Fruit                                   Starch/Iodine Test                                  Sulfur Dioxide
                                            Amount of Iodine    Amount of Time Purple            Present (Yes/No)
                                                    Added                 Color Persisted

     ________________            ______________          ______________                       __________

     ________________            ______________          ______________                       __________

QUESTIONS

1. Why might food such as fruit require more additives and preservatives than food such as cereals?


2. a) How is sulfur dioxide added to fruit?

   b) How does sulfur dioxide stop browning in the fruit?

3. a) What is senescence?

   b) How does senescence change the texture of a fruit?

4. (T or F) A bruise on an apple is an example of enzymatic browning.

5. (T or F) Enzymatic browning is not affected when fruit is placed in a vacuum.

6. Why does iodine lose its dark color in the presence of sulfur dioxide?

7. Which of the following rooms would be most practical, both for costs and safety, for the
      long-term storage of fruit?
         a) atmosphere = 99% carbon dioxide, 1% oxygen;
         b) atmosphere = 95% nitrogen, 5% oxygen;
         c) atmosphere = no air / is a vacuum;
         d) atmosphere = 50% oxygen, 50% carbon dioxide.
    Explain your choice.