Name ______________________________ Class ___________________ Date __________________
Skills Worksheet
REAL WORLD APPLICATION
Cross-Disciplinary
What Is Your Favorite Flavor?
Read the following paragraphs, and complete the exercises below.
The word chromatography, which describes a process for separating parts of a
mixture, comes from the Greek words for “color writing.” Chromatography was
originally used to separate colored plant pigments. Today, many industries use
chromatography to separate mixtures.
HOW CHROMATOGRAPHY SAVES MONEY
Thanks to chromatography, foods with a greater variety of flavors are now
available at a lower cost. In the past, all foods were flavored with natural
compounds derived from plants. However, this process is often expensive, and
supplies of the necessary plants are limited. Today, many of the chemical
compounds that make up these flavorings are produced in the laboratory.
TESTING COMPLEX FLAVORINGS AND FRAGRANCES IN THE LAB
Some flavorings, such as the compound benzaldehyde—which is the flavoring of
wild cherry—are fairly easy to make. However, creating flavorings that are made of
many compounds is much more difficult. More than 100 compounds are sometimes
found in a single flavoring! Researchers use gas chromatography to determine what
compounds are in some flavorings so that they can make these flavors in the lab.
The same process is used to create artificial fragrances. In many cases, the
synthetic compound is identical to the natural one, but it is much more affordable.
For example, any fragrance that smells like roses contains beta-phenylethyl
alcohol. It costs thousands of dollars per kilogram to extract this compound from
rose oil, but it can be made in a laboratory for just 1 percent of this cost.
EXERCISES
1. What is chromatography?
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2. Explain how gas chromatography helps scientists create complex flavors and
fragrances in the laboratory.
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3. What are two advantages of using synthetic compounds rather than natural
ones for certain flavors and fragrances?
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Original content Copyright © by Holt, Rinehart and Winston. Additions and changes to the original content are the responsibility of the instructor.
Holt Science Spectrum
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Solutions