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    Outreach and Education Division

    The EDUCATION AND OUTREACH DIVISION supports chemistry education at all levels, including K-12, college, and adult/continuing education. It maintains liaisons to the Chicago Public Schools and the American Association of Chemistry Teachers (AACT). The Division engages the general public in chemistry-related educational activities, participates in ACS activities at the annual Illinois State Fair, and publicizes all events and news-related content. The division oversees the annual Project SEED program for the Section as well as the Project SEED scholarships. The Division also assists public officials and other community bodies concerning chemistry-related matters. The Education and Outreach Division includes the Education, Outreach, Project SEED, and Public Affairs Committees.

    The EDUCATION COMMITTEE provides chemistry-related educational programs and information to learners of all ages and actively engages with educators at the pre-K-12 and college levels. Subcommittees include:

    • AACT Liaison
    • College Education Subcommittee
    • Continuing Education Subcommittee
    • Chicago School Board Liaison
    • K - 12 Education Subcommittee

     

    The PUBLIC AFFAIRS COMMITTEE ensures that section members and public officials and bodies are informed of matters where the knowledge and practice of chemistry is of substantial public importance. These matters can include government issues, environmental issues and the social responsibility of chemists. The Public Affairs Committee gives the Public Affairs Award biennially.

    The OUTREACH COMMITTEE engages the general public, educators and children in chemistry-related educational activities and participates in many different types of events around the greater Chicago area.   Subcommittees include:

    • Community Activities Subcommittee
    • Illinois State Fair Subcommittee

     

    PROJECT SEED COMMITTEE identifies interested low-income and/or minority high school junior and senior students who are interested in participating in a paid summer research experience with  a college or university faculty member.  It supports financial and logistical concerns for the student/ faculty relationships and communicating  relevant program information to the national ACS organization.  The committee is also responsible for distributing Project SEED awards to support the internships. 

    Peachy Keen

    Kids, did you ever think of freezing a whole peach or even one cut up into pieces?  Why not?  If you tried it, you'd find that all of the flavor was gone and that the perfectly peachy texture became mush upon thawing. So what can be done to save peaches beyond their growing season? 

    Please note:  All chemicals and experiments can entail an element of risk, and no experiments should be performed without proper adult supervision.

    First, let's demonstrate why simply freezing a peeled and diced peach is a bad idea. Fill a plastic zip-top bag with water and seal shut. Have an adult partner find a pointy object such as a knitting needle. Imagine that the bag filled with water is a pulp cell inside the peach. Imagine that the needle is an ice crystal. Holding the bag over a sink, have your adult partner puncture the bag several times making holes for the water to leak out. This is what happens when ice crystals puncture pulp cells during the freezing process.

    What scientific trick can be used to prevent this? The substance that we call sugar is actually sucrose, a disaccharide, or double sugar. Sucrose is famous for being hygroscopic, meaning that it loves to grab hold of water at the molecular level. By adding some sucrose to diced peaches, some of the water is pulled out of the peaches and creates a syrup with the sucrose. The trick is that when the syrup freezes, the sucrose holds onto some of the water, and that prevents the ice crystals from getting so big that they poke holes in all the cells, which makes all of the moisture leak out when the peaches thaw.

    For one pound of diced peaches which you would like to freeze, add about ½ cup of sugar. Before doing that, however, be aware that neither sucrose nor freezing temperatures will stop peaches from turning brown. For that, more science is needed, in the form of an acid. Since browning is really an oxidative process, what's needed is an antioxidant. Ascorbic acid, which is good old vitamin C, works well for this. About 500 milligrams (mg) will do. Crush up a vitamin C tablet between two spoons, dissolve it in 3 tablespoons of water, and mix into the peaches before the sugar.

    Once the peaches, vitamin C, and sucrose are mixed, let the mixture sit for 15 minutes until a thick syrup forms. Transfer the peach mixture to zip-top freezer bags for long-term storage. Enjoy your kitchen chemistry all winter long! 

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    Kathleen Carrado Gregar, PhD, Argonne National Labs 
    [email protected]
    December 2009

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    References:  Alton Brown of the "Good Eats" TV show on The Food Network: http://www.goodeatsfanpage.com/Season10/peaches/peachy_keen_tran.htm