My grandma's rural church cookbook A Century of Family Favorites 1879-1979 is still our family's go-to baking resource. We return to certain recipes over and over (snickerdoodles, chocolate chip cookies, among others), but I also enjoy browsing to consider the possibilities. One of my favorite ingredients that has cropped up is "10¢ worth of walnuts." Back then, would a cook from that region have known what that meant, measurement-wise? It led me to think about some of the other recipe ingredients, and whether a reader would know what to use or if it would even be available in their region, state, or country. For example, would someone know about or be able to get a brand-specific cereal such as Wheaties? Grape Nuts? A product like Mapleine? What about country style corn flakes? Bits o' brickle chips?
The September 2019 Journal of Chemical Education article Educational Modules for Increasing Indigenous Australian Students' Involvement in Chemistry (available to JCE subscribers, or ACS or AACT members)* brings many "ingredients" unfamiliar to me. But that is part of the point. Its author Colin Scholes, from The University of Melbourne in Australia, begins with a discussion of the under-representation of Indigenous Australians in STEM fields. As one way of boosting interest in the sciences among these students, he offers "four educational modules ... that translate traditional Indigenous Australian practices with their associated chemistry explanations." The module experiments focus on the materials from these traditional practices—cycad seeds, tea tree leaves, dried ochre powder, and spinifex straws.
The modules were used with Indigenous and non-Indigenous secondary students. Although a main objective was to boost interest in Indigenous students, the modules are interesting and useful no matter one's background. The tea tree oil module rang a bell for me—I've seen tea tree oil shampoo at local stores and read a bit about its benefits, but hadn't considered its chemistry before. The experiment itself requires actual tea tree leaves (a plant native to eastern Australia), but the chemistry of the products could be discussed. The author offers possible alternatives if the Australian reagents are not available. Students collect resin from spinifex straws; if not available, he suggests resins from juniper, pine, and fir trees. Powdered ochre can be purchased from art suppliers.
Once the materials are sourced, the experiments themselves are simple and straightforward. For example, in the ochre module, which highlights the pigments and colors seen in Indigenous art, students mix the powders with water and add honey as a binder. They then change its color in different ways: grinding the powder and heating it, and adding charcoal and heating. Afterward, they paint with their results. Instructors discuss the inorganic chemistry associated with the colors and their changes.
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