8.30.2010

starting new

The first day of school. New notebooks, pens, and textbooks. New classes, teachers and friends. Something about the beginning of a new school year brings out a fresh attitude in everyone. Its before anyone feels overwhelmed with projects and papers. Students and teachers start out with new goals and ambitions that might never be. But that first week of school, the smell of new school supplies and clean classrooms is nostalgic. It makes you feel that you could start over, make new friends, be a new person.

I have always loved school, especially the early fall when you walk in to school feeling ready for another year. I think that feeling is part of why I want to be a teacher. Seeing kids excited about learning is most prevalent in the first weeks of school and I want to be a teacher who keeps kids enthusiastic about learning all year long. I love coming home from a day of school and feeling like I have learned something.

Along with my goals for the new year I decided to start writing things that I learn in this blog. Then at the end of the year I can look back at all of the things that I have learned.


The First Lesson:
Decaff or Regular?



I have always wondered how they make decaff coffee. Isn't that the whole point of coffee, to wake you up in the morning? Today in Chemistry we looked at chapter 1 and the process of decaffeinating coffee. All cocoa beans have caffeine and theobromine in them naturally, so how do you remove the caffeine and maintain the flavor?

Well it used to be that they would carbon tetrachloride to soak the beans and then a long decanting process to extract the caffeine and theobromine but after years of this process they discovered that this chemical was doing more harm than good. In the 1980's there was a solvent scare and many of the chemicals that were frequently used for this process were deemed unsafe for human consumption. After years of trying different methods the coffee industry (more like chemistry industry) finally developed a method that we still use today.

By using carbon dioxide in its supercritical form (in between a gas and liquid) and raising the pressure you are able to bring a supercritical fluid out of the coffee beans. The pressure is then released and the CO2 evaporates off of the beans. As it evaporates, it is filtered through charcoal and this filtering process removes all of the caffeine and theobromine that gives your coffee its kick.

Regular coffee contains about 106-164 mg of caffeine per serving while decaff contains 2-5. So by drinking decaff you are getting a very small amount of caffeine in your drink and since we have changed the extraction process you really aren't losing any of the flavor.