Science Saturday: Spicy Spicy Science

So, I like hot food. I like science. Why not combine them together? I was listening to Tom Allen on CBC Radio 2 Shift today (apparently, he provides me with much insight) discuss the Scoville Unit and determining the heat of peppers. Then I got to thinking about converting it into a science lab. Here we go:


So, Wilbur Scoville designed this scale in 1912 to determine and compare the pungency of peppers. This is defined by the amount of capsaicin contained within the pepper. His test, known as the Scoville Organoleptic Test, involves soaking dried peppers in alcohol (capsaicin is alcohol-soluble) and determining by how much it must be diluted with sugar water until it is undetectable to taste. So a pepper with a rating of 2000 Scoville Units must be diluted over 2000 times (its original volume) to render it unpercetable by human taste.

How does this apply to the science classroom? Well, this makes a fantastic open ended science lab that can cover important topics such as: experimental error, subjectivity of methodology, issues with perception, observation and experimental design.

My idea is to provide students with the background information presented above. Have them design an appropriate experiment to determine the Scoville Rating of an unknown sample. Provide each student group with a different sample (I would recommend nothing too hot as it can burn eyes and mucous membranes) and let them run their experiment. Students should have the opportunity to present and discuss the different methodologies chosen by their peers.

Of course, the one outstanding question on your mind is: you want me to have students drink alcohol? Well, it is unfortunate that capsaicin is not water soluble, but it is fat and oil soluble so I would recommend using vegetable/olive oil instead of alcohol in class.

Finally, here is how Scoville did it. He had a minimum of five tasters who were allowed to taste only once per session to prevent prior tastings from influencing their decisions. Because of the subjectivity of the testing, today we test through liquid chromatography.


One more extension is to discuss why drinking water after eating food spiced with capsaicin doesn't work (it is not water soluble). Whereas the drink of choice, beer, has a mild amount of alcohol which can alleviate the burning sensation. The alternative drink, milk, has a compound casein (which is lipophilic or fat-loving) that surrounds the fatty capsaicin molecules and washes them away.

This is a easy to run lab which should provide ample opportunities for students to explore the scientific method while having a bit (or heaps) of fun.

More information on Scoville, capsaicin and peppers:
Wikipedia
Chile Pepper Scoville Scale
The chemistry of capiscum

On the pedagogy of making pancakes

In my home, we've recently begun experimenting with making our own pancakes from scratch. The first thing we realized is just how easy it is to prepare excellent tasting, nutrious pancakes from scratch. We felt almost deceived by the pancake mix companies (you know who you are) for tricking us into thinking we needed pancake mix. Then we realized that we had allowed that to happen.

The interesting thing about making pancakes is how it mixes both science and art. You can easily get a recipe from the Internet to make pancakes of any description. The quantities of ingredients needed and the order to mix them is easy to follow. However, I have learned that the art of cooking the pancake is not so easily described.

I find myself sometimes watching the pancakes closely as they cook in the pan. On these occasions I tend to flip them before they are ready and they just don't look nice once they are done. On other occasions, I become distracted, either intrinsically or extrinsically, and forget to flip the pancakes and they burn. However, on those rare occasions the right mix of attention and distraction occurs and I flip the pancake at the perfect moment and it looks, well, good enough to eat.

I've tried to scientifically determine when the pancake should be flipped. The recipes say to wait until the bubbles have formed deep in the middle. However for my combination of cheap stove and cast iron pan, that causes them to burn. Some days I need to flip before bubbles form and other days I need to wait to flip. There appears to be no consistent pattern regarding the flipping of the pancake. It seems to be determined by the state of the mix, the pan and the stove on that particular day.

Sure things may work better if I had a stove that actually distributed heat properly. Or maybe if I chose to use a Teflon pan. But regarding the stove, I work with what I have. Regarding the cast iron pan, it may be archaic, it may be more work, but it makes everything taste so much better.

To spice up the pancakes, we experiment with adding fruit to the mix. Pineapples, apples, bananas, and strawberries have all made it into the mix at some point. These small additions help keep things fresh.

Now, when we first started we went on a pancake bonanza and ate them everyday for a week. That resulted in the avoidance of pancakes for the next week. Now we try to balance pancakes with other meals like a nice hearty oatmeal or some greasy French toast.

I know that every time I make pancakes I do it better, faster and easier. I am better able to predict when to flip the pancakes to have them turn out perfectly. I still screw up here and there and burn one or under cook some, but I take those mistakes in stride, learn from them and move forward.

Just some food for thought ... (sorry, its late couldn't resist the horrible pun)