The Science in Corn Parching: Some Things You Should Know

When we were growing up, parched corn was a popular snack not just because of the availability of corn (field corn), but because It was a powerful bonding tool at home and at school. Those who went to boarding school can attest to its hunger quenching properties and how rumbling stomachs were silenced. Those who went to day schools can tell you the number of stories that were told, friendships that were cemented, and distances that were covered on foot thanks to the power of this parched grain. How to make the best parched corn became a tiny obsession of mine in my teens because I noticed grandma’s corn popped best and was the crunchiest.

 If you have tried parching corn using a regular pot and without basic tips, you would realise that the results wouldn't look like your grandmother's (for those whose big mamis master(ed) the art) or the roadside vendor's. Parched corn lovers who have tried to do this themselves at home have probably wondered why they don't get good results.

For those who asked for help like I did, you were certainly told to make sure that the fire is hot, add a little oil, add a little water or to do all three. These tips don’t change much, especially if you don't know the ‘whys’ and ‘hows’ surrounding them. It takes more than these to make the corn pop and to make the grains pop and tooth-friendly. Here is a little physics to help you. 

Science says that corn pops because of the moisture found inside the grain. These grains contain water, oil and starch. I guess you now know why you were told to add a little oil or water while parching corn. There are people who go as far as soaking the corn for about 30 minutes or so and then drying it again before it is parched. When heat is applied to corn, the moisture inside gets hot and tries to expand. In the process, the starch is gelatinized and the hot oil and water (steam) due to pressure forces itself out through the seed coat. The grain becomes crunchy as a result of this. The grains that are turned inside out by pressure when they crack are those that pop well.

It is possible to achieve the results as seen in the picture using regular fufu corn (field corn), not the yellow species of corn used by Hausas (probably a wild or hybrid strain of popcorn) without adding water or oil. This is because even if the moisture content is okay and the heat is low, the corn won't pop and it will be hard. If the heat is too high, on the other hand, it won't pop well since the moisture hasn't had enough time to make the grain expand.

A special pan shaped like a frying pan is used in some places in the North West Region of Cameroon. It’s possible that they are used elsewhere but I’ve seen them nowhere else. This pan is usually made using corrugated zinc or an aluminum jerry can. The can is cut open and the cut part is completely removed. A wooden handle is then attached to it. The advantage with this pan is that it's a good conductor; it can easily transfer heat either by gaining or losing it. This makes it easy to regulate heat.

However, you shouldn't expect a miracle because field corn isn't popcorn. A good portion, probably one third, of the corn would expand but not crack open like popcorn if you apply these tips. That’s what makes it parched corn, anyway.


M. Norwanghe