For best results from homegrown popcorn the moisture should be adjusted prior to popping. This blog details the procedures I use to achieve great popping results.
When I originally started working with popcorn I was disappointed with how poorly it popped. After doing research I realized that I needed to adjust the moisture for best popping ability. Either too little or too much water in the kernel can lead to poor popping. The difference is demonstrated by the photo of popped corn. One batch of popcorn contained 10% moisture and the other batch contained 14% moisture. The final volume was about twice as much in the batch with the proper moisture, and there were fewer old-maids.
To test the percentage of moisture in a batch of popcorn I use the following procedure:
Grind some popcorn
Weigh out a sample
Dry in Oven at 250 degrees Fahrenheit for 3 hours
I use a sample size of about 20 grams because that fits the capacity of my scale, and allows me to use stainless steel condiment dishes. I have also used tuna cans or pieces of aluminum foil.
I calculate the moisture content of the bulk corn using this formula:
(Original Sample Weight) – (Dried Weight)
---------------------------------------------------------- = Percent Moisture in Bulk Corn
Original Sample Weight
A few years ago I ran a series of popping tests to determine the optimal moisture content. I made this graph which shows the final volume of popcorn compared to the percentage of moisture in each batch. I have settled on 13.5% moisture as my target. That provides a good balance between great popping ability, high quality, and good long-term storage. Too much moisture in popcorn can lead to mold.
The formula I use to figuring out how much water to add is:
Water to Add = (Weight of Bulk Seed * (1-%moisture in bulk popcorn) / (1-Target % moisture)) – Weight of Bulk Seed
Sorry if your eyes just glazed over, mine sure did when writing that. No worries, here is a real world example: the most recent that I moisturized. I had a batch of popcorn seed weighing 3000 grams. It contained 8.7% moisture. I wanted to adjust the moisture to 13.5%.
Water to add = 3000 g * (1-0.087)/(1-0.135) – 3000 = 166 grams.
Here is a photo showing what it looked like in the real world. That sure seems like a lot of water to me, but I do live in a very arid climate!!! After adding the water, I shake the bottle occasionally so that the moisture gets evenly distributed. I wait 2 days after adding water before popping the corn. Once the moisture has been measured and/or adjusted I store the popcorn in airtight containers.
I have explained the scientific method for adjusting the moisture in popcorn. It could also be done by intuition and experience: For example, storing the corn open to the air for about a week at room temperature and 70% humidity. Another example would be to arbitrarily add small amounts of water and test pop batches until it pops great. These methods are available to anyone who grows popcorn at home. This is part of the reason why I believe that landrace gardening is a path towards food security through common sense and traditional methods.
I’m feeling a bit under the weather this week, so I’m postponing the decision about a topic for next week’s post. I welcome feedback about topics that you’d like me to cover.
Joseph Lofthouse grows vegetables in a cold mountain valley where he practices the art of landrace gardening in order to feed his community more effectively.