I have been tinkering with this important experiment for few weeks now. I need a set of corn samples with varying protein content.
The first problem I had was easy. Corn samples with varying moisture content. I bought some cracked corn from my favorite feed supply store. Sifted it to remove fine powders caused by milling. Soaked in generous amount of water for two hours. Drained for 30 minutes. Scattered the wetted corn evenly on trays, about one cm thick. Set the electric fan in front of it for air drying. Got measured amount every hour for ten hours. That’s it I had ten corn samples with varying amount of moisture. It was 11 in all including the control sample. I stored them in chiller for two days to let the moisture equilibrate.
It was easy but it took me several trials before arriving to a satisfactory results. Keeping the corn in humid area will encourage moisture gain, but, it took too long and the molds were already grown before getting acceptable moisture. Rapid oven drying of wetted samples caused gelatinization of starch. Gelatinized corn is useless for our setup. I found out later that air blow drying gives excellent outcome and could be way faster than oven.
Then, as I said. I need another set of corn samples with varying protein content. For the start it should have 30 % moisture content. Add 4-6 grams urea per 100 grams corn. Ferment for two weeks at 30 to 40 ⁰C. Expect protein content gain after two weeks. That is if the spoilage organisms such as mold won’t penetrate the measures I set.
Urease producing bacteria is necessary for successful fermentation. It is found almost everywhere including the urea and corn samples I have. Heating is good for destroying spoilage organisms but might as well kill the needed microbes. Hermetically sealing the mixture is a nice solution. It’s gonna keep beneficial bacteria alive while keeping aerobes away and those that already in dormant.
The protein enrichment experiment has been going for four days now with no sign of molds, bacterial growth and discoloration. I am hoping it last until the target period.
My job description has going out of line lately. However, my stored knowledge on food processing often come in handy.