If at any point the food value of the commodity drops below the fuel value, the market will move that commodity into the energy economy. (calcars.org)
If the food value of a commodity is less than its fuel value, the market will move it into the energy economy. (earthpolicy.org)
If you measure price in ounces or grams of gold, you would see Sine waves in value of commodities over natural cycles versus the ever increasing price in dollars or other currencies, as these currencies are perpetually debased, with varying times from increase in currency supply to the eventual effect on price in said currencies. (money.stackexchange.com)