What's behind the sudden shock of food inflation -- one of the economic sparks of the Egyptian revolution? Historically rough weather from Russia to Africa have hurt wheat and corn supply, while demand has zoomed forward as the world economy recovers and China and India eat more meat. Kay McDonald explains the wide ripple effect of higher corn prices:

Wheat and soy prices increase when corn prices are high, since their acreage allotment is replaced by corn. In addition, wheat and soy get substituted for corn as animal feed. 

High corn prices cause higher meat, dairy, wheat and soy prices for consumers. Since last June, the corn price has doubled. Soy and wheat prices are each up 60 percent. Cattle and hog prices have risen 25 percent.

And because of increased demand for a dwindling amount of oil which costs more to produce, embedded energy costs in food are another huge driver of today's higher food prices.

Read the full story at New York Times.