When I write about inflation, I sometimes hear from readers who say the published price indexes don't reflect what they're experiencing at the supermarket. And they're right: For the last year and a half, food-price inflation has far outpaced the regular Consumer Price Index.

How long will this trend continue? Food companies should have a better idea than most of us, and their projections don't provide a consistent answer. For example, Ralcorp Holdings and Panera Bread both reported their earnings Tuesday, and both talked to analysts about food cost trends.

Ralcorp, which makes private-label cereal, crackers, peanut butter and other grocery items, thinks this year will be about as bad as last year, when the CPI-Food rose 10.4 percent. Here's what Chief Executive Kevin Hunt said in a conference call this morning:

We expect inflation of cost of goods sold to be 10% to 12% during fiscal year 2012 and will consist of increases in raw materials, packaging and freight. The primary drivers are consistent with last year's being durum wheat, cashews and tree nuts particularly almonds and pecans and peanuts. Excluding durum wheat and snack nuts, this increase would be 5% to 6%.

Panera, the bakery-cafe chain, also uses a lot of wheat, albeit a different grade than durum, which Ralcorp uses to make pasta. But Jeffrey Kip, Panera's chief financial officer, sees a more benign inflation outlook, he told analysts today:

... a lot of items have come down materially from what we thought even six months ago and we're going to end up getting leverage in that line. We think our all-in inflation is going to be around 2.75% in 2012.

Of course, Kip and Hunt could both be right, since their companies buy different mixes of food commodities. Consumers can only hope that their shopping baskets look more like Panera's than like Ralcorp's.