Food shoppers and investors looking at the packaged food aisles of big grocery stores have reached the same conclusion: There is nothing to buy.
The classic consumer food companies—makers of cereals, snacks, soups and condiments—are no longer the staples of pantries or portfolios. Shares of some are down by a third or more over the past year as strategies to boost sales fail, and consumers embrace fresh food and new brands.
Supermarkets...