Store bought cakes will last longer if stored with 1/2 of an apple.
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Keeping Cakes Good for Eating. A few years ago, a dear pal baked us a cake. It was a very, very moist cake... She didn't say how long it would keep for or if I should freeze it or refrigerate it. . .
To keep cakes fresh, especially pound cakes, place a slice of apple beside the cake inside the container. The cake will actually become more moist.
