I have actually tried to paint apples in a baggie before, but never with success. I think tonights is a good-enough-to-post painting. I had to paint the apples as if they were just sitting there in open air. Then once all the color is down, I started to put down the white lines (highlights). The painting still did not look that great so I used a half inch brush and started to knock back some of the apple and bag to get some better edges and hopefully the appearance of looking through plastic.