Wow, red epidermis?

[frogsleap farm]

I've only been at this (tomato breeding) seriously for 3 years. Each year I learn something new and keep an eye out for the unexpected. Here's a new one for me - an apparently red epidermis on a yellow tomato. This fruit is from one of four F3 plants. The F2 parent had the same trait. I made a couple of crosses to a striped F3 sister line, so can track inheritance. It a very tasty large cherry, w/ BTD as a parent in the F1.