I know "red apple" is a slang term for First Nations people perceived as acting "white" (along the same lines as the use of "banana", "coconut", etc., as slurs), but I don't think that's how Doug meant it; after all, his point seems to have been that "racism" isn't about "race". It came across to me as more a random word salad than anything else, similar to that time when he referred to young black men with "their hats on and their little funny signs". It certainly sounds racist and is also oddly specific, but I at least am unaware of any stereotype about black people (young men or otherwise) carrying little funny signs.