I've discovered a difference in color in my engine oil. Is it possible my antifreeze has leaked into my engine block?

Hi,
When posting, please give more details. To be able to answer that, I'll need to know what engine, and what the difference in color is. When you changed your oil did you have some burnt up antifreeze /yellowish nasty stuff at the bottom of the oil drain pan? If so, than this is true.

Pete