What is gross contamination?

Answer 1

You want to make a chicken stir fry. You'll cook the chicken first, so why not chop it first? You chop it, rinse off the knife, and chop your vegetables on the same cutting board. This gets chicken germs on the vegetables, and if you don't cook those thoroughly, you might get sick. Another instance of it is in agriculture; remember the e. coli in the spinach a couple years ago? That was caused by the waste from a cattle farm running into the spinach crops. What we have going on currently is salmonella on inherently safe vegetables; that could be another spinach situation, or it could have been a picker who did not wash his hands after going to the bathroom (or making a chicken stir fry).