Kosher Laws

What is the reason why meat and dairy products should not be mixed?

Back in Biblical times, if you want to eat, people wearing a wooden bowl usually related to their size. Bowls were not washed after a meal (no detergent or hot water), they were cleaned. If a person had dairy products for breakfast, the Bowl porous wood kept part of the culture of milk that could turn rancid in the hot midday sun. If the next meal for the person appearing to meat, mixing the two after getting off the hepatitis that has killed at that time. The people have finally realized that this was not the case if you had a separate bowl for dairy products and meat. It is now under kosher law.

I think that is something called cross-contamination, but I do not know

I think it has something to do with the Bible states that you can not eat beef boiled in milk of mothers or something like that. I think some Jews interpret tit more strongly than others.