It should be fine. Try it out... see how they handle it. If it seems to upset the tummy... hold off for a little longer and try again in a month. If not, then you are good to go. I have been giving my son meats since about 8 months with no problems.
Wow... guess I really didn't read the answers above me.... extremely rude. I completely understood your question..... hamburgers...lol. I guess you have to write your questions fool proof, such as ground burger from a cow....lol!
Anyway... hamburger isn't unhealthy... as babies diet begins to ween more and more off formula and breastmilk... they need to begin to eat other sources of nutrition. Red meats have many different nutrients that babies need. Most babies aren't ready for a steak, so hamburger is a good alternative. I make casseroles with ground hamburger and veggies all the time and give them to my son. He loves them, and it is healthy for him.
I think when most people think of hamburger, they think hamburgers and then think mcdonalds or something. Yes, if full grown adults eat hamburgers all the time, it probably isn't the best choice of a diet. But incorporating meats into a babies diet is excellent. You just need to make sure they are ready to digest them. Babies need meats and fats in their diet!
Ignore the rude answers.... they don't know what they are talking about.