Joachim Low's side led the hosts 5-0 at the break thanks to a brace from Toni Kroos and one goal apiece for Sami Khedira, Thomas Muller and Miroslav Klose, who broke Ronaldo's all-time tournament goalscoring record with his strike.
Andre Schurrle went on to add two more after the interval, with Oscar netting a consolation in a 7-1 scoreline, but Hummels has admitted that the Germans went easy on Brazil in the second period after pledging not to showboat or inflict more humiliation on the Selecao.
"We just made it clear that we had to stay focused and not try to humiliate them," he told reporters. "We said we had to stay serious and concentrate at half time. That's something you don't have to show on the pitch if you are playing.
"You have to show the opponent respect and it was very important that we did this and didn't try to show some magic or something like this. It was important we played our game for 90 minutes."
The result was Brazil's joint-heaviest World Cup defeat and the biggest semi-final loss in finals history.