Lozano struck in the 35th minute of the Group F game as a disjointed Germany were caught out on the break, Javier Hernandez skilfully setting up his teammate to compose himself and fire home.
"We are very happy," Lozano told reporters. "My teammates and I did some great work, we all ran our hearts out and this is the result of all this hard work.
"I don't know if it the biggest victory in [Mexican] history but one of the biggest for sure. It is great to start on the right foot when you are playing against the world champions.
"I would have to agree it is the best goal I have scored in my life. We all dream of playing in the World Cup."
The result means that Mexico have won their opening match at a World Cup for the fifth time in their past six tournaments.