England Under-21 international Nketiah converted at close range in the 88th minute in California to give the Gunners a 2-1 victory over the German champions.
Nketiah, 20, also impressed in the recent 3-0 friendly defeat of Colorado Rapids and could be set to add to his eight Premier League appearances, all of which have come as a substitute.
"We have a responsibility with young players to give them chances," Emery told reporters.
"We want to use different young players to help.
"Some players will be with us in pre-season; some players will be with us in the season. Each minute they show their performance against big players. For example, the [duel] Nketiah [won] against [Niklas] Sule.
"Today was very positive. Against Colorado Rapids a lot of young players played. We need them for the moment but also in the future.
"Our responsibility in this club for the history, present and future is to give young players a chance."
Homegrown prospects could prove especially useful amid doubts over Arsenal's spending power, with teenager Gabriel Martinelli the only addition of the close season to date.
Freddie Ljungberg's recent promotion from Under-23 head coach to first-team assistant should expedite the emergence of these youngsters and Emery praised the Swede's "very positive" start to his new role.
"With Freddie we are working," the former Sevilla boss revealed.
"Above all he's helping us with the young players because he knows every young player better than us."
Ljungberg spent all of last season working with the U23 side, and will be replaced by another former member of the Arsenal first team in Steve Bould.
The news of the Swede’s promotion was broken back in June and came into effect from July 1st after he won 12 from 26 matches in his former role.