The Saints were beaten 20-11 in France on Saturday as their Pool 5 campaign got off to a losing start.
Despite seeing his side come away without any points, Mallinder believes that they put in a good performance.
"It's really disappointing because we were within seven points all game, so losing the bonus point at the last minute is a blow," he is quoted as saying by Sky Sports News. "But I can't criticise the efforts of my players or their ambitions in trying to win the game.
"Racing are a very good team as we know, they are very physical, strong and probably different from most of the teams we will face in the Premiership."
Northampton continue their European campaign next Saturday when they host Ospreys.