Bonucci was criticised by a number of players for saying that the blame for the incident was split "50-50" between the 19-year-old player and the Cagliari fans.
"I was interviewed right at the end of the game, and my words have been clearly misunderstood, probably because I was too hasty in the way I expressed my thoughts," he said on Instagram.
"Hours and years wouldn't be enough to talk about this topic. I firmly condemn all forms of racism and discrimination. The abuses are not acceptable at all and this must not be misunderstood."
Kean, who had been jeered throughout the game, stood in front of the Cagliari fans behind the goal and opened his arms after scoring Juve's second goal in a 2-0 win.
In response, Cagliari’s supporters made the noise which is described in Italy as “buu” and is regarded as a racist insult, although some fans argue it is simply to annoy opposing players regardless of race.
Bonucci said at the time Kean should have celebrated with his team mates -- a remark which prompted England forward Raheem Sterling to comment: "All you can do now is laugh."
