Murr told News Corp Australia that she was upset by the comment and confronted Meeuwissen about it the following day, telling him it was unacceptable.
"Josh definitely crossed the line with that comment," Murr said. "He didn't use very good judgment.
"We all know that Josh is a bit of a shit-stirrer and likes to get reactions out of people by saying things he probably shouldn't.
"But that comment was taking it too far. To have him say that was quite upsetting."
In March, Meeuwissen told KISS FM's Kyle & Jackie O that he was a victim of "selective editing" on My Kitchen Rules and that producers told him what to say to camera.
Meeuwissen addressed the "slut" comment directed at Amy saying "I totally understand I didn't use my best judgment, it's in the past now.
"Amy and I are still friends. I was shocked that they [My Kitchen Rules' producers] said they were going to show that comment."
Murr said she gave Meeuwissen a serve about his behaviour the day after filming the ultimate instant restaurant episode.
"At the time I was focusing on the rest of the cook," Murr said. "I put it at the back of my mind and focused on what I had to do that night but I did speak to him the next day.
"I didn't feel that addressing the comment at the table in front of the other judges and contestants with 1.5 million people was the right thing to do.
"I wanted to talk to him as an adult. Josh knows that when he said that he didn't make me feel good.
"He now understands very clearly that it is never appropriate or funny to say that to someone. He apologised. He was very sincere in his apology. I accepted that apology."
Josh also addressed criticism of his behaviour towards wife Amy during filming of Seven's reality cooking show.
"I'll be the first to admit I wasn't on my best behaviour during filming," Josh told Kyle & Jackie O.
"I can't deny that we didn't argue. But every moment we've been loving and respectful [has been edited out]."
The show airs on TVNZ 2 in New Zealand.