Zalon - who was signed to Winehouse's Lioness Records - recorded 'You Let Me Breathe' immediately after being told that the singer had died last year, and has decided to release the track in aid of the Amy Winehouse Foundation.
Zalon - who toured extensively with Winehouse - said: "It was my immediate response. It poured out of me. I was returning from Spain when I heard about her passing. I went to my producer JPL's house, and we wrote and recorded the song the next day. It was my way of dealing with it.
"The lyrics were about how helpless I felt, I could only cry for Amy, but that wouldn't bring her back. I was crying in the booth while recording, and I wasn't strong enough to release it until now."
[Amy Winehouse performing at the Brit Awards in 2007]
Zalon also paid tribute to Winehouse's family for setting up the Amy Winehouse Foundation - which aims to support charitable activities that provide help and support for young people who are suffering from addiction, ill health or disability.
He first met the star when she stormed the stage when he was performing at a London club to tell him how much she loved his voice.
"I'm so grateful to her, and her family are doing fantastic work with the Foundation", Zalon added. "It is only right to donate the proceeds of the single to the charity. It's an amazing cause in the name of an amazing person. She would be so proud of it."
'You Let Me Breathe' is out now.
Photo gallery - Amy Winehouse 1982-2011:
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