Research finds key to delay lamb discolouration

... so diet and stress prior to slaughter, as well as abattoir and processing factors. "When the antioxidant vitamin E is included as a dietary supplement to lambs prior to slaughter, the increased concentrations of muscle vitamin E are instrumental in ...

http://www.abc.net.au/news/2013-12-05/new-insight-into-lamb-meat-colouring/5138526