The food company launched the review last month, following the sale of the business in March by Premier Foods to Exponent Private Equity and Intermediate Capital Group.
Carat and Starcom MediaVest Group, which was the incumbent on the business, pitched against Initiative. Starcom continues to handle media for the remaining Premier Foods brands.
Quorn is set to launch marketing activity in a bid to strengthen the appeal of the brand to weight-conscious customers, as well as increase frequency of purchase with the brand's existing vegetarian consumer base.
Kevin Brennan, chief executive of Quorn Foods, said: "We are excited about working with Initiative, who were not only forensic in their analysis of how to maximise our TV investment, but also showed a real understanding of how this investment can impact and drive our sales."