ZenithOptimedia had handled the media for Campbell's and Premier Foods brands such as Ambrosia and Branston Pickle. Independent Central Focus worked with the agency on planning.
Walker handled media for Quorn, which became part of Premier's roster of brands last year when its owner Marlow Foods was acquired for £172m.
The decision to hold the review of the business followed Premier's buyout of the Campbell Soup Company for £460m in July.
This will be welcome pre-Christmas news for new Starcom UK chief executive Linda Smith and her team; recently appointed client managing directors Avril Gallagher and Stewart Easterbrook and UK trading director Chris Locke. The agency beat the incumbents and Aegis-owned Carat to take the account.
According to Nielsen Media Resarch, Premier spent £8.2m on media last year, with Campbell clocking up £6.9m.
This week it was announced that Premier Foods had agreed a £1.2bn takeover of rival RHM, the owner of brands including Mr Kipling, Lyons and Hovis. The deal will create the UK's largest food firm, worth an estimated £2.5bn.
Industry speculation suggests that after the RHM takeover, Premier will be looking to slim down its roster creative agencies.
Premier Foods currently uses DLKW for Ambrosia and Branston Pickle, and Clemmow Hornby Inge for Loyd Grossman, while Publicis handles Oxo.
RHM's Hovis brands use DDB London, while McCann Erickson works on Manor Bakeries brand Mr Kipling as well as Bisto, Sharwood's and Robertson's.
Universal McCann currently holds media planning and buying for RHM. The media account is currently unaffected by the acquisition.
Starcom is also in the running for the £14m EMI records account, along with incumbents Media ±±¾©Èü³µpk10 and Carat; the pitch will also include independent the7stars and MindShare.
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