The position became available after Pierpaolo Petrassi MW moved to Waitrose as its BWS manager, replacing Justin Howard-Sneyd MW, who is now global wine director at Direct Wines.
Jewell joined Spar last May as wine trading controller, tasked with overhauling its entire range.
As a result, own-label sales grew by 56% in November last year alone, compared with the same month in 2008.
She also launched the retailer’s first wine festival in February as part of a drive to boost the supermarket’s wine credentials.
Jewell had previously spent three years as agency director of HWCG, following a stint in Sainsbury’s wine-buying team.