More than 30 stores have been rebranded as The Co-operative Food, and a further 170 are scheduled to be made-over by 2010.
Somerfield stores yet to be converted carry a wide range of Co-operative-branded grocery products, and a full range of festive groceries are due to be rolled out this week.
Consumer websites have also been integrated and pos material created to explain the changes to shoppers.
Meanwhile, the society is consolidating its supply chain. Consultations are under way with staff at Somerfield's distribution centre in Huntingdon where up to 80 jobs could be lost.