Characteristics of beef patties with low-salt (0.5%) and low-fat (<10%) contents were studied during frozen storage as affected by addition of Wakame seaweed (3%) and partial or total replacement of pork backfat with olive oil-in-water emulsion. Patties with Wakame presented less (P < 0.05) thawing and cooking losses and were softer (P < 0.05) than patties without seaweed. A softening effect (P < 0.05) induced by olive oil emulsion was observed only in seaweed-free patties. Lipid oxidation and microbiological counts in reformulated products were not a limiting factor for frozen stability. Wakame incorporation increased (P < 0.05) mineral contents, but all products presented the same Na/K ratio. Observed changes in microstructure were associated with seaweed addition (formation of alginate chains). All products were judged acceptable by the sensory panel. In the course of frozen storage no important changes were found in the target properties due to the different treatments. (C) 2010 Elsevier Ltd. All rights reserved.