Sensory Characteristics, Shear Values and Cooking Properties of Ground Beef Patties Extended with Iron- and Zinc-Fortified Soy Isolate, Concentrate or Flour

Ground beef patties made from 100% beef or beef extended with 20% rehydrated soy isolate, concentrate, or flour, with or without iron and zinc fortification, were evaluated for sensory, shear and cooking properties. With the exception of patties formulated with soy isolate, soy-added patties were rated as more tender (P <0.05) than all-beef patties. Soy isolate imparted textural characteristics to patties that were more similar to those of all-beef patties than to those of soy concentrate or soy flour extended patties. Patties made with soy flour had the highest cooking yields. Also, patties extended with soy flour had lower incidences of rancid flavor, but higher incidences of soy flavor compared with all other beef-soy formulations. Iron and zinc fortification produced a higher frequency of rancid flavor when used with soy isolate and concentrate.