Lipid content and oxidation in soy protein and ground beef mixture

The effects of varying proportions of textured soy protein (mixed with ground beef) on the evaporative loss, cooking yield, lipid content, lipid oxidation and overall acceptability were studied in cooked patties containing 0 to 40% soy protein. All analyses were made of patties cooked immediately after thawing. Lipid oxidation determinations were made after 48 and 72 hours of refrigeration. The results showed that when compared to all beef patties the cooking yield was significantly higher for those containing 30 and 40% soy, and the evaporative loss was lower for the patties containing 40% soy. Total lipid content was significantly less in all samples containing soy protein. Compared to 100 percent ground beef, there was less fat oxidation in samples containing 30% soy which were refrigerated 48 and 72 hours, and in samples containing 40% soy refrigerated 48 hours. Overall acceptability was lower for all soy/beef patties as compared to those made of 100 percent beef