Changes in Quality of All-Beef and Soy-Extended Patties as Influenced by Freezing Rate, Frozen Storage Temperature, and Storage Time

All-beef and soy-extended patties were frozen to - 18°C in either 24, 48, 72 or 96 hr and stored at -23, -18 or -7°C for 0, 6, 9, 12, 18 or 24 months prior to evaluating various quality factors. In evaluations made immediately post-freezing, freezing to - 18°C in 96 hr reduced beef flavor intensity and juiciness for both types of patties. Except for juiciness, storage at -7°C for just 6 months produced sizeable reductions in quality. Longer storage produced gradual, but continual deteriorations in quality, especially color, odor, flavor and TBA values. Inclusion of soy reduced many of the negative effects of storage on quality.