Improved tenderness of restructured beef steaks by a microbial collagenase derived from Vibrio B-30

To reduce connective tissue toughness Vibrio B-30 collagenase was evaluated for its ability to degrade muscle collagen in a restructured beef (RSB) product. Dissected muscles pooled from clods of 4 USDA choice chucks were made into three RSB products: untrimmed control (C), hand trimmed of epimysium (T) and untrimmed and treated with 0.01% collagenase (E). RSB products were held for 24 hr at either 2 degrees C or 11 degrees C and were analyzed either raw or after heating (40 degrees C for 1 hr). Aerobic microbial load remained low (1-2X10(2) cfu/g) during the 24 hr 11 degrees C incubation. Heated samples of enzyme treated RSB had lower Lee-Kramer shear values than controls. In both raw and heated samples enzyme treatment increased hydroxyproline solubility. An enzyme treatment of 24 hr at 11 degrees C followed by heating produced maximum tenderization. Although optimum treatment conditions need to be defined by further research, Vibrio B-30 collagenase appeared to be efficacious for the tenderization of RSB products.