Combined effects of chilling rate, low voltage electrical stimulation and freezing on sensory properties of bovine M-longissimus dorsi

The single and combined effects of low voltage electrical stimulation (LVES ), chilling rate after slaughter, and freezing/thawing during ageing on the tenderness of bovine M. longissimus dorsi were studied. Of 27 young bulls, 14 were exposed to LVES (90 V, 32 s, 15 Hz) immediately after stunning. Fo ur different treatments regarding chilling rate and freezing/thawing were r andomly assigned to each of the 27 young bulls. Samples were aged for 7 day s at 4 degrees C and analyzed after freezing and thawing. The experimental design allowed direct comparison of different treatment effects and an asse ssment whether these were additive or not. As expected chilling rate after slaughter had highly significant effects on final tenderness, based on resu lts from a trained sensory panel and Warner Bratzler (WB) shear press analy sis. The effect of LVES on final tenderness was not statistically significa nt. The introduction of a freezing/thawing step during ageing did not signi ficantly affect tenderness. The effects of individual treatments depended o n the tenderness level and were relatively larger at high WE shear press va lues (7-8 kg/cm(2)) than at low values (4-5 kg/cm(2)). The results indicate that the treatment effects were not additive, but that the treatments are alternatives to tenderize beef. (C) 1999 Elsevier Science Ltd. All rights r eserved.