Relative influence of low-voltage electrical stimulation, chilling rate and ageing time on tenderness of M. longissimus dorsi of Norwegian cattle

Summary

The effects of gender, low-voltage electrical stimulation (LV-ES; 90 V, 15 Hz, 20 s), chilling rate and ageing time on the tenderness of hot-boned M. longissimus dorsi were studied on 47 Norwegian Cattle carcasses. There were 24 female cattle (14-96 months) and 23 bulls (15-24 months) in the sample set, of which 12 from each gender were exposed to electrical stimulation. One part of each loin was chilled at 15 degreesC for the first 24 h post mortem and thereafter aged at 4 degreesC for 6 more days. The other part of the loin was chilled directly to 4 degreesC and aged until 7 days post mortem. Ageing time was the most influential factor for Warner-Bratzler shear force, but chilling rate was also highly significant. Neither gender nor LV-ES had significant effects on tenderness in this study. The combination of electrical stimulation and rapid chilling did not improve tenderness as much as moderate chilling alone. This experiment showed that chilling rate during rigor and time of ageing were the two most important factors for the tenderness of beef M. longissimus dorsi.