With plenty of cattle planned to be slaughtered when coming off grass over the coming months – a recent study conducted by Teagasc has examined the meat eating quality of bull beef that is finished off grass.
In research carried out by Aidan Moloney, Mark McGee and Edward O’ Riordan of Teagasc, it has revealed how carcass fat score is not related to the eating quality of bull beef.
In terms of the market specifications, some beef markets require bull carcasses to have a minimum carcass fat score of 2+ ( or 6.0 on a 15-point scale).
In a lot of cases bulls that are destined for these markets are usually finished intensively indoors on high-concentrate rations.
One point of interest from this system that was raised, before conducting the study, was how finishing bulls from pasture would decrease the cost of production – but would this affect meat eating quality?
Researching eating quality of beef
To dive further into this query, the research carried out examined spring-born, late-maturing breed suckler bull weanlings that were offered grass silage ad-libitum, and daily 2kg concentrates per head during the winter period.
These males were then assigned to one of four experimental treatments until they were slaughtered 200 days later at an average age of 19.3 months.
Although none of the grazing groups achieved the current market specification for carcass fat score, this was not reflected in inferior eating quality.
The treatments for bulls in the study were as follows:
- Grazed grass for 100 days, then concentrates plus grass silage ad-libitum indoors for 100 days (G0AL);
- Grazed grass supplemented with concentrates (0.5 dietary Dry matter intake (DMI)) for 200 days (G50G50);
- Grazed grass for 100 days, then supplemented with concentrates (0.5 dietary DMI) at pasture for 100 days (G0G50);
- Grazed grass only for 200 days (G0).
Once the bulls were slaughtered, their carcasses were weighed and graded for conformation and fatness.
After 48 hours, Longissimus thoracis (striploin) colour was measured. After 14 days’ ageing, striploins were assessed for eating-quality characteristics by trained assessors.
Carcass weight averaged; 399kg; 381kg; 374kg; and 361kg for G0AL; G50G50; G0G50; and G0 bulls, respectively.
Corresponding carcass fat scores were; 7.5; 5.1; 5.5; and 4.8 – only G0AL exceeded the minimum fat score specification of 2+. Meat from bulls finished at pasture tended to be darker, but the differences were small.
The results from the study illustrated that there was no difference in tenderness, flavour or acceptability, between striploin steaks from any of the treatment groups.
The report concluded that although none of the grazing groups achieved the current market specification for carcass fat score, this was not reflected in inferior eating quality, implying that carcass fat score is a poor indicator of the eating quality of bull beef.