Can different finishing methods affect meat quality?

At the recent Teagasc beef conference, Prof. Donagh Berry outlined that consumers can take up to three months to buy beef after a bad eating experience. Therefore, there is a monetary value for tenderness and meat quality characteristics.

Bull-beef production is popular among Irish farmers, with markets requiring a fat score of 2+ or better. These systems involve finishing these bulls on a high-concentrate diet under 16 months.

However, these finishing systems are expensive and animals on an intense feeding regime need to be fed efficiently.

Naturally, the presence of grazed grass or grass silage in the diet lowers the cost of production. However, achieving the desired fat score without high levels of concentrates is difficult within the time frame.

Recent research in Teagasc, Grange, Co. Meath has evaluated lower-cost production systems in terms of bull performance and meat quality.

For the purpose of this study, spring-born, late-maturing breed suckler bulls – weighing 375kg – were offered grass silage ad-lib and concentrates at a rate of 2kg/head/day during the winter period.

Following on from this, the bulls were then assigned to one of four experimental diets and environments until slaughter at an average age of 15 months.

The four diets and environments included:
  • Concentrates fed indoors ad-lib with grass silage (1);
  • Grass silage fed indoors ad-lib with 5kg of concentrates (2);
  • Grazed grass and 50% of dry matter intake (DMI) in the form of concentrates (3);
  • Grazed grass only (4).

Post slaughter, all carcasses were weighed and graded for conformation and fat score. After a period of 48 hours, striploin cuts were measured for ultimate pH and colour. After being aged for 14 days, these striploin steaks were then inspected by trained assessors.

As would be expected, carcass weights averaged 358kg, 315kg, 288kg and 277kg for diet and environment one, two, three and four respectively. In addition, the fat scores (on the zero-to-15 scale) were 7.2, 6.0, 4.2 and 3.6 respectively.

The beef from grazed animals was darker than that from indoors bulls; however, no differences were found in ultimate pH. Sensory characteristics did not differ between striploin steaks from the bulls on diet and environment one or grazing bulls.

Furthermore, striploin steaks from the second group were rated most tender, but the difference from the other diets was small.

Finally, as would be expected, neither of the grazing groups achieved the current market specification for carcass fat score, but it was not reflected in the inferior eating quality of the beef.