The study examined and compared the fatty acid profiles, meat quality, sensory attributes, and consumer acceptance of beef from dairy steers raised using either conventional, organic, or grass-fed organic methods.
Led by corresponding author Bradley Heins from the University of Minnesota, the team revealed that the fat from the grass-fed steers was greater in omega-3 fatty acids and lower in monounsaturated and saturated fat, but noted that consumers rated the grass-fed beef the lowest in overall liking and flavour.
"As consumers are demanding natural, local, organic, and grass-fed animal products, an opportunity exists for organic dairy producers to capitalize on the growing organic beef industry," wrote the team.
Despite the finding that grass-fed organic meat was the lowest in terms of consumer acceptability in the USA, the team did note that 43.9% of consumers had at least a slight liking for the grass-fed steaks.
"Organic dairy bull calves may represent a potential resource for pasture-raised beef ... an alternative to conventional feedlot-raised beef," they said.
However, Heins and his colleagues noted that the quality and consistency may need to be improved before consumers will accept the beef.
Heins and his colleagues noted that the majority of beef consumers in the US prefer the taste of conventional grain-fed beef - adding that the United States cattle industry most commonly finishes animals on a corn-based ration.
"Conversely, in the European Union, beef consumers assert that meat from livestock managed under less intensive production systems has superior taste than meat from intensive production systems," they said.
Forty nine bull calves were randomly assigned to 1 of 3 replicated groups: conventional (CONV), organic (ORG, pasture + concentrate), or grass-fed organic (GRS).
The CONV steers (n = 16) were fed a diet that contained 80% concentrate and 20% forage, while ORG steers (n = 16) were fed a diet of organic corn, organic corn silage, and organic protein supplement.
"Furthermore, ORG steers consumed at least 30% of diet dry matter of high-quality organic pasture during the grazing season," added the team.
Meanwhile, GRS steers (n = 17) consumed 100% forage from pasture during the grazing season and high-quality hay or hay silage during the nongrazing season, they said.
The team reported that organically raised (ORG group) steers had fat that was greater in oleic acid when compared to both GRS and CONV steers.
Levels of monounsaturated fats were lowest in the GRS group steers (21.9%), when compared to ORG (42.1%) and CONV (40.4%) steers.
"Furthermore, the GRS steers tended to have greater omega-3 fat and had lower omega-6 fat than the ORG and CONV steers," added Heins and his colleagues. "Consequently, the GRS (1.4%) steers had a lower n-6-to-n-3 fat ratio than the ORG (12.9%) and CONV (10.0%) steers."
In terms of sensory attributes (rated on a 0- to 120-point scale), no differences were found between ORG (71.3) and CONV (69.2) steers for overall consumer liking of the beef; however, the GRS (56.3) steers had the lowest overall liking among beef consumers.
"The ORG (73.3) steers had greater flavour liking than the GRS (56.8) and CONV (69.2) steers," they said. "Conversely, the GRS (6.3) steers had the highest scores for off-flavor (0- to 20-point scale) compared with the ORG (3.9) and CONV (4.1) steers."
Source: Journal of Dairy Science
Volume 97, Issue 3, Pages 1828–1834, doi: 10.3168/jds.2013-6984
"Fatty acid profiles, meat quality, and sensory attributes of organic versus conventional dairy beef steers"
Authors: E.A. Bjorklund, B.J. Heins, A. DiCostanzo, H. Chester-Jones