Meat quality of wether lambs grazed on either saltbush (Atriplex nummularia) plus supplements or lucerne (Medicago sativa)

The meat quality of 42, 8 month-old cross-bred wether lambs that had been g razed on either predominantly saltbush (Atriplex nummularia) and supplement ed with pasture hay (n=14) or oat grain (n=14) for 68 days was compared to lambs grazed predominantly on lucerne (Medicago sativa; n = 14). The lambs used in the study ranged in un-fasted liveweight from 44.5 to 63.6 kg pre-s laughter. There was no significant (p > 0.05) difference between the treatm ents for liveweight, but there was a significant (p < 0.05) treatment effec t on hot carcass weight with those from the saltbush/hay group (SH) being l ighter than those from the lucerne group. When the carcass measures of fatn ess or m. longissimus thoracis et lumborum area were adjusted to a common c arcass weight of 22.4 kg there was no difference between groups. There were no significant differences (p > 0.05) between groups for pH or colour valu es (where L* indicates relative lightness, a* indicates relative redness an d b* indicates relative yellowness). There was no significant difference (p > 0.05) between groups for b(2)* values of subcutaneous fat. Treatment had a significant effect on aroma strength (p < 0.05), samples from lambs in t he SH group (n = 10) and those in saltbush/grain (SG) group (n = 10) having a stronger aroma than those from lambs grazed on lucerne (L; n = 10). No t reatment effect for liking of aroma was found. Flavour strength was not sig nificantly (p > 0.05) stronger for samples from groups SH and SG than for s amples from group L. There was no effect of treatment on tenderness or juic iness and overall panellists ranked the samples similarly for acceptability . Finishing lambs on saltbush and either supplemented with hay or grain as used in this experiment did not present any apparent meat quality problems compared to lucerne fed lambs. (C) 1998 Elsevier Science Ltd. All rights re served.