Chicory grazing produced heavier lambs with better killing out percentages
Take Home Message: Finish lambs on pasture containing chicory produce heavier carcasses and ‘juicier’ meat than those finished on perennial ryegrass/clover.
Grazing lambs on chicory produces heavier carcases with a better killing out percentage. Female lambs also demonstrated increased loin juiciness. These were just two of the findings of a trial, carried out by UK scientists, which were presented to delegates at this year’s British Society of Animal Science’s annual conference, held at Queen’s University, Belfast.
A growing body of evidence shows that lambs grazing pure stands chicory grow faster, finish earlier in the season, and have lower levels of parasitism. “However, it is not known if chicory affects meat eating quality, although carcasses may be leaner when market weights are reached, compared to a more slowly finishing on grass/clover mixtures,” said the Scottish Agricultural College’s Jos Houdijk, who led the trial.
“Dietary influences on meat quality should be considered as these are very relevant for consumer acceptance. So we set out to assess the effect of chicory grazing on killing out percentage and meat eating quality in lambs.”
Lambs grazed pure stands of chicory (CH) or grass/clover (GC) from turn-out at 32 days of age for 20 weeks. Body weight was taken just before slaughter. Carcasses were hip-suspended at 2°C for 24 hours before posterior 20cm of left loins were retrieved, matured at 2°C for another nine days in vacuum bags and frozen pending sensory quality assessment at the University of Bristol.
Loins were thawed overnight, de-boned on the day of assessment, cut in 8-10 2-cm thick samples and cooked until internal temperature reached 75°C. Samples were placed in an incubator (60 ºC) prior to sampling by 10 qualified assessors, who were asked to rate it on eight-point category scales for tenderness, juiciness, lamb flavour intensity, abnormal lamb flavour intensity and two hedonic scales for flavour liking and overall liking.
“And we found that chicory grazed and grass and clover grazed lambs weighed 39.1kg and 36.4kg respectively. Killing out percentages were 39.9% and 37.2% respectively,” said Dr Houdijk.
His team also found that female chicory-grazed lambs had juicier loins than grass-and-clover grazed lambs with reduced grassy flavour. However, in some sub-panels, effects on juiciness were stronger and CH loins were scored as being tenderer than GC loins, with a higher livery flavour.
“Beneficial sensory scores for eating quality were given to chicory-reared lamb in several sub-sets, but these were cancelled out when data was pooled, suggesting the need for relatively large numbers of observations to avoid drawing invalid conclusions,” stressed Dr Houdijk.
“Although it can not be excluded that sex-specific effects observed in this study would not be present had lambs been finished to commercial standards, overall the data suggest that using chicory as an alternative crop for finishing lambs is expected to yield higher carcass weights without detrimental effects on meat eating quality,” he added.
Presented to the British Society of Animal Science Annual Conference, 12-14 April, 2010, Queen’s University, Belfast.
Houdijk JGM, Nute GR, Navajas EA, Richardson RI and Ross DW: “Effect of chicory grazing on killing out percentage and meat eating quality in lambs.”
To view proceedings of all summaries presented at the Annual Conference 2010 http://www.bsas.org.uk/Publications/Annual_Conference_Proceedings/ To view all Powerpoint presentations http://www.bsas.org.uk/Members_Area/
For further information contact: BSAS on 0131 445 4508 or bsas@sac.ac.uk
