J. Guidera et al., THE EFFECT OF DIETARY ALPHA-TOCOPHERYL ACETATE SUPPLEMENTATION ON MUSCLE ALPHA-TOCOPHEROL LEVELS AND LAMB QUALITY, Irish journal of agricultural and food research, 36(2), 1997, pp. 241-247
The effects of dietary alpha-tocopheryl acetate supplementation on the
uptake of alpha-tocopherol in lamb M. triceps brachii caput longum, M
. biceps brachii, M. gluteus medius and M. semimembranosus and on the
oxidative and colour stability of frozen M. semimembranosus were inves
tigated. Pregnant ewes (n = 12) were divided into two groups (n = 6).
The control group was fed a diet containing 20 mg alpha-tocopheryl ace
tate / kg feed / day and the supplemented group fed a diet containing
1000 mg alpha-tocopheryl acetate / kg feed / day, for 9 weeks pre-part
um and 3 weeks post-partum. Lambs were weaned at 3 weeks of age and fe
d supplemented or basal feed for 10 weeks prior to slaughter. Suppleme
ntation increased the alpha-tocopherol levels in all tissues sampled.
Frozen storage, at -20 degrees C for 36 weeks, reduced the mean alpha-
tocopherol levels in all muscles. Reduction was statistically signific
ant (P < 0.05) only in M. semimembranosus. Supplementation significant
ly (P < 0.05) inhibited induced lipid peroxidation in frozen (-20 degr
ees C for 22 weeks) and thawed (4 degrees C x 12 h) M. semimembranosus
. Surface discoloration of frozen M. semimembranosus during subsequent
refrigerated display was not affected by supplementation. However, a
significant (P < 0.05) decrease in the proportion of metmyoglobin was
noted after 6 days of storage.