Med. Weter. 69 (7), 424-427, 2013

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Bernacka H., Peter E., Mistrzak M.
Fatty acid content in meat, heart, and liver of conventionally bred Polish Merino lambs
The objective of our research was to establish differences in fatty acid profiles of fat in the muscle tissue and selected edible organs (liver, heart) of conventionally bred Polish Merino lambs. The importance of this research stems from the fact that the sheep products under analysis are considered to be functional food. Our research material consisted of 20 Polish Merino lambs from a conventional herd. Ram lambs were slaughtered at the age of 100 days (at weaning), when they weighed 26-28 kg. The fatty acid content was determined in the longissimus dorsi muscle, leg, liver and heart, by the Röse-Gottlieb method, according to AOAC 905.02, with a Hewlett-Packard 6890 gas chromatograph. Analysing the fatty acid profiles of lamb muscles and offal, we found that the general content of saturated fatty acids (SFA) was the lowest in the heart (48.36%), significantly higher in the liver (58.37%), longissimus dorsi muscle (57.25%), and adductor femoris (56.17%). Unsaturated fatty acids (UFAs) constituted 51.64% of total acids in the heart, where their content was higher than in the liver, in the sirloin and in the leg by 10.01 percentage points (pp) 7.89 pp and 7.81 pp respectively. The differences were confirmed statistically. An increased percentage of unsaturated acids contributed to better ratios of UFA/SFA and PUFA/SFA, which amounted, respectively, to 1.07 and 0.43 for the heart, and to less than 1.00 and 0.30 for the other tissues, testifying to a high nutritional value of the heart. A comparative analysis of the results has shown that, from the nutritional point of view, the most favourable fatty acid composition – that is, the lowest content of saturated fatty acids and the highest of unsaturated fatty acids – as well as a favourable UFA/SFA ratio, was found in the heart, followed by muscles and the liver. We can conclude that meat and offal from conventionally bred lambs, fed on the mother’s milk and the farmer’s own crops, without genetic modifications qualify as wholesome products with high nutritional and health value.
Key words: lambs, meat, offal, fatty acids