تقدير التركيب الكيميائي لعظام الابقار والاغنام والدجاج وامكانية استعمال دھونھا اقتصاديا

DETERMINATION OF THE CHEMICAL COMPOSITION OF THE COWS, SHEEPS an‎d CHICKENS BONES an‎d THE POSSIBILITY OF USING THEIR FAT ECONOMICALLY.

This study includes applying chemical tests on cow, sheep and chicken bones including both hallow and flat. The results of chemical tests on bones mentioned the moisture percentage which was between 4.95-7.32 %, and it was noticed the difference in protein percentage among different kinds of bones, The highest protien percentage was 39.62 % in hallow chicken bones and the lowest was in hallow sheep bones 20.31%, at the same time, the highest Ash percentage was in hallow sheep bones48.11% , whereas the highest percentage of fat was in hallow cow bones 30%. The chemical and physical tests were conducted for extracted fat from hallow and flat bones for cows, sheeps and chicken. It was found that peroxide values (PV), and free fatty acids (FFA) tended to increase proportionally with extraction time at temperatures examined. The lowest values ware obtained after 3 hours as PVs were 0.93, 1.2, 1.0, 1.0, 1.33 and 1.46 meq/ kg oil respectively, FFA values were 0.15, 0.168, 0.187, 0.168, 0.206 and 0.225% respectively. The highest chemical indices for extracted fat from hallow and flat bones for cow and sheep was after 5 hours as PVs were 2.39, 1.8, 1.9, and 1.86 meq/ kg oil respectively, FFA values were 0.253, 0.300, 0.263 and 0.30% respectively. While, the highest chemical indices for extracted fat from hallow and flat chicken bones was after 4 hours, as PVs were 1.6 and 1.73 meq/ kg oil respectively, FFA values were 0.245 and 0.244% respectively. The obtained results showed values of smoking point tended to decrease proportionally as extraction time proceeding at different temperature used, highest values were recorded after extraction for 3 hours, smoking point values were 242.6, 231.33, 223.8, 217.66, 204.5and 204 °C respectively. The lowest physical values of fat extracted from hallow and flat bones of cow and sheep were obtained after 5 hours as the smoking point values were 230.33, 229.83, 203.4 and 204.83°C respectively. The lowest physical indices of fat extracted from hallow and flat chicken bones were obtained after 4 hours, as the smoking point values were 204 and 203.5 °C respectively.