Gelatin had been processed from bones, heads. legs and skin which got from spent hens. The samples were cleared, cut and getting rid of oil by boiling then the removal of mineral salts was done by6% hydrochloric acid for 24 hours . After that samples were soaked in diluted base (0.2N NaOH ) for 18 hours and wash with water. The process of extracting was done by damp heating in an electric oven at various temperatures 65 , 75 and 85 Celeries with both time periods 10 and 20 hours. After that, the process of clarification , filtration and drying the gelatin solutions were mille red, filtrated and dried, then they grinded and filling. The functional properties had been studied and the results referred to the following
- Processed gelatin had good functional properties and near to the commercial gelatin , hence it had highly percentage of solubilility ( 95.29 – 96.95 % ).
-The processed gelatin had best ability to make foam ( 176.6 ml ) for head gelatine and ( 157.6 ml ) for leg gelatin , and also had best foam stability after 5 minutes .
- The processed gelatin had good ability to absorb water and oil , hence the absorbed water ranged from( 2.67- 7.83) ml water / gm gelatin and the amount of absorbed oil ranged between(1.02 – 2.58) ml oil / gm gelatin.
- Processed gelatin had good viscosity compared with the commercial gelatin , the total of viscosity were ( 1.229 centi poise ) ,as well as types gelatin processed had good ability of emulsion with high stability. The gelatin processed have good gelation in ( 2 – 3 % ) concentration.
- The powder color graded from transparent color to brown. In sensory evaluation, all the prepared samples of gelatinous desert gained the degree of very acceptable ( 81 , 82 , 83 and 83.5 ) for the desert prepared from the gelatin of head , legs , bones and the skins ,respectively. .