Abstract:

The contents of total protein and salt-soluble protein (SSP) in breast and leg muscles of spent layer ducks were determined and compared with those of broiler ducks. Micro-Kjeldahl method was used to determine the contents of total protein and SSP derived from breast and leg muscles. Also, the emulsifying and foaming capacities of SSP were determined. The total protein contents of breast and leg muscles of broiler ducks and spent layer ducks were approximately 22% and a slight higher content in breast muscle than in leg muscle was observed. The SSP contents in breast and leg muscles of broiler ducks were (24.61±1.19)% and (28.90±1.57)%, respectively; while those of spent layer ducks were (29.09±1.23)% and (27.27± 1.63)%, respectively. The emulsifying capacities of salt-soluble protein in breast and leg muscles of broiler ducks were (51.13 ±2.27)% and (46.53±2.16)%, respectively; while those of spent layer ducks were (50.00±0.73)% and (43.69±2.08)%, respectively. The foaming capacities of salt-soluble protein in breast and leg muscles of broiler ducks were (52.25±2.50)% and (47.67±0.93)%, respectively; while those of spent layer ducks were (54.38±4.27)% and (42.98±1.89)%, respectively.

Key words: spent layer duck, salt-soluble protein, emulsifying capacity, foaming capacity