Thermal gelation characteristics of breast and thigh muscles of spent hen and broiler and their surimi

Spent hen (98 weeks) and broiler (12 weeks) breast and thigh muscles were m inced (1 mm orifice diameter) and washed with 0.1% NaCl. A portion of both unwashed and washed mince was mixed with cryoprotectants (CP) at the rate o f 4% sucrose, 4% sorbitol, and 0.2% Na-tripolyphosphate to produce surimi a nd kept frozen at -20 degrees C. The mince and surimi were ground with 3% N aCl and a small amount of water to adjust the final moisture content of 80% . The pastes were stuffed into the sausage casing and heated at 90 degrees C for 15 min to produce gel. The effects of washing, heating and CP on colo ur composition and thermal gelation properties of hen and broiler minces an d surimi were compared. Broiler mince was lighter and less red in colour, h igher in protein and lower in moisture, lipid and collagen. Gel strength an d breaking strength were higher in spent hen surimi compared to broiler sur imi under similar gelation conditions. Gel elasticity, springiness and wate r retention properties were almost identical in two surimi. Gel quality was markedly deteriorated in spent hen surimi but not so in broiler surimi aft er 8 weeks frozen-storage. Although CP increased the gel strength of fresh surimi (non-frozen, 0 week storage) from both hen and broiler, they were mo re effective in broiler surimi than hen surimi in protecting the functional quality of gel. (C) 1999 Elsevier Science Ltd. All rights reserved.