Dynamic rheology and endothermic transitions of proteins recovered from chicken-meat processing by-products using isoelectric solubilization/precipitation and addition of TiO2

• Published in: Food science & technology 2012-04, Vol.46 (1), p.148-155
• Main Authors: Tahergorabi, Reza, Sivanandan, Litha, Jaczynski, Jacek
• Format: Article
• Language: English
• Subjects: Animal productions; Biological and medical sciences; Chicken muscle proteins; Differential scanning calorimetry; Dynamic rheology; Food industries; Fundamental and applied biological sciences. Psychology; Isoelectric solubilization/precipitation; Meat and meat product industries; Protein functional properties; Shear stress and strain; Terrestrial animal productions; Vertebrates
• ISSN: 0023-6438; 1096-1127
• DOI: 10.1016/j.lwt.2011.10.013

Chicken-meat processing generates large quantities of by-products (backs, necks, etc.). Dark chicken-meat processing by-products present the lowest value and greatest challenge. Therefore, recovery of functional proteins from this source for inclusion in food products resembling those from light chicken-meat presents the greatest value addition and opportunity. Novel isoelectric solubilization/precipitation (ISP) was applied to model, dark chicken-meat processing by-products (skin-on bone-in chicken drumsticks) to recover muscle proteins. Thermal denaturation (endothermic transitions), gelation (elasticity, G′), and fundamental texture properties (shear stress and strain at mechanical fracture) of the ISP-recovered proteins were determined with differential scanning calorimetry (DSC), dynamic rheometer, and torsion test, respectively; and compared to boneless skinless chicken breast. Endothermic transition of myosin was not detected only when TiO2 was not added, while the ISP-recovered proteins with TiO2 showed small myosin peak and large actin peak. However, the level of TiO2 addition did not affect thermal transition/denaturation of the ISP-recovered proteins. The ISP-recovered proteins had a greater transition for actin compared to chicken breast, suggesting that ISP predisposes this protein to thermal denaturation. Similar to endothermic transitions, elasticity (G′) generally increased when TiO2 was added to the ISP-recovered proteins. Gels made of chicken breast had the highest (P