Heat-induced gelation properties of chicken breast muscle salt soluble proteins when mixed with β-lactoglobulin or an α-lactalbumin enriched protein fraction

• Published in: Meat science Vol. 48; no. 1; pp. 135 - 147
• Main Authors: Smyth, A.B., McCord, A., O'Neill, E.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 1998; Elsevier
• Subjects: Animal, plant, fungal and microbial proteins, edible seaweeds and food yeasts; Biological and medical sciences; Food industries; Fundamental and applied biological sciences. Psychology; Colloidal gel; Vertebrata; Lactoglobulins; Lactalbumin; Gelation; Animal protein; Environmental factor; Chicken; Technological properties; Aves; Water holding capacity; Rheological properties
• ISSN: 0309-1740; 1873-4138
• DOI: 10.1016/S0309-1740(97)00084-3

The heat-induced gelation properties of mixed protein systems containing chicken breast muscle salt-soluble proteins (SSP) and β-lactoglobulin (β-lg) or SSP and an α-lactalbumin-enriched fraction (α-la) in 0.6 M NaCl, pH 6.5, were investigated using dynamic rheology. At 70 °C, SSP had greater storage modulus (G′) values than mixtures containing SSP/α-lg. However, at 90 °C, mixtures containing 80:20 and 60:40 SSP: β-lg had higher G′ values than SSP alone, indicating that denaturation of β-lg directly or indirectly facilitates the formation of a more rigid gel structure. On subsequent cooling to 20 °C, the extent of structure formation, as reflected by G′ values, was greater for SSP than for mixtures containing SSP/β-lg, which suggests that the denatured β-lg is unable to interact with the SSP during cooling. Mixtures containing SSP and an α-la-enriched fraction had lower G′ values than SSP at 90 °C and on subsequent cooling to 20 °C, which reflects the poor gelling properties of α-la. A fibrous network was observed when the microstructure of the SSP and 40:60 SSP: α-la gels were examined using scanning electron microscopy, while aggregated networks were seen in the β-lg and 40:60 SSP: β-lg gels. No significant differences ( p > 0.05) were observed between the water holding capacity (WHC) of SSP and SSP/β-lg gels. Gels formed from a mixture of SSP and the α-la-enriched fraction had lower WHC than the SSP gels. The myosin heavy chain was a major contributor to gel structure formation in all mixed gel systems.