EFFECT OF MgCl₂/SODIUM PYROPHOSPHATE ON CHICKEN BREAST MUSCLE MYOSIN SOLUBILIZATION AND GELATION

Abstract

Sodium chloride (0.29 M) at pH 7 solubilized about 24% of the myosin of washed, minced chicken breast muscle. At a similar pH, 0.2 M sodium chloride in the presence of 10 mM sodiumpyrophosphate and 10 mM magnesium chloride solubilized almost 60% of the myosin. In spite of the greater solubility of myosin under the latter conditions, when gels were prepared with these concentrations of salt at pH 7, the gels without the sodium pyrophosphate and magnesium chloride were slightly superior in both stress (39.3 kPa vs 28.3 kPa) and true strain (2.3 vs 2.0) values. Gels made at a lower pH (6.1–6.5) made much poorer gels. This was true whether the low pH was obtained naturally in the preparation of the sample or re‐adjusted after bringing the mince to a neutral pH. It appears that conditions of pH and salt content that cause solubilization of myosin at more dilute conditions does not contribute to gel quality, but the neutral pH is an important factor for obtaining good gels at ionic strengths <0.3.

Factors Influencing Gel Formation by Myofibrillar Proteins in Muscle Foods

“…Sodium chloride is the salt commonly used in commercial reformed meats. It is generally accepted that a high concentration (2% to 3%) of sodium chloride is required to solubilize the MPs and fully develop the functional properties of muscle tissue foods (Xiong and Brekke 1991), but Chang and others (2001a, 2001b) and Feng and Hultin (2001) concluded that solubilization of the MPs was not an absolute necessity for gel formation by MPs. Assuming that lean meat skeletal muscle contains 75% water, molar concentrations of salt calculated from those percentages (2% to 3%) give 0.47 to 0.68 M (Ishioroshi and others 1979).…”

Changes in Some Biochemical Indices of Stability of Broiler Chicken Actomyosin at Different Levels of Sodium Bicarbonate in Presence and Absence of Sodium Chloride

“…[41,42] NaCl is fairly effective in solubilizing substantial amount of major myofibrillar proteins at 2.5% concentration. [42−44] For instance, ∼90% actomyosin proteins were solubilized from Pacific white shrimp at 0.2M NaHCO 3 .…”