Effect of Muscle Type and Sodium Tripolyphosphate on Residual Nitrite, pH, Color, and Instron Measurements of Turkey Frankfurters

Six treatment combinations for evaluation of turkey frankfurters were studied – three muscle type combinations (100% white, 50% white-50% dark, and 100% dark) and two sodium tripolyphosphate concentrations (0 and .25%). Cook yield, cooked color, raw emulsion pH, cooked pH, residual nitrite, cured color (nitroso-haemochromogen), and total color (acid haematin) were measured. Texture measurements of the frankfurter skin and interior were made with an Instron Universal Testing Machine with Warner-Bratzler shear and puncture probe attachments. Cook yield was not affected by muscle type or phosphate addition. Hunter L-values (reflectance or light/dark) increased with increasing amounts of white muscle, while Hunter + a values (redness) decreased. Frankfurters made with 100% dark muscle were higher in pH, contained more residual nitrite, and had higher cured color and total color values than frankfurters made with 100% white muscle. Instron Warner-Bratzler shear peak heights and puncture-probe peak heights and areas indicated frankfurters made with 100% white muscle were firmer than frankfurters made with 100% dark muscle. Sodium tripolyphosphate increased frankfurter interior firmness (Instron puncture-probe peak heights), the pH of both raw and cooked samples, and residual nitrite values.