Carcass chilling method and electrical stimulation effects on meat quality and color in lamb

Five treatments: Control (C), Pre-evisceration Electrical Stimulation (CES: 15 Hz, 700 mA, 500 mu s pulse width, 45 s pulse duration), vascular Rinse & Chill (R) (RC), CES + RC (ESRC), and RC with ES after evisceration (RCES:15 Hz, 600 mA, 1000 mu s, 45 s), were applied to 21 lambs each. After being excised from the carcass, muscles were vacuum packaged and aged (Longissimus lumborum, LL, 3 and 22 d postmortem; Semimembranosus, SM, 3 d postmortem). Temperature, pH, purge, cooking loss, color, Warner-Bratzler Shear Force (WBSF), and consumer sensory evaluations were determined. CES and ESRC resulted in the fastest drop in pH below 6 and ESRC had the lowest likelihood of cold shortening. Sensory tenderness in the ESRC LL was greater than C. No differences in WBSF were found among treatments. RC generally produced lamb with higher lightness (L*). The rapid drop in pH likely was responsible for the increased purge and cooking loss observed. Color was affected by the order of ES and RC application.