In other words, ES may turn on some of the enzymes that make meat more tender during the conditioning period. Contralateral differences in the effectiveness of ES may be detected when one hindlimb is shackled and the other side moves freely. The time delay between exsanguination and stimulation has been extended up to 60 minutes, during which time carcasses have received variable treatments such as evisceration and splitting. Stimulation during exsanguination is not effective. Impulse frequency and duration of application range from 3 to 400 Hz.
Muscles differ in the optimum frequency required for their maximum stimulation.
Wave forms of stimulatory impulses have included square waves of interrupted direct current unchanged or partly modified sinusoidal waves of alternating current. ES and the Nervous System. Even in a simplified laboratory model of carcass stimulation, with a muscle strip and a pair of stimulatory electrodes, the response of necrobiotic muscle may be quite complex. Although stimulation may accelerate post mortem metabolism, muscle with an already accelerated rate of metabolism may lose its excitability at a faster than normal rate. Thus, animals with intrinsically fast glycolytic rates may be detected by their reduced electrical excitability .