Effects of electrical stimulation on early postmortem muscle pH and temperature declines in pigs from different genetic lines and halothane genotypes

The objective of this study was to determine if electrical stimulation (ES) early postmortem is an effective method to generate PSE-like meat. One hun dred and thirty-eight gilts (85-125 kg) from heavy muscled (HM), normal mus cled (NM), and light muscled (LM) porcine genetic lines were subjected to o ne of two treatments: ES (26 pulses of 500 V, 60 Hz) at 3 min postmortem or non-stimulated (NS). Pigs from HM line were further characterized as halot hane (HAL) carriers (Nn) or non-carriers (NN). ES carcasses had lower (P < 0.0001) pH values and higher (P < 0.0001) temperature than NS carcasses dur ing the first 56 min postmortem. ES carcasses had lower (P < 0.0001) a*-val ues, and color and firmness scores, as well as higher (P < 0.0001) drip los s and L*-values. No significant interactions were found between treatment a nd genetic line or HAL gene status with regard to pH, temperature, or quali ty characteristics. Temperature and pH declines within the first hour postm ortem were not affected by genetic line, but slight (P < 0.01) quality diff erences were observed. Nn and NN did not differ in pH or temperature within the first hour postmortem, but Nn carcasses had lower (P < 0.01) color and firmness scores, and higher (P < 0.05) drip loss. These results show that ES early postmortem is an effective method for simulating PSE development i n pigs of different muscling and HAL gene status, and suggest that pH and t emperature decline alone cannot explain all aspects of pork quality. (C) 19 99 Elsevier Science Ltd. All rights reserved.