INFLUENCE OF pH AT 24 H POSTMORTEM ON QUALITY CHARACTERISTICS OF PORK LOINS AGED 45 DAYS POSTMORTEM

Abstract

ABSTRACT Boneless pork loins (n = 81) were used to determine the influence of pH and chop location on longissimus muscle (LM) quality characteristics of loins aged until 45 days postmortem. Loins were grouped into five pH categories from 24‐h pH measurements. Chop L* and b* values linearly decreased with increasing pH. Visual scores for LM chops linearly increased (deteriorated in color) with days of display. Chops with pH values from 5.6 to 5.9 were the most color stable. Percentage of purge and cooking loss linearly decreased with increasing pH. Bacterial population increased as pH increased. Chops with a pH of 5.5 or lower had the highest L* and b* values, most cooking loss and most total moisture loss, compared with all other pH groups. Therefore, pH measurements at 24 h postmortem can be used to predict color and other quality characteristics of pork loins aged until 45 days postmortem.PRACTICAL APPLICATIONSTwenty‐four hour pH can be used to predict quality characteristics and retail display color stability of chops from loins after prolonged periods of storage. Therefore, loins can be sorted and selected for prolonged storage conditions required by transportation using 24‐h pH. Loins with pH values from 5.6 to 5.9 can be selected for extended retail display color stability, while low and high pH chops may need to be sold more rapidly or further processed earlier to maintain value.