EFFECTS OF LOW VOLTAGE ELECTRICAL STIMULATION AND CHILLING METHODS ON QUALITY TRAITS OF PORK M. LONGISSIMUS LUMBORUM

Abstract

ABSTRACT The effects of low voltage electrical stimulation and chilling methods on the quality aspects of pork carcasses were evaluated in this study. A total of 16 pigs (Long white × Huainan) were randomly allocated immediately prior to slaughter to two groups: low voltage electrically stimulated (LVES or ES) or nonstimulated (NS). Carcasses were split before cooling. Each side of the carcass was then randomly allocated to either conventional chilling or blast chilling. Results showed that LVES increased the rate of muscle pH decline in the early time postmortem and accelerated the onset of rigor. But LVES with conventional chilling had disadvantageous effects on water‐holding capacity (WHC), Warner‐Bratalor shear forces and lightness of meat color. However, LVES combined with blast chilling can avoid this disadvantage. And blast chilling achieved low internal muscle temperature faster than with conventional chilling and delayed the rate of muscle pH decline. Furthermore, blast chilling increased WHC of pork without risk of cold toughing. The disadvantageous effect of LVES on pork quality can be equalized by the advantageous effect of blast chilling. Therefore, it is desirable for commercial pig abattoirs to apply blast chilling, or low voltage electrical stimulation combined with blast chilling for rapid processing without compromising meat quality.PRACTICAL APPLICATIONSThere are many pork quality characteristics (i.e., appearance, texture and flavors as well as tenderness, juiciness and other subjective characteristics) that attract consumer attention. Among these, the water‐holding capacity of the pork, color and tenderness are considered the most important quality characteristics. Postmortem treatments involved with the postmortem biochemical process influence pork qualities. Therefore, investigations into the effects of electrical stimulation of pig carcasses, chilling methods, suspension and their combinations on pork qualities should be prerequisites for improving pork qualities.