Fresh meat and further processing characteristics of ham muscles from finishing pigs fed ractopamine hydrochloride

Abstract

Ractopamine hydrochloride (RAC) has consistently led to an advantage in carcass cutting yields of finishing pigs and remains a common feed additive in US finishing pig diets. Less is known about the effect of RAC on further processing characteristics. Some researchers have reported advantages in ultimate pH of the LM in pigs fed RAC. If a greater ultimate pH was also observed in hams, the increased pH could affect further processing characteristics and lead to better protein interaction and improved textural properties. The objective of this experiment was to determine if RAC-fed pigs yielded hams with a greater ultimate pH, and if so, whether or not that advantage improves textural properties and water retention of further processed hams. Two hundred hams from barrows and gilts fed RAC or control diets were selected based on HCW. Hams were fabricated into 5 separate pieces to determine cutting yields, and 6 muscles were evaluated for ultimate pH. Hams were processed to make cured and smoked hams. Ractopamine increased cutting yields of the whole ham (P < 0.0001), inside (P < 0.01), outside (P < 0.01), and knuckle (P < 0.01) when expressed as a percentage of chilled side weight. Ultimate pH of the rectus femoris, vastus lateralis, and semitendinosus were all 0.06 pH units greater (P < 0.05), the biceps femoris was 0.04 pH units greater (P = 0.02), and the semimembranosus and adductor muscles were 0.03 pH units greater in pigs fed 7.4 mg/kg of RAC when compared with control pigs. Cured hams from RAC-fed pigs were heavier at all stages of production. No differences were detected in binding strengths (P = 0.88) or protein fat-free values (P = 0.13) between RAC (9.06 kg and 20.37) and control hams (9.01 kg and 20.13). Ractopamine increased cutting yields, total weight of cured hams, and ultimate muscle pH. Ractopamine can be fed to pigs to achieve the desired growth characteristic advantages and cutting yields without affecting further processed ham characteristics.

Ractopamine as a metabolic modifier feed additive for finishing pigs: a review

“…However, reductions in fat deposition induced by ractopamine have not been clearly observed (Dunshea et al 1993(Dunshea et al , 1998Carr et al 2005b;Fernández-Dueñas et al 2008;Moore et al 2009;Boler et al 2010;Kutzler et al 2010). Because literature reports regarding the effects of ractopamine on fat accretion are inconclusive, in vitro assays were developed to explain the possible irresponsiveness of ractopamine in adipose tissue metabolism.…”

“…Consumer demand for leaner and healthier pork products has risen steadily each year; thus, improvements in animal health, genetics, and especially nutritional technologies, such as the utilization of β-adrenergic agonists in diets, have become important in helping pork producers to meet this demand. In addition to their use in human and veterinary medicine as bronchodilatory and tocolytic agents (Kuiper et al 1998), β-adrenergic agonists increase both lean growth rate and carcass lean percentage (Boler et al 2010), and improve feed efficiency of finishing pigs (Rikard-Bell et al 2009;Hinson et al 2011). Ractopamine is classified as a β-adrenergic agonist that acts as a repartitioning agent, redirecting nutrients away from adipose tissue and towards greater muscle deposition.…”

Effects of ractopamine hydrochloride and immunological castration in pigs. Part 2: belly quality characteristics and fatty acid composition

“…These results favor the addition of ractopamine in pig diets, considering that the use of β agonists could cause a high level of stress to the animal and develop PSE meat (Pale, Soft and Exudative) or stimulate glycolysis, thereby promoting ante-mortem muscular glycogen consumption, resulting in accumulation of lactic acid in the carcass after slaughter (Boler et al, 2010), which would be detected by a pH decrease, not observed in the present study.…”

Ractopamine-induced changes in sarcoplasmic proteome profile of post-rigor pork <i>semimembranosus</i> muscle

“…It is well documented that dietary ractopamine increases carcass weight in finishing pigs (Stites et al, 1991;Armstrong et al, 2004;Fernandez-Duenas et al, 2008). Furthermore, an increase in the weight of inside ham (consisting of semimembranosus muscle) was observed in ractopamine-fed pigs (Boler et al, 2011). The increased muscle growth due to ractopamine could possibly demand increased levels of plasma membrane repair proteins to maintain homeostasis.…”

“…Ractopamine is a beta-agonist approved for use in swine industry to increase growth rate, feed efficiency, carcass yield, and leanness in finishing pigs (Apple et al, 2007;Dunshea, 2012;Pompeu et al, 2017) in more than 25 countries, including the United States, Canada, Australia, Mexico, Philippines, Brazil, sand South Korea (AMI, 2012). Dietary ractopamine increases leanness (Boler et al, 2011) and carcass weight (Stites et al, 1991;Armstrong et al, 2004;Fernandez-Duenas, 2008;Needham & Hoffman, 2015) in pigs, and the increased carcass weight is a consequence of the increase in myofibrillar protein synthesis (Adeola et al, 1992).…”