342 Dietary pecan shell supplementation on feedlot lambs´ meat traits: pH, color, water holding capacity, shear force, and cooking loss.

Abstract Growing interest is in incorporating phytocompounds into animal feeding to modulate meat characteristics and functionality. Many phytocompounds are available, from those used in traditional indigenous medicine to those generated by modern agroindustry as a by-product. The pecan shelling industry generates several by-products from which the pecan shell (PSH) accounts for roughly 50% in mass. Its high tannins content may help to modulate meat characteristics and functionality, however, there is not data on that regard. The objective was to evaluate the influence of PSH supplementation on meat traits. Twelve Pelibuey lambs (48.67 ± 3.72 kg BW) were used in an 84-d feeding trial to evaluate the effect of partial replacement of corn with PSH in a growing-finishing diet on meat quality characteristics. Lambs were distributed in a completely randomized design in two treatments, with six replicates. Treatment consisted of a corn-based growing-finishing diet containing 0% or 2.5% of PSH, where PSH replaced 0 or 3.8% of corn (DM basis). Lambs were allowed ad libitum access to their experimental diets. Drinking water was available at all times. Following the performance trial, the slaughter was carried out according to the “Bioethical code and Regulations of Animal Welfare” of the Facultad de Zootecnia y Ecología, Universidad Autónoma de Chihuahua. These guidelines are based on the Official Mexican Regulations for slaughtering domestic and wild animals (NOM-033-SAG/ZOO-2014). Converting muscle to meat was carried out for 48 h at 4°C. The carcasses were identified and cut, the left half carcass at a level to the 13 ribs was used for sampling. Afterward, loins were obtained from each carcass and evaluated at d 0 and d 7 shelf life (4 °C). Data were analyzed using the GLM procedure of SAS. Treatments were not statistically significant (P >0.10) on pH, water holding capacity (WHC), and shear force (SF), except for color and cooking loss. The pH, WHC, and SF averaged 5.81, 64.5%, and 5.22 N, respectively. Control lambs increase in lightness (P< 0.01) than those supplemented with PSH. In lambs has been associated with higher polyunsaturated fats content in meat, which might come from PSH´s shattered pecan kernel content escaping rumen hydrogenation. Cooking loss was greater (P< 0.05) in PSH lambs, which is associated with juiciness and tenderness in meat. Regarding evaluation of shelf life, color remained unchanged (P >0.10) but consistently reduced pH (P< 0.01) and increased (P< 0.01) WHC and SF. In conclusion, 2.5% of dietary pecan shell supplementation into growing-finishing diets does not affect the product image but seems to improve meat juiciness.