Meat quality is an important economic trait in livestock, with meat color being the main factor that governs consumers' buying decisions. Meat color is susceptible to oxidative stress and lipid peroxidation. Hence, antioxidants as functional feed additives have been applied in animal husbandry to increase the marketable value of meat. Cysteamine, a metabolite in animals, is used as a novel feed additive in animal production in the form of coated cysteamine hydrochloride (CC) because of its growth-promoting and antioxidant activities. It was hypothesized that the improved meat quality of cysteamine by increasing GSH levels and antioxidase activity could protect muscles against oxidative stress and lipid peroxidation. Therefore, the aim of the present study was to examine whether coated cysteamine improved growth performance and meat quality through delaying the oxidation of heme pigment and fatty acids in muscles of finishing pigs. For that purpose, a total of 288 crossbred finishing pigs (Duroc × Landrace × Yorkshire) with an initial BW of 88.3 ± 0.3 kg were randomly allotted into four dietary groups, with eight pens per group and nine pigs per pen. Pigs were fed a corn–soybean meal diet containing 0 (control), 0.035, 0.070, or 0.140 g/kg of CC for 29 days. At the end of experiment, one pig was randomly selected from each pen and samples of the longissimus dorsi muscle were collected and stored at 4 °C for assessment of meat quality.
As a result, dietary CC supplementation increased the a* and H* values and reduced the L* value in the longissimus dorsi muscles at 48 h postmortem. The deoxymyoglobin content was enhanced and the metmyoglobin and malondialdehyde contents were reduced in pigs fed the dietary CC. Pigs fed a dietary CC of 0.035 g/kg had a lower cooking loss and a higher a* (24 h) value in the longissimus dorsi muscles than pigs on control treatment. Dietary supplementation with CC had a significant effect on meat color that was observed 48 h after slaughter. A 0.035 g/kg dosage proved to be the optimal dosage of CC that improves meat quality, especially by preserving the meat color after long chill storage, through improving antioxidative ability and slowing down lipid oxidation.
Bai, M., Liu, H., Xu, K., Zou, B., Yu, R., Liu, Y., Xing, W., Du, H., Li, Y., & Yin, Y. (2018). Effects of dietary coated cysteamine hydrochloride on pork color in finishing pigs. Journal of the Science of Food and Agriculture, 98(5), 1743-1750. https://doi.org/10.1002/jsfa.8647