L-methionine

L-Methionine (CAS 63-68-3), commonly abbreviated as Met, is an essential sulfur-containing amino acid that the human body cannot synthesize and must obtain through diet or supplementation. In industry, it functions as a nutritional fortifier, antioxidant stabilizer, and precursor compound across food, pharmaceutical, feed, and personal care manufacturing sectors worldwide.

In animal nutrition, it is added to poultry, swine, and aquaculture feeds to correct methionine deficiency and improve feed conversion ratios, representing one of the highest-volume applications globally. Pharmaceutical manufacturers use it as an active ingredient in amino acid infusion solutions and tablet formulations targeting liver support and metabolic health for various patient populations.

Food producers incorporate it to fortify protein supplements, clinical nutrition products, and functional foods where amino acid completeness is a specific labeling requirement for the end consumer. In personal care, it acts as a humectant and antioxidant in skin and hair formulations, helping protect product stability and support moisture retention claims in high-end cosmetic lines.

L-Methionine is supplied as a white crystalline powder or free-flowing granules. Standard grades include USP, BP, Ph. Eur., and food-grade (FCC), with feed-grade material also broadly available. Packaging typically ranges from kilogram quantities up to bulk metric-ton bags to accommodate both specialty formulators and large-scale feed producers requiring consistent supply chains.