What is L-lysine HCl 98.5%?
L-lysine HCl is the hydrochloride salt of L-lysine, produced by bacterial fermentation followed by purification and crystallisation. The "98.5%" on the label refers to the content of L-lysine monohydrochloride, not of lysine itself. For the biology of lysine and its role as the first limiting amino acid in pig diets, see our general page on lysine.
Because the hydrochloride part of the molecule carries no lysine, the lysine value used in formulation is lower than the purity figure. This distinction is the most common source of errors when lysine products are compared or substituted.
Composition: where the 78.8% comes from
Pure L-lysine monohydrochloride contains about 80% L-lysine by weight; the rest is hydrogen chloride. A product guaranteed at 98.5% therefore supplies about 0.985 × 80% ≈ 78.8% L-lysine. Most nutritionists enter feed-grade lysine HCl in their matrix at around 78–79% lysine, but the value should always be checked against the supplier's specification and certificate of analysis.
The chloride carried by the salt is also nutritionally relevant: pure lysine HCl contains roughly 19% chloride. At normal inclusion levels this is a small contribution, but in high-inclusion, low-protein diets it is worth accounting for in the electrolyte balance.
Typical specification items
- Assay: L-lysine monohydrochloride ≥98.5% on the stated basis (as is or dry matter, depending on the supplier).
- Moisture or loss on drying: low, as stated in the specification.
- Ash / residue on ignition, ammonium salts and heavy metals within the supplier's and local regulatory limits.
- Specific rotation, which confirms the L-isomer.
- Particle size and bulk density, relevant to mixing and dosing accuracy.
- Certificate of analysis (CoA) and lot number on every delivery.
Handling and storage
Lysine HCl is somewhat hygroscopic. In humid conditions it can pick up moisture and form lumps, which impairs flow through bins and micro-dosing systems. It should be stored in closed, original bags in a cool, dry place, off the floor, and used on a first-in, first-out basis. Opened bags should be resealed.
Granulated or low-dust grades are available from some producers and can flow better in automated systems; the lysine content of such grades must be taken from their own specification.
Converting between lysine products
All lysine products should be compared and substituted on an L-lysine basis, not on product weight. The amount of a replacement product is the lysine to be supplied divided by its lysine content.
Example: 1 kg of lysine HCl at 78.8% lysine supplies 0.788 kg L-lysine. To supply the same amount from a lysine sulphate product with 55% lysine you need about 0.788 ÷ 0.55 ≈ 1.43 kg. When switching, the extra product mass, its other nutrients and its different chloride or sulphate contribution should be reflected in the formula.
Lysine HCl compared with other grades
- Lysine HCl 98.5%: highest lysine concentration of the dry forms, high purity, a widely traded commodity; adds chloride.
- Lysine sulphate: lower lysine content (around 55%) with other fermentation solids that also contribute some energy and other amino acids; adds sulphate instead of chloride.
- Liquid lysine: dosed through liquid systems at larger feed mills; content per kg as specified by the producer.
- The choice usually comes down to price per kg of lysine delivered, the mill's dosing equipment and the overall mineral balance of the diet.
CTF Premix and L-lysine HCl
L-lysine HCl can be included in CTF Premix's vitamin, mineral and custom premixes according to the customer's formulation, calculated on an L-lysine basis together with other amino acids, vitamins and trace minerals. Our premixes are produced at our Ankara facility under ISO 9001:2015 and GMP, and every lot has a certificate of analysis and full lot traceability.
This page is for general information. Inclusion rates and product choice should be decided with a nutritionist, taking into account the species, the feed formulation and the applicable regulations.