Choline forms for supplement manufacturing

How the forms compare

There is no single best form of choline for every supplement. The right choice depends on the label claim, the product format and the regulatory route in each target market. Choline bitartrate is the form SoleChem supplies, with the specification sheet and certificate of analysis sent with each quote. It is a 1:1 salt of the choline cation with hydrogen L-tartrate, molar mass 253.25 g/mol.

The table places choline bitartrate beside other choline sources that formulators often weigh. Only choline bitartrate is covered by this page’s technical data.

The main difference in a formulation is how much powder carries a given amount of choline. In choline bitartrate the tartrate counter-ion is heavy, so a large share of each gram is not choline. High label claims therefore need a large fill weight or several units per serving.

To calculate the powder needed, divide the declared choline amount by the choline fraction of the salt. The fraction is the molar mass of the choline cation (C5H14NO) divided by 253.25 g/mol, then corrected for the assay on the certificate of analysis. The elemental content calculator runs this arithmetic, and the overage calculator adds any stability overage.

Physical form matters as much as content. Choline bitartrate is a white crystalline powder that handles as a dry solid. Phosphatidylcholine is a lipid and suits oil-based fills, while choline chloride is easier to use in liquids than in dry blends.

Choosing a form

• Label claim per unit. Check the calculated choline bitartrate mass against the fill volume of the capsule size or the target tablet mass. The capsules and tablets guides cover these limits.
• Format. Choline bitartrate is a common choice in multivitamin tablets, capsules and powders. It is not oil-soluble, so in a softgel it would have to be suspended; a lipid source such as phosphatidylcholine fits that format more naturally.
• Moisture. Choline salts take up water from the air. Process in low-humidity rooms, use moisture-barrier packaging and consider a flow aid such as silicon dioxide. Hygroscopic fills can draw water from gelatin shells, so HPMC shells are worth testing.
• Odour and taste. Choline salts can develop a fishy, amine-like odour as trace trimethylamine forms during degradation. Include an odour check in stability testing. The tartrate gives a sour note in drink powders, which acidic flavour systems can accommodate.
• Cost per milligram of choline. Choline bitartrate is generally among the lower-cost choline sources per milligram of choline. Citicoline and alpha-GPC usually cost more per milligram.
• Regulatory route. Choline is regulated nationally in food supplements, so confirm acceptance of the exact form in each market before fixing the formula.

EU regulatory status

Choline is not among the vitamins and minerals listed in Annex I of Directive 2002/46/EC. Its forms, including choline bitartrate, therefore do not appear in Annex II of that Directive. The permitted forms guide explains how those annexes work.

The Directive still applies to food supplements that contain choline, because its definition covers other substances with a nutritional or physiological effect. Its labelling rules require the amount of such substances to be declared per daily portion. The labelling guide covers the full set of requirements, together with Regulation (EU) No 1169/2011.

The use of choline as an “other substance” is governed by national rules, which differ between member states. Some states operate positive lists or notification procedures, and any maximum amounts are set nationally. The maximum levels guide explains how to find each competent authority’s rules. Regulation (EC) No 1925/2006 provides a Union procedure to restrict other substances; check its Annex III for current entries.

Novel-food status depends on the exact form. Before using an alternative choline source, check the Union list in Implementing Regulation (EU) 2017/2470 under Regulation (EU) 2015/2283. The novel food guide describes the consultation process.

Any claim on the label must comply with Regulation (EC) No 1924/2006. Check the exact authorised wording and conditions in the EU Register of nutrition and health claims and the health claims guide.