Excipients & Processing Aids

What manufacturers buy here

This category covers excipients and processing aids: the non-nutritive materials that turn actives into a capsule, tablet, gummy or powder. Formulators usually group them by the job they do rather than by chemistry.

• Capsule shell materials: gelatin, HPMC (hypromellose) and pullulan. See ingredients for capsules and ingredients for softgels.
• Fill and compression aids: microcrystalline cellulose as filler-binder, magnesium stearate as lubricant, and silicon dioxide as glidant and anti-caking agent. See ingredients for tablets.
• Gelling agents, bulking agents and sweeteners: pectin, polydextrose and the polyols erythritol, mannitol and sorbitol, used in gummies and chewable tablets.
• Acidulants and buffers: citric acid and trisodium citrate, used in effervescent tablets and powders.

Choosing within the category

Shell origin. Gelatin is of animal origin. HPMC and pullulan are not, which matters for products positioned for vegetarian consumers. HPMC shells also hold less water than gelatin shells, which suits hygroscopic fills.

Process route. Direct compression needs a compactible filler such as microcrystalline cellulose, plus a lubricant and a glidant. Magnesium stearate is hydrophobic, and overmixing can slow tablet disintegration. Sodium stearyl fumarate, the usual less hydrophobic alternative in pharmaceuticals, is not an authorised food additive under Annex II of Regulation (EC) No 1333/2008, so it cannot be used as a lubricant in food supplements.

Moisture behaviour. Sorbitol is hygroscopic, while mannitol is not, so mannitol is the common polyol for moisture-sensitive chewables. Erythritol gives bulk with low hygroscopicity but has a cooling taste.

Specification. An excipient used as a food additive must meet the EU purity criteria for that additive, not only a pharmacopoeia grade. SoleChem sends the specification sheet and certificate of analysis with its quote; state the grade you need in the quote form.

Regulatory notes

Excipients that act as food additives in food supplements must be authorised for food category 17 in Annex II of Regulation (EC) No 1333/2008 and meet the specifications in Regulation (EU) No 231/2012. Conditions of use differ by additive and by supplement form, so check each one against the current consolidated text. Gelatin is regulated as a food ingredient, not as an additive. Additives are declared in the ingredient list by functional class and name or E number under Regulation (EU) No 1169/2011, and polyols above a set content trigger a mandatory statement under its Annex III.