Taste and odour masking
The problem
Sensory failure is the one formulation problem the consumer detects immediately and reports loudly. A bitter mineral, a metallic iron note, the sulphur of NAC or the fishy odour that develops on choline bitartrate will end a product regardless of how good the rest of the formulation is.
It also caps the dose. Formulators routinely reduce an active below its intended level purely because the sensory profile at the target dose is unacceptable — which means the sensory problem has quietly become an efficacy problem.
Why the conventional ingredient fails
Flavour systems mask by competing with the off-note, which works up to a threshold and then stops. Above it, adding flavour simply produces a strong unpleasant taste instead of a weak one. Bitterness from potassium chloride and caffeine, the metallic character of iron salts, and the sulphurous volatiles of NAC are not reachable by flavour alone at high loadings.
How NexaGens addresses it
A physical barrier, not a competing flavour. The requirement is precise: the barrier must stay intact in saliva for the seconds to minutes the material is in the mouth, then dissolve in the stomach so the active is fully available. That is a sensory barrier, not a release-modifying one — the product remains immediate release.
For odour rather than taste, the barrier must additionally retain volatiles during storage, which is a different and often harder requirement.
Relevant products
| Product | Assay | Masks | Status |
|---|---|---|---|
| Potassium Chloride Taste-Masked IR Pellets | 85% w/w | Bitterness, metallic taste | Qualified |
| Iron Bisglycinate Taste-Masked IR Pellets | 75% w/w | Metallic taste + interaction protection | Qualified |
| N-Acetyl-L-Cysteine Taste- and Odour-Masked IR Pellets | 85% w/w | Sulphurous taste and odour | Qualified |
| Choline Bitartrate Taste- and Odour-Masked IR Pellets | 50% w/w | Taste, fishy odour, moisture | Qualified |
| Microencapsulated Caffeine (Immediate Release) | On qualification | Bitterness | Qualified |
| Microencapsulated Ferrous Bisglycinate | On qualification | Metallic taste | Qualified |
| Microencapsulated Ferric Pyrophosphate | On qualification | Metallic taste, colour impact | Qualified |
What to specify, and how to test it
Taste masking is the area where unverifiable claims are most common, because sensory work is expensive and easy to skip. Ask for:
- A two-stage dissolution result. Not more than a stated percentage released in simulated saliva at 2 minutes, and not less than a stated percentage released in gastric medium within 60 minutes. One without the other is meaningless: a barrier that never dissolves masks perfectly and delivers nothing.
- The simulated saliva composition and pH used, and the time point. These are not standardised across suppliers.
- A sensory panel design — panel size, training status, whether the test is triangle or ranking, and the acceptance criterion. “Panel confirmed” is not a result.
- Dose at which masking was demonstrated. Masking at 100 mg says nothing about 500 mg.
- The matrix it was demonstrated in. Sensory performance in water does not transfer to a fruit-flavoured stick pack.
- For odour: headspace volatile analysis over storage, not just a panel at release.
Next steps
See the taste-masked pellets · Discuss a taste-masking project