What citric acid is
Citric acid is a hydroxy acid abundant in citrus fruit, but commercial material is produced by fermentation of carbohydrate feedstock using Aspergillus niger. Fermentation-derived product dominates the market; citrus extraction is not the commercial route.
It is used as an acidulant, pH regulator, chelating agent and antioxidant synergist. The application range is unusually wide — beverages, confectionery, prepared foods and supplements — and it handles well across dosage forms. FONTIA supplies citric acid (anhydrous).
Anhydrous vs. monohydrate — decide this first
Two forms circulate: anhydrous and monohydrate (crystalline). Chemically the same acid, but the water of hydration changes practical handling.
- Anhydrous — low moisture, suited to dry blending, tableting and powder systems. Needs attention to humidity during handling
- Monohydrate — carries one molecule of water. Stable in dissolution, used where the material goes into solution anyway
The point most often missed is active acid conversion. Roughly 8.6% of the monohydrate’s molecular weight is water, so the same charge weight delivers a different amount of acid. When switching between forms, recalculate the inclusion rather than carrying the old figure across — otherwise pH and taste shift.
Two regulatory regimes at once
Citric acid is both a designated food additive and a designated feed additive in Japan. In the FONTIA catalogue it sits under both food additives and feed additives.
Two lots can both read “citric acid, 99.5% min” and sit under different laws — food sanitation law versus the Feed Safety Act — with different compendial standards, documentation and expectations of the manufacturing site.
State whether the finished product is for humans or animals when requesting a quotation. Without it you may receive a specification that cannot be used, and discover the mismatch only after sample evaluation.
What to check on the specification
- Assay — compendial compliance, and whether stated on anhydrous or as-is basis
- Loss on drying — the measured value that distinguishes anhydrous from monohydrate
- Heavy metals, lead, arsenic — compendial or in-house standard
- Oxalate and readily carbonisable substances — purity tests defined in the compendium
- Particle size — governs dissolution rate and powder flow; fine and granular grades differ
- Production route — fermentation feedstock (corn etc.) bears on allergen and non-GMO documentation
Sourcing notes
Citric acid is a high-volume imported commodity, and specification non-conformities have been recorded at Japanese import inspection. Commodities invite the assumption that any source is equivalent; impurity profile and particle size in fact vary by manufacturing site.
- Country of origin and plant — qualify at site level, not just supplier level
- Per-lot CoA — confirm availability and format even for a commodity
- Packaging — 25 kg paper sacks are standard; plan storage and post-opening humidity control
- Price movement — tracks carbohydrate feedstock and energy costs; sharing annual volume early helps
FONTIA supplies from prototype-scale lots upward. For specifications, samples or a quotation see the citric acid product page or use the contact form. Related: fermentation-derived ingredients.