Batch testing is what separates a controlled production environment from a flea market. Every batch (lot) of finished product must be tested against its written specifications before release. The output is a Certificate of Analysis (COA) tied to the batch number, archived alongside the Batch Production Record (BPR).
Standard batch release tests for supplements:
- Identity confirmation of finished product
- Potency of labeled active ingredient(s)
- Heavy metals (when applicable)
- Microbial counts (total aerobic, yeast/mold, pathogens by negative-result confirmation)
- Disintegration/dissolution (for tablets and capsules)
- Physical properties (weight variation, fill weight)
- Visual inspection (color, shape, capsule integrity)
21 CFR 111 (the FDA cGMP for dietary supplements) requires that every batch be tested for identity of components and that finished batches meet specifications before release. The standard reduction is "skip-lot" testing — after a manufacturer demonstrates statistical control across multiple batches, certain tests can be performed on a reduced frequency rather than every batch. Skip-lot reductions require documented justification.
For cosmetics under ISO 22716, batch testing focuses on microbial counts, preservation efficacy, physical properties (viscosity, pH, color), and packaging integrity. For food, batch testing covers microbial pathogens, allergen verification, and (for some categories) toxin screening.