Short answer: if you are comparing suppliers of Magnesium Citrate Capsules, compare certificates rather than descriptions. Active content per capsule and capsule weight are measurable, disintegration is measurable, and a supplier who cannot quote values for all three is quoting a catalogue, not a lot.
Magnesium Citrate Capsules is a capsule dosage form produced for industrial formulation rather than for retail sale. Production starts with raw material intake and lot identification, moves through the processing steps that define the material's character, and ends with a release decision against a retained reference standard. The reference is the part most buyers never see, and it is the part that decides whether month six behaves like month one.
Because the material is sold on specification, the useful question is not "what is it" but "what does the certificate say". A lot that meets a written range for active content per capsule and capsule weight is worth more than a lot that is merely described as premium, and the difference usually shows up in the filling line rather than in the sample bottle.
The parameters below are the ones that usually decide whether a trial succeeds. Values are typical release ranges; the certificate for a specific lot will quote measured results rather than the range.
| Parameter | Typical value | Method |
|---|---|---|
| Product | Magnesium Citrate Capsules | — |
| Category | Health Care Product | — |
| Appearance | Conforms to the retained reference | Visual |
| Active Content Per Capsule | Within the agreed release range | In-house / third party |
| Capsule Weight | Quoted on the certificate | In-house |
| Disintegration | Verified before release | In-house |
| Suggested dosage | As declared on the label in the finished dosage form | Application trial |
| Microbiology | Within food grade limits | ISO 4833 / ISO 21527 |
| Heavy metals | Below the destination market limit | ICP-MS |
| Packaging | 60 capsules per bottle, bulk in 25 kg cartons | — |
| Shelf life | 24 months unopened | Stability data |
Magnesium Citrate Capsules is used mainly in supplement brands, private label ranges and e-commerce. Each application stresses the material differently, so the same grade is rarely optimal everywhere.
Supplement Brands: in this system the material competes with everything else for the same sensory or functional space. A three point dosage curve — 0.7x, 1.0x and 1.3x of the suggested level — tells you more in one afternoon than three rounds of correspondence.
Private Label Ranges: the constraint here is usually label claims that the certificate cannot support. Start at the lower end of the suggested range, confirm the sensory or analytical result, and only then move up. Pushing the dosage to compensate for a weak raw material is the most common reason a formula becomes unstable later.
E-commerce: in this system the material competes with everything else for the same sensory or functional space. A three point dosage curve — 0.7x, 1.0x and 1.3x of the suggested level — tells you more in one afternoon than three rounds of correspondence.
The usual starting point is As declared on the label in the finished dosage form. Two adjustments are almost always needed: one for the process, and one for the market. A process that exposes the material to heat for longer than a few minutes will need a higher charge to deliver the same result at the end, and a market with a stricter labelling rule may cap what you can declare.
Rather than guess, ask for a sample and run the curve. A supplier who has supplied the application before can usually predict where the window sits, and that prediction is worth more than a lower price.
Release testing for this category typically covers active content, capsule weight variation, disintegration and microbiology. Microbiology is run on a schedule, and heavy metals or pesticide residue are tested either on a schedule or against the requirement of the destination market. The tests are not unusual; what distinguishes a reliable supplier is that the results are quoted, retained and traceable.
Retained samples are held for 24 months in most operations, which is what makes an investigation possible. Without a retained sample, a complaint six months later can only be answered with an opinion.
Standard packing is 60 capsules per bottle, bulk in 25 kg cartons. Trial quantities of 1 kg and 5 kg are normally available, and a production run follows once the specification is agreed in writing. Lead time is typically 7 to 15 working days ex-works, and mixed containers can be consolidated across categories to reach a full load.
The documents that matter at the border are the commercial invoice, packing list, certificate of origin where applicable, and the health or non-GMO declarations some destinations require. These are issued with the shipment rather than after it, because a container held at customs costs more per day than the material is worth per kilogram.
The same material can be a food ingredient in one market and a regulated substance in another, so the destination decides the paperwork. In the European Union the relevant framework is the food additive and flavour regulation set, with labelling driven by the allergen list. In the United States the equivalent conversation is about GRAS status and FDA labelling. In much of Asia the requirement is a health or food safety declaration issued at the border.
None of this changes what the material is. It changes what has to be written on the label and which certificate has to travel with the pallet, and it is worth settling before the artwork is printed.
Four variables move the price of Magnesium Citrate Capsules more than anything else: the specification range, the quantity of the run, the packing, and the documentation. A tighter assay is not a marketing claim, it is a yield loss at the plant, and it is priced accordingly. A 1 kg trial and a 25 kg drum are not the same product commercially even when the certificate is identical.
Beware of quotes that are much lower than the market: in this category they usually mean a wider specification, a substitute raw material, or a certificate written for a different lot. The cheapest way to find out is to buy a sample, test it against the specification, and compare the result with the certificate that came with it.
The recurring issue in this category is label claims that the certificate cannot support. It rarely appears in a sample and almost always appears in production, which is why trials should be run in the real matrix rather than in water.
What is the minimum order quantity for Magnesium Citrate Capsules? Typically 1 kg for a trial and 25 kg for a production order, though the packing can be adjusted for a first run.
Can you send a sample with its certificate? Yes. Samples of 100 g to 500 g are dispatched with the lot certificate, usually within three working days.
Is the specification negotiable? Within the production window, yes. A narrower assay, a different mesh or a declared allergen position can usually be accommodated, and the answer comes with a sample rather than a promise.
Which documents are supplied? COA for the lot, MSDS, allergen statement, non-GMO statement and packing list.
How is the material packed for export? 60 capsules per bottle, bulk in 25 kg cartons, with an inner food grade liner. Custom packing is possible from 100 kg.
How long does delivery take? 7 to 15 working days ex-works for a standard grade, longer where a custom specification or private label artwork is involved.
If you are specifying Magnesium Citrate Capsules for a new formulation, the fastest route to a decision is a sample with its certificate and a short conversation about the process it has to survive. Send the target values and the application, and the answer will come back with a specification and a lot number rather than a brochure.
