Buyer Guides
How to Choose the Right Psyllium Husk Grade and Mesh
TL;DR. Psyllium husk is selected on three axes: purity grade (85-99%), mesh size (40-200), and certification (organic / conventional). Pharmaceutical and capsule formulations need 99% purity at mesh 80-100. Bulk fibre supplements work at 85-95% purity. Bakery applications use coarser 40-60 mesh. This guide explains how to specify each axis without over-paying or under-spec’ing.
1. Purity grade: the soluble-fibre yield
“Purity” in psyllium husk is measured by swell volume, the millilitres of gel formed by 1 gram of husk in water (USP method). The higher the swell volume, the more soluble fibre per kilogram of raw material.
| Purity Grade | Swell Volume (ml/g) | Typical Use |
|---|---|---|
| 85% | ≥ 28 | Animal feed, low-cost supplements |
| 90% | ≥ 32 | General fibre powders, bakery |
| 95% | ≥ 36 | Mid-tier supplements, beverage premixes |
| 98% | ≥ 38 | Premium supplements, capsule fill |
| 99% (Pharma) | ≥ 40 | USP / EP / IP pharmaceutical grade, OTC laxatives |
If your buyer’s audit will reference USP <785> or the EP psyllium monograph, you must spec 99% purity. Anything below will fail USP swell-volume testing.
2. Mesh size: particle size for downstream process
Mesh number is the count of openings per linear inch of sieve. Higher mesh = finer powder.
| Mesh | Particle Size | Best For |
|---|---|---|
| 40 | ~420 µm | Whole-flake fibre, retail psyllium husk packs |
| 60 | ~250 µm | Capsule fill (good flow rate) |
| 80 | ~177 µm | Tablet binding, gluten-free flour blends |
| 100 | ~149 µm | Beverage stick packs, premium capsule fill |
| 200 | ~74 µm | Pharmaceutical orodispersibles, smooth-mouthfeel beverages |
Coarser flakes (40-60 mesh) hydrate slowly and give “textural integrity”, important in baked goods. Finer powders (100-200) hydrate fast and form smoother gels, preferred for instant beverages and clinical-grade laxatives.
3. Certification: organic vs conventional
Conventional psyllium husk and certified organic USDA / EU / NPOP organic share the same physical and microbial spec. The differences are:
- Pesticide-residue panel: organic must demonstrate non-detect for prohibited substances (LC-MS/MS & GC-MS/MS). Conventional has standard residue limits.
- Documentation: organic ships with a Transaction Certificate per shipment from the certifier; conventional does not.
- Price: organic typically commands a 12-25% premium over conventional, depending on grade and harvest year.
If your end-product carries an organic seal (USDA / EU / India NPOP) you must source organic. If it doesn’t, conventional is usually the better economics.
4. Microbial & heavy-metal limits
For supplement and pharma applications, the typical spec ceiling is:
- Total Plate Count: < 10,000 CFU/g
- Yeast & Mould: < 100 CFU/g
- E. coli, Salmonella: absent in 25 g
- Heavy Metals (Lead): < 3 ppm (ICP-MS)
- Aflatoxins: < 4 ppb B1 / < 10 ppb total (HPLC)
Ask your supplier for the microbial test method (ISO 4833 for TPC, ISO 16649 for E. coli, ISO 6579 for Salmonella), this signals lab maturity.
5. What to ask for upfront
Before committing to a supplier, request:
- COA with the exact purity, mesh, swell volume and microbial limits for the lot.
- Sample (1-5 kg) for in-house QC and formulation pilot.
- Pricing matrix for the grade × mesh × pack-size combination on FOB and CIF terms.
- Documentation pack: COO, Phytosanitary Certificate, third-party microbial / heavy-metal report, and Transaction Certificate (if organic).
- Lead time and MOQ at sample, 1 MT, 5 MT, and full-container scale.
Frequently asked questions
What is the difference between psyllium husk and psyllium husk powder?
Psyllium husk is the unmilled outer seed coat (40-60 mesh, flake-form). Psyllium husk powder is the same material milled finer (80-200 mesh) for capsule, tablet, beverage and bakery use. Both are Plantago ovata.
Do I need 99% purity for a generic fibre supplement?
No. 95% or 98% delivers identical functional fibre per serving for retail supplements at lower cost. Spec 99% only when your formulation must comply with USP, EP, or other pharmacopoeial monographs.
Which mesh size for a capsule fill?
Mesh 60-80 for size-0 to size-00 capsules. Finer than 100 mesh tends to bridge in capsule fillers; coarser than 60 underfills capsules and reduces dose accuracy.
Can I switch between conventional and organic mid-contract?
Yes, technically, both grades are processed on the same equipment at certified facilities. But a switch invalidates your existing organic Transaction Certificate; new lots will need fresh TCs.
Need help mapping your formulation to the right grade and mesh? Send our export desk an RFQ. We respond with sample, COA and quote within 24 business hours.