How to Read a Certificate of Analysis for Dehydrated Ingredients
A Certificate of Analysis (COA) is the primary quality verification document in B2B ingredient sourcing. It should tell you everything you need to know about a batch of ingredients before you accept it. But a COA is only useful if you know how to read it — and many procurement teams are not fully equipped to distinguish a well-constructed COA from one that is vague, incomplete, or potentially fabricated. This guide walks through every section in detail.
What a COA Is and Why It Matters
A Certificate of Analysis is a document issued by a supplier or an accredited third-party laboratory that summarises the analytical test results for a specific batch of product. It confirms that the batch has been tested against defined specifications and records the actual measured values for each parameter.
For dehydrated food ingredients, the COA is the document that bridges the gap between what a supplier claims about their product and what was independently verified for the specific batch you are receiving. In the absence of a COA — or with a COA that is poorly constructed — you have no meaningful quality assurance. Every batch should come with its own COA. Generic or undated COAs are not acceptable in professional ingredient sourcing.
Section 1: Product Identification
The header section of a COA establishes the identity of the product and the batch. Every COA must include the following, and you should verify each one:
| Field | What to Check | Red Flag |
|---|---|---|
| Product Name | Must match exactly what you ordered — including specification (e.g., "Onion Powder 80 mesh") | Generic name without specification |
| Batch / Lot Number | Unique identifier linking the COA to a specific production run | Missing, or same number used repeatedly |
| Date of Manufacture | Should be recent; verify against best before date for shelf life | Missing date or implausible shelf life |
| Best Before Date | Typical shelf life for dehydrated veg is 18–24 months from manufacture | Best before date already passed |
| Country of Origin | Must declare origin of the raw material, not just where it was packed | Vague — "India / Imported" without specifics |
Section 2: Physical Parameters
Physical parameters describe the sensory and structural characteristics of the ingredient. These are the first indicators of quality and consistency.
- Moisture content: This is the single most critical physical parameter for dehydrated ingredients. Most dehydrated vegetables should be at or below 7% moisture. High-value or sensitive products — such as garlic powder or moringa — should be at 5% or below. Higher moisture content shortens shelf life, promotes microbial growth, and causes caking.
- Colour (CIE L*a*b* or visual descriptor): CIE L*a*b* values provide an objective, measurable colour standard. A visual descriptor alone ("greenish-yellow powder") is acceptable as a supplementary description but not as a standalone specification. If colour is important to your formulation, request L*a*b* values and compare them against your approved sample.
- Particle size (mesh): Expressed as a percentage passing through a defined mesh screen — e.g., "95% passing through 80 mesh." This is critical for formulation consistency, particularly in spice blends, coating powders, and reconstitutable products.
- Bulk density: Expressed in g/100ml or g/cm³. Relevant for packaging fill weights, dosing system calibration, and shelf space calculations. Significant batch-to-batch variation in bulk density may indicate inconsistent milling or moisture variation.
- Appearance / Foreign matter: Should confirm absence of visible foreign matter, insect damage, and extraneous material. This is a basic food safety checkpoint.
Section 3: Chemical and Nutritional Parameters
Chemical parameters establish the compositional integrity of the ingredient. For dehydrated vegetables and spices, the key values to scrutinise are:
- Total ash content: Ash represents the inorganic mineral content of the product. Elevated ash content can indicate contamination with soil or mineral adulterants. Typical values for dehydrated vegetables range from 3–8% depending on the product.
- Acid Insoluble Ash (AIA): This is arguably the most important adulteration indicator in a COA. AIA measures the ash that does not dissolve in acid — primarily silica from sand and soil particles. A high AIA value strongly suggests the product has been adulterated with sand, dirt, or mineral filler. Acceptable AIA for most dehydrated vegetables is below 1%. Values above 1.5% should trigger a rejection.
- Volatile oil content (spices): For products such as turmeric, cumin, coriander, or chilli, volatile oil or curcumin content is the primary quality indicator. Low values indicate old stock, poor raw material quality, or adulteration with spent spice material.
- Protein, carbohydrates, and fat: These values should align with published nutritional databases for the specific ingredient. Significant deviations may indicate adulteration or abnormal raw material.
Section 4: Microbiological Parameters
Microbiological testing is non-negotiable for food-grade ingredients. Every COA for dehydrated food ingredients should include results for the following parameters, with acceptable limits as noted:
| Parameter | Acceptable Limit (typical) | Notes |
|---|---|---|
| Total Plate Count (TPC) | < 100,000 CFU/g | Lower limits required for high-risk applications |
| Yeast & Mould | < 1,000 CFU/g | Elevated values suggest moisture control failure |
| E. coli | Absent in 1g | Presence indicates faecal contamination — reject batch |
| Salmonella spp. | Absent in 25g | Mandatory; absence must be confirmed by method reference |
| Staphylococcus aureus | < 100 CFU/g | Relevant for ready-to-eat or minimally processed applications |
Section 5: Pesticide Residues
Pesticide residue testing is increasingly expected by retailers, certification bodies, and regulators in export markets. The EU maintains the most comprehensive and stringent Maximum Residue Limit (MRL) database in the world, covering several hundred active substances across all food categories. For ingredients destined for the EU market, EU MRL compliance is the gold standard and should be specified in your purchase contract.
Not all COAs will include a full pesticide panel. You should specify the panel required — multi-residue screening covering 200+ active substances is now standard practice for reputable suppliers. If a COA only references a handful of pesticides, ask why and request the full panel. A supplier that resists this request warrants careful scrutiny.
Section 6: Heavy Metals
Heavy metal limits vary by market and product category. The four primary metals to check are Lead (Pb), Cadmium (Cd), Arsenic (As), and Mercury (Hg). EU Regulation (EC) No 1881/2006 and its amendments set limits for specific food categories — and these are frequently updated. Baby food and infant formula categories carry significantly stricter limits than general food ingredients.
For spices and herbs in the EU, cadmium and lead limits have been progressively tightened. If you are sourcing for retail or branded products, confirm that your supplier tests to the most current applicable limits — not limits that were valid two or three years ago.
Red Flags: When to Reject a COA
- ✗No batch number or generic batch reference — a COA without a unique, traceable batch number is almost certainly a template document, not a genuine batch analysis.
- ✗No laboratory name or accreditation number — results without an identified, accredited testing laboratory cannot be verified and should not be trusted.
- ✗Suspiciously perfect results — if every single value lands exactly at the specified limit (e.g., moisture exactly 7.00%, TPC exactly 100,000), the results may have been manually adjusted to appear compliant.
- ✗Rounded moisture values — actual laboratory measurements produce decimal values (e.g., 5.43%). A moisture reported as exactly 7.00% suggests estimation rather than measurement.
- ✗No microbiological testing — omission of micro testing is not acceptable for food-grade ingredients. If a supplier provides a COA with only physical and chemical parameters, insist on micro results before accepting stock.
- ✗COA older than the shipment — a COA dated prior to the claimed production date is incoherent. COAs should post-date or align with production.
How to Verify a COA is Genuine
A legitimate COA from a reputable supplier can be cross-verified through several channels:
- NABL accreditation number: In India, the National Accreditation Board for Testing and Calibration Laboratories (NABL) is the primary accreditation body for food testing laboratories. Every NABL-accredited lab is assigned a unique certificate number which can be verified at nabl.gov.in. This is the first verification step for any COA from an Indian supplier.
- Lab website cross-check: Confirm the laboratory named on the COA exists, is operational, and is accredited for the parameters listed. Fictitious lab names are a known fraud vector in commodity ingredient supply chains.
- Request the raw lab report: A supplier's COA is a formatted summary. For high-value orders or new supplier qualification, request the original laboratory report with the lab's letterhead, analyst signature, and method references. Any resistance to providing this warrants caution.
What Atlas AgroFood Provides
Every batch shipped by Atlas AgroFood is accompanied by a NABL-accredited COA covering physical, chemical, microbiological, and — where specified — pesticide residue parameters. Our COAs are batch-specific, dated, and verifiable. We do not issue generic template COAs, and we welcome third-party verification requests. Contact us to discuss your documentation requirements before your first order.
Get Full Documentation With Every Shipment
Atlas AgroFood provides NABL-accredited Certificates of Analysis with every batch, covering all parameters relevant to your market. Speak to our team to discuss your specific documentation and compliance requirements.