How to Read a Sucralose Certificate of Analysis (COA)

A Certificate of Analysis (COA) is the lab report that tells you what is actually in a batch of sucralose — not what the marketing says, but what an accredited laboratory measured. Most sellers keep COAs "available on request" or don't publish them at all. We publish the full panel for every batch, by lot number, at our COA lookup. This guide walks through what each line means so you can read one with confidence.

The header: batch identity and lab credentials

Before any results, a trustworthy COA establishes who tested what:

• Lot / batch number — the traceable code (ours look like TSC-26001) printed on the label and matching the published COA. This is what makes a claim verifiable: you can look up the exact batch you received.
• Lab name and accreditation — the testing laboratory and its accreditation, ideally ISO/IEC 17025 (often with an A2LA registration number). Accreditation means the lab's methods and competence are independently audited. A result from an unaccredited or in-house-only lab carries less weight.
• Sample received / test completed dates — when the lab handled the sample, establishing the report is tied to a real, dated event.

If a "COA" has no lot number, no named accredited lab, and no dates, treat it as marketing, not evidence.

The panel: analyte by analyte

The heart of the COA is a table where each row lists an analyte, the test method, the specification (the allowed range or limit), the result (what was measured), and pass/fail. Here's what the key rows mean for sucralose.

Assay / purity

• What it is: the percentage of the sample that is actually sucralose, on a dried basis.
• Typical spec: high-purity food-grade and pharmacopeia standards generally require roughly 98.0–102.0% (the >100% figures come from the calculation against a reference standard).
• How to read it: a result comfortably inside that window means you're getting single-ingredient, high-purity sucralose — not a diluted or filler-laden product. This is the number that makes accurate dosing possible.

Appearance and identification

• Appearance: typically "white to off-white crystalline powder," free of foreign matter.
• Identification (e.g., IR spectroscopy): confirms the molecule is sucralose — a fingerprint match against a reference. Prevents mislabeling or substitution.

Specific optical rotation

• What it is: sucralose is a chiral molecule that rotates polarized light by a characteristic amount. Measuring specific rotation confirms both identity and stereochemical integrity.
• How to read it: a result within the specified range is another independent confirmation you have genuine sucralose.

Water / loss on drying

• What it is: moisture content (Karl Fischer titration) or loss on drying.
• Why it matters: excess moisture can affect stability, caking, and the accuracy of the assay. Low, in-spec moisture supports the long shelf life of the dry powder.

Heavy metals

• What they are: trace contaminants — commonly lead, arsenic, cadmium, and mercury, each with a strict maximum (reported as a limit like "≤ X ppm" or "≤ X mg/kg").
• How to read it: every result should be at or below the limit (often "< detection"). These matter because an ingredient you consume regularly should carry negligible heavy-metal load.

Microbial limits

• What they are: counts and pathogen screens — total aerobic plate count (TPC), yeast and mold, and pathogen tests such as E. coli, Salmonella, and Staph. aureus.
• How to read it: counts should be within specified maximums and pathogens absent / negative. This is basic food-safety hygiene of the batch.

Related impurities — including sucralose-6-acetate (S6A)

• What it is: manufacturing-related substances that can accompany sucralose. The one that generates the most questions is sucralose-6-acetate (S6A) — the impurity/metabolite at the center of a 2023 in-vitro genotoxicity study we discuss in our safety evidence review.
• The transparency point: S6A is not always on a standard panel, and many sellers don't report it. We report the S6A result on every batch precisely because it's the concern people raise — so an anxious question becomes a number you can read, compared against a defined specification.

How to use a COA when you shop

1. Match the lot. Confirm the COA's lot number matches the batch you received or intend to buy.
2. Check the lab. Look for an accredited third-party lab (ISO/IEC 17025), not "tested in-house."
3. Read assay first. Confirm high purity (~98–102%) — that's your single-ingredient guarantee.
4. Scan the safety rows. Heavy metals at/under limit, microbials in spec and pathogens negative.
5. Find S6A. If the impurity everyone argues about is reported and within spec, the biggest fear is answered with data.

Red flags that a "COA" isn't really one

Not every document labeled "Certificate of Analysis" deserves the name. Be skeptical when you see:

• No lot number, so nothing ties the report to the product in your hand.
• A specification-only sheet ("meets the following specifications") with no measured results — that's a spec sheet, not a test report. A real COA shows the actual numbers found.
• No named lab or accreditation, or "tested in-house" with no third-party verification.
• Undated, or reused across every batch indefinitely — results should be tied to a specific dated sample.
• A generic PDF that never changes batch to batch, which suggests it's marketing collateral rather than per-lot testing.
• Only "available on request," which in practice often means a single old document, if it arrives at all.

The gold standard is the opposite of all of these: a dated, lot-specific, accredited-lab report with measured results, published where anyone can pull it up by batch.

COA vs spec sheet vs "third-party tested"

These phrases are often used loosely, so it helps to separate them. A specification sheet states the targets a product is supposed to meet. The claim "third-party tested" on a label tells you testing happened somewhere but shows you nothing. A Certificate of Analysis is the actual measured result for a specific batch — the only one of the three you can independently verify. When a seller offers all three, the COA is the document that matters, and a published, per-lot COA is the strongest form of it.

Why we publish every batch

The sweetener industry's norm is COA-on-request, or no COA at all. Our model is the opposite: proactive, public, per-batch, full-panel COAs — including S6A — searchable by lot at /coa. It's the most direct answer to "what's really in it?": not a claim, a lab report you can read yourself. Browse our sucralose products and pull up the COA for the exact batch before you buy.