Quick answer. A garlic powder specification is not a list of ceilings. It is a set of lines that each answer a different question: what the product is, how it behaves in handling, what it must not carry, and how a lot gets verified. Read every line together with its method, its basis and its sampling plan. Do that and most specification disputes never start.
One reading rule before the numbers. A line only becomes a specification when it names the limit, the test method and edition, the reporting basis, the sampling plan, and the disposition for an out-of-window lot. Drop any one of the five and the line is a claim, not a specification. This guide reads a real garlic powder sheet against that rule.
Garlic powder appears on more specification sheets than almost any other dehydrated vegetable, and the sheets disagree with one another in ways that are rarely about quality. Two suppliers can both process Shandong garlic and ship a pale, free-flowing powder, then hand you documents that cannot be compared line for line: different standards behind the same column, different sieve language, different sulfite methods, different microbiology plans. The general Chinese spice standard these sheets borrow from was revised in 2026, and the new edition took effect on October 1, 2026, changing some of that language overnight.
This guide stays on one commodity on purpose. It walks through a garlic powder specification line by line, names the document standing behind each line, asks what the line actually guards in a plant, and finishes with the lines worth writing into a purchase contract when you switch suppliers. For the surrounding procurement process, the spice procurement guide covers standards, supplier qualification and batch continuity in full.
How to Read a Garlic Powder Specification in Four Groups
Before any single number, sort the sheet into four groups. Every line you will ever see belongs to one of them, and each group is answered by a different kind of document.
| Group | Question it answers | Lines you will see |
|---|---|---|
| Identity and composition | Is this garlic, in which commercial form, produced by which route? | Botanical name and form, product standard reference, extract or nitrogen lines, flavor-strength lines |
| Physical behaviour | How will it feed and dose in your plant? | Moisture, sieve residue or mesh, bulk behaviour |
| Purity and contaminants | What must not be in it? | Total ash, acid-insoluble ash, sulfites, heavy metals, foreign matter, pesticide residues |
| Hygiene and verification | How does a lot get cleared? | Microbiology counts, sampling plan, certificate items |
Here is the catch: most supplier documents do the first group well and leave the other three thin. A sheet with a beautiful product description but no method names, no basis, and no sampling plan is a flyer, not a specification. The four groups also tell you which questions to send back: physical behaviour questions belong to your production team, purity questions to your quality team, and verification questions to whoever signs off on incoming goods.
Which Document Stands Behind Each Line
On sheets from Chinese suppliers, the standard column hides most of the variation. A dehydrated garlic powder that does not point to a dedicated garlic product standard will cite either the general standard for spices and condiments, GB/T 15691, or the producing company’s own standard; ours is Q/LBY 0004S. Those two documents are not interchangeable, and the general one has just changed. GB/T 15691 was revised on March 31, 2026, and the new edition replaced the 2008 edition on October 1, 2026 (GB/T 15691-2026; the superseded 2008 edition is already marked withdrawn in the national standards database).
The revision list is worth reading once, because it touches lines buyers ask about every week. The 2026 edition deleted the powder and granule product categories, deleted the sieve residue indicator from its technical table and the grinding fineness inspection alongside it, moved the moisture and ash determinations to the national food methods GB 5009.3 and GB 5009.4, and dropped the shelf life clause entirely. Its own general limits are wide, moisture at 14.0 and total ash at 10.0 on a dry basis, with a note that a single spice that has its own product standard follows that standard instead. None of this makes the older sheets wrong. It does mean that a sheet saying only GB/T 15691, with no edition year, is now ambiguous: the same-named lines are measured by different methods in the two editions, and one of the two does not define some of them at all.
International documents work the same way. ISO 5560:1997, last reviewed and confirmed in 2024, is the specification for dehydrated garlic; it defines the product as dried without bleaching or precooking and sets out moisture, total ash, acid-insoluble ash, volatile organic sulfur compounds and cold-water-soluble extract, each against a named test method (ISO 5560). Its commercial forms run from slices through grits to powder, and powder is defined the same way a sieve line should be defined: a homogeneous product, 95 percent of which passes a 250 micron sieve. The ADOGA standards, the North American industry manual for dehydrated onion and garlic, sit closer to plant practice: moisture capped at 6.8 percent for dehydrated garlic, hot-water-insoluble solids and colour indices, particle size windows expressed as screen percentages, lead at 100 parts per billion, and a sulfite decision chain that comes up later in this guide (ADOGA Official Standards and Methods, 15th edition).
Two Grades, Two Sheet Architectures
The fastest way to see that architecture is to look at two real sheets for the same commodity. Our dehydrated garlic powder GP-W04 is documented against the general standard, and its sheet is short and physical: moisture, sieve residue, heavy metals and microbiology, with measured values published next to the ceilings, moisture 4.6 against 5.0 and sieve residue 0.3 against 2.5, the latter a legacy line now carried as a product-level control (GP-W04 specification). Our garlic powder GP-B06 comes off the milling route under an enterprise standard, and its sheet carries a different line set: moisture 6.34 against 8.0, total ash 2.0 against 12.0, acid-insoluble ash 0.86 against 5.0, plus a total nitrogen line (GP-B06 specification). Same commodity words on both pages, completely different document architecture underneath.
Neither architecture is better. A spray-dried or dehydrated route concentrates the garlic solids, so its sheet leans on physical cleanliness and microbiology; a milled route leans on composition lines, because grinding and grading are where identity and mineral content can drift. This is where most buyers trip up when they benchmark suppliers: they compare ceilings, when the comparable items are the measured results, the method names and the basis. A ceiling from an enterprise standard and a ceiling from a general standard are not the same kind of promise, and a ceiling without its method is not a number you can hold anyone to.
Moisture: The Line Your Plant Feels First
Moisture is the first line your production team feels. Flow, caking risk and storage behaviour all move with it, but a result outside the agreed ceiling is a signal, not a verdict: it opens an investigation and a lot disposition decision, and it does not by itself establish caking or microbial growth. Handling behaviour depends on moisture alongside water activity and particle character, and on the packaging and storage conditions the powder meets. Microbiological risk sits with the applicable hazard and control system rather than with moisture alone. The ceiling still matters even where your process would tolerate a wetter powder, because moisture is one of the variables behind how much of the volatile sulfur character survives storage.
The value on the certificate describes the product at packing, not in your warehouse. Dehydrated garlic powders are hygroscopic: they pull moisture from humid air once the barrier is opened. Packaging and storage climate therefore decide how much of the moisture line you actually get on the line, and this is one of the places where caking and flow problems start long before anyone opens the drum.
Read the moisture line with three things in view. First the method: the revised general standard names GB 5009.3, the ADOGA standards specify a vacuum-oven determination at 70 degrees Celsius, and older documents often cite ISO 939. Second the basis: as-is or dry matter, because the two are not the same percentage. Third the ceiling itself, which should come from your application rather than from a neighbouring product: the association standard caps dehydrated garlic at 6.8 percent, the general standard allows 14.0 when no dedicated product standard applies, and our own sheets sit tighter, 5.0 for GP-W04 and 8.0 for GP-B06, with recent lots measured at 4.6 and 6.34. The moisture ceiling in a garlic powder specification is only comparable when the method and basis travel with it.
Sieve Residue and Mesh: The Line That Just Changed Meaning
The sieve line is the oldest line on a garlic sheet, and the one most changed by the 2026 revision. For years, Chinese sheets carried a residue figure of 2.5 grams per 100 grams, and it was never an arbitrary quality number: it came from the earlier edition of the general standard, which drew the boundary between powder and granule with a sieve test, a 0.2 millimetre sieve shaken for four minutes. At or below 2.5 grams of residue, the product classified as powder. The 2026 edition deleted both the classification terms and the sieve residue indicator from its technical table, so a sheet still showing that figure is now quoting a legacy classification, a customer-agreed line, or a company standard, and each of those reads differently.
A usable sieve line has three parts: the aperture, the percentage passing or retained, and the screen standard and shaking convention behind the number. ISO 5560 defines powdered garlic as a homogeneous product with 95 percent passing a 250 micron sieve. The ADOGA particle size windows are expressed as percentages retained on or passing named screens for each commercial form, which is the pattern to copy. The bare mesh shorthand in offers, 80 mesh or 100 mesh, points at a wire cloth aperture, but without a passing percentage and a named screen standard it stays a marketing phrase rather than a specification. If your process depends on grind, the spice grinding process guide walks through how milling choices move these numbers before they ever reach your spec.
Sieve residue drives how the powder behaves downstream: coarse fractions settle out of slurries and show on finished surfaces, fine fractions dust, bridge in feeders and blind screens, and coating lines feel the difference in pickup long before a consumer does. When you compare suppliers, restate every sieve line to aperture plus percentage passing, then look at measured results rather than advertised windows. Our GP-B06 line, for example, keeps a standard fine grind with custom mesh discussed against the order, and the GP-W04 sheet publishes both a legacy residue ceiling, 2.5, and the measured result, 0.3, which is the pair a buyer can actually audit.
Ash and Acid-Insoluble Ash: Mineral Lines Read Honestly
Total ash is what remains after the organic material burns away: the spice’s own minerals plus any soil, dust or mineral additives that came along for the ride. Acid-insoluble ash narrows that remainder to the fraction that does not dissolve in acid, which in practice is mostly soil and grit. ISO 928 and ISO 930 define the two determinations, and the 2026 revision of the general standard routes them through GB 5009.4 on a dry basis, with general ceilings of 10.0 for total ash and 5.0 for acid-insoluble ash where no dedicated product standard applies. The ceiling belongs to the standard that owns the line: ISO 5560 caps acid-insoluble ash at 0.5 percent on a dry basis, while our GP-B06 sheet carries its own enterprise ceiling of 5.0 with a measured 0.86. A result only reads against the ceiling of the document it came from, and those two figures sit in different documents: method and reporting basis have to be aligned before 0.86 can be weighed against the ISO limit. Meeting a declared enterprise specification does not by itself establish conformity with ISO 5560, and read the ceilings that way in any case: they guard against mineral additive abuse as much as they reflect hygiene control, and that is exactly how a buyer should use them.
Both lines are cleanliness indicators with a long paper trail behind them. On cumin, the same two numbers are how buyers catch sand and grit contamination, and the logic transfers directly; the cumin sourcing guide shows the paired reading in practice. Read the trend, not the point: a wet harvest pushes more soil into washing, and if acid-insoluble ash creeps up across consecutive lots, the story is supplier hygiene rather than one unlucky batch. On our GP-B06 sheet the acid-insoluble ash ceiling sits at 5.0 with the latest measured value at 0.86, a headroom pattern worth asking every supplier to publish.
One basis trap applies to the whole group: total ash and acid-insoluble ash on a dry-matter basis are not comparable with as-is figures, and the difference can exceed a tenth of the value. Fix the basis in the contract before fixing the ceiling.
Sulfites: Where the Method Decides the Number
Sulfites earn a line on garlic sheets for a reason that has little to do with garlic itself. Import markets treat sulfiting agents as declarable, and the thresholds are low: in the United States the labeling rules for added sulfites turn on a 10 parts per million detection line and on the agent’s role in the finished food, with both the optimized Monier-Williams method and an LC-MS/MS method written into the regulation (21 CFR 101.100). Other markets run their own versions of the same idea with their own numbers, which is why the real question for a garlic powder specification is never whether a sulfite figure exists, but which method produced it and what threshold it is compared against.
Here is the part that surprises buyers: dehydrated garlic reports sulfur that was never added. Garlic is built from sulfur-bearing flavour precursors, and the classic distillation determination, Monier-Williams, cannot fully separate the spice’s own sulfur from a sulfiting agent, so unsulfited garlic can read well above zero. The association standards for dehydrated onion and garlic address the problem directly: they recommend against added sulfites in the first place, record that readings up to 230 parts per million have been accepted as naturally occurring in the United States, and treat a product measured above 230 by the standard distillation method but at or below 20 by an HPLC method as natural material outside the labeling requirement. Read those figures as the association’s method-specific interpretation, not as a general exemption. The regulation draws the line itself: a sulfiting agent that was added and still performs a technical function in the finished food must be declared, and an added agent with no technical effect counts as insignificant only when no detectable amount is present, with the detectable line at 10 parts per million under the methods the regulation names. The added-sulfite procedures tightened the same logic to a 10 parts per million ceiling, and the modified optimized Monier-Williams methods for dried garlic come with published validation work behind them (Lafeuille et al., 2007; Addala et al., 2016).
Write the sulfite line in a garlic powder specification as a method plus a threshold plus a decision rule: which determination settles the labeling question, which number counts as added rather than natural, and what happens if the methods disagree. A bare sulfite figure with no method attached is unreadable, in both directions: it can fail a clean product and it can mask a sulfited one. The consequences are administrative, not theoretical, which is why undeclared sulfites appear among the detention reasons for dried vegetables, pastes and spice mixes on import alerts (FDA Import Alert 99-21).
Our own dehydrated grade is documented without a sulfur fumigation step, as its product page states, and where a destination market requires a sulfite determination, the test can be agreed as part of the order with the method named up front (GP-W04 specification).
Micro Counts and the Sampling Plan Behind Them
Microbiology lines look like the hardest part of the sheet and are usually the least understood. The plate count is not a safety number: it estimates the general bacterial population, and overall levels do not track the presence or absence of pathogens. What carries weight in a finished-ingredient programme is the specific set. The four indices the ADOGA microbiological recommendations set out for dehydrated onion and garlic are the aerobic plate count; coliforms and E. coli; yeasts and moulds; and a Salmonella absence test, sampled on a 25 gram index composite and a 375 gram Salmonella composite. A staphylococcus ceiling, like the one on our GP-W04 sheet, belongs to the individual SKU or buyer control plan rather than to that core set. The manual also describes the plate count as a general profile rather than a safety verdict.
The number’s meaning depends on the sample behind it. Microorganisms are not distributed uniformly through a dehydrated powder, so a 25 gram grab from a 20 tonne lot is a statement about 25 grams. Industry guidance solves this with a composite sample: 25 grams composited for the index tests and 375 grams for Salmonella, drawn under a plan that records how many containers were probed. Do not skip this step. When the micro lines in a garlic powder specification are copied from supplier to supplier without the sampling plan, nobody can tell whether a difference between two certificates is a difference in product or a difference in probing.
Two practical questions follow. First, whether the testing laboratory works under an accredited system such as ISO/IEC 17025. Second, whether testing is per lot or per control period, because a treatment step that lowers the background load changes what “per lot” needs to mean. Our own sheets keep the numbers concrete: the GP-W04 page publishes a plate count of 200 against a 10,000 ceiling, coliforms below detection, Salmonella not detected, and staphylococcus under 10 against a ceiling of 100 (its micro results). If a high background load is the problem, the fix is usually a validated treatment choice rather than a tighter count, and the trade-offs among the treatment routes (steam, irradiation, fumigation) sit in the spice sterilization methods guide.
Nitrogen and Flavour-Strength Lines
A total nitrogen line, determined by a Kjeldahl method such as GB 5009.5, measures the nitrogen-bearing fraction of the product. In a garlic powder it tracks composition rather than safety, and it appears on sheets produced under company standards, ours included. Read it as a consistency and identity check across lots, not as a flavour score; if a supplier presents a nitrogen figure as a strength claim, ask what range the standard controls it to and how repeatable the method is at that range. The same discipline applied to nitrogen numbers on the savoury side is in our amino nitrogen guide.
Flavour-strength lines are where specification language is weakest. Some sheets quote a volatile oil figure, some an allicin potential, some nothing at all, and the numbers rarely share a method. The ISO specification anchors garlic flavour chemistry in a defined way, through volatile organic sulfur compounds and a cold-water-soluble extract minimum, each against its own method on a dry basis. The association standard takes the practical route instead, with substitution guidance that one part of fancy dehydrated garlic stands in for about five parts of prepared fresh garlic as a starting point for product development. Treat a flavour-strength figure in a garlic powder specification the same way as every line before it: it needs a named method or an agreed sensory protocol with reference samples before it can carry any weight in a contract.
Putting the Sheet Into Your Contract
Switching suppliers is the moment a specification stops being paperwork. The next lot will be judged against whatever you wrote, by people who were not part of the negotiation, so the contract needs the lines that survive translation: a number, a method, a basis, a sampling plan, and a rule for what happens when a value lands outside the window. The same discipline applied to chili heat, from analytical chemistry to disposition, runs through our capsaicin content specification guide.
Four Questions Every Line in a Garlic Powder Specification Should Answer
- Which method, and which edition? A line that names a method but not its edition drifts the moment the method is revised, as the 2026 standard change just demonstrated.
- On what basis? As-is or dry matter, per unit or per weight. Fixing the basis before fixing the ceiling prevents most comparability arguments.
- Sampled how? The result belongs to a sampling plan: how many containers were probed, the composite size, and the handling rules that kept the sample representative.
- Beyond the window? The most valuable sentence in a specification describes disposition: restatement, retest, rejection, or concession with a deviation record.
If a supplier cannot answer the four questions for a line, that line is not ready for the contract yet. It can stay on the sheet as product information, but it should not be treated as a commitment.
| Line | What it guards | What a contract-ready line adds |
|---|---|---|
| Moisture | Flow, caking risk and storage behaviour | Method, basis, ceiling, recent measured history, disposition |
| Particle size | Dispersion in liquids, pickup on coating lines | Sieve aperture plus percentage passing, or mesh plus screen standard; never a bare mesh word |
| Total ash and acid-insoluble ash | Field and process cleanliness | Dry basis stated, trend expectation, escalation rule for consecutive lots |
| Sulfites | Destination-market declaration risk | Named method, threshold, and the natural-versus-added decision rule |
| Heavy metals | Contaminant ceilings for the destination market | Named method, market-specific limit, testing frequency |
| Microbiology | Hygiene and pathogen control | Index set, sample sizes, sampling plan, laboratory accreditation |
| Identity and form | The product you believe you bought | Botanical name, commercial form, product standard and edition |
Heavy metals illustrate why the source of each limit matters. The association standard for dehydrated garlic places lead at 100 parts per billion, a figure set by industry practice for ingredient programmes, while destination markets layer their own contaminant ceilings on top. Chase both numbers for every market you ship to, and write the stricter of the two. Check that the method can see that far as well: where a contract adopts a limit as tight as 0.1 mg/kg, the agreed determination has to report credibly at that level, and a not-detected result against a higher reporting limit does not establish compliance with the stricter ceiling.
Two habits pay for themselves here. Restate both suppliers onto the same basis before you compare anything, and keep a retained baseline sample from the qualification lot; when a dispute starts, the sample plus the specification is the whole argument. The supplier evaluation workflow used for seasoning programmes covers the questionnaire, audit and re-approval side of this model in more detail (seasoning powder supplier evaluation).
What QXFOOD Documents on Its Garlic Powders
We run two garlic products for manufacturing customers, and both are documented in the shape this guide describes. The dehydrated grade GP-W04 ships against the general standard with lot certificates covering moisture, sieve residue, heavy metals and microbiology, and its page publishes measured results next to each ceiling, including the sieve residue pair, 0.3 against 2.5 (the GP-W04 page). The milled grade GP-B06 carries an enterprise-standard line set with moisture, ash, acid-insoluble ash and total nitrogen, a standard fine grind, and custom mesh discussed against confirmed order requirements (the GP-B06 page).
Where your market or your contract template needs a line restated, as a named sieve aperture instead of a residue figure, a dry-matter basis, or a specific sulfite method, that can be agreed as part of the order, and the garlic powder specification documents for the batch follow the agreement. Neither product carries additives, and the dehydrated grade is documented without a sulfur fumigation step. Samples are available before you commit a production lot.
If you want this line-by-line reading applied to your own template, send the specification you are working from and tell us the destination market. We will map it against the documents our two grades can provide, and flag anything that needs a test run before it becomes a contract line. The contact page is the fastest way to start that conversation.
Frequently Asked Questions
What is a garlic powder specification?
A garlic powder specification is the set of lines a purchase is judged against, grouped by what they answer: identity and composition; physical behaviour; purity and contaminants; hygiene and verification. A line becomes usable when it carries a limit, a method and edition, a reporting basis, a sampling plan, and a rule for lots outside the window.
Is dehydrated garlic the same as garlic powder?
In trade, dehydrated garlic names a family: slices, flakes or pieces, grits and powder, all produced by drying peeled cloves without bleaching or precooking, as ISO 5560 defines it. Powdered garlic is the finest form in that family, defined in the same standard as a homogeneous product with 95 percent passing a 250 micron sieve. When a sheet says only dehydrated garlic, confirm which form is quoted before comparing particle lines.
What does sieve residue mean in a garlic powder specification?
Historically it meant the residue left on a 0.2 millimetre sieve after four minutes of shaking, with 2.5 grams per 100 grams as the powder-versus-granule boundary in the earlier general standard. The 2026 revision deleted that indicator along with the classification terms, so today the line is a legacy figure, a customer requirement, or a company-standard limit. Ask which, and restate it as an aperture plus a percentage passing.
Why do two suppliers cite different standards on their garlic sheets?
Because the frameworks differ by intent. A Chinese sheet may cite the general standard for spices and condiments or the producer’s own company standard; an export-oriented sheet may quote ISO 5560; a programme sheet for North American buyers may quote the ADOGA standards. None of them is wrong, and they are not interchangeable either. Compare measured results, methods and bases, then agree which document governs your contract.
How should sulfites be specified for dehydrated garlic?
As a method plus a threshold plus a decision rule. Garlic’s natural sulfur compounds inflate the classic distillation method, so the association’s interpretation treats a product measured above 230 parts per million by distillation but at or below 20 by HPLC as natural material, and its added-sulfite methods work to a 10 parts per million ceiling, as method-specific reference values rather than a general exemption. Name one method as the referee, state the threshold, and define what happens when the methods disagree.
What moisture limit should I put in a garlic powder specification?
Start from your storage and process conditions, then verify against supplier capability. The industry standards for dehydrated garlic cap moisture at 6.8 percent, while our own two grades document 5.0 and 8.0 ceilings with recent lots measured at 4.6 and 6.34. Whatever limit you set, write it with the method and the basis, because a moisture ceiling on its own is not reproducible.
Do I need microbiology on every lot?
That depends on your control plan and the product’s downstream use. The index set to require is consistent: the aerobic plate count and the coliform group, plus yeast and mould counts and a Salmonella absence test, and the sampling plan matters as much as the limits. The association’s recommended sampling approach pairs a 25 gram composite for the standard indices with 375 grams for Salmonella, as a defined reference plan rather than a universal requirement. If incoming lots carry a variable background load, discuss a validated treatment step rather than only tightening counts.
Which documents does QXFOOD provide for its garlic powders?
Each grade ships with a lot certificate against its declared standard: GP-W04 against the general standard, GP-B06 against its enterprise standard, both with measured values published on the product pages. Additional or restated lines, including named sieve specifications and destination-market test items, can be agreed as part of the order.
Learn More
- Powder caking and flow: causes and prevention for seasoning powders
- Spice grinding: how milling choices set particle size before the spec does
- Spice procurement: standards, supplier qualification and batch continuity
- The capsaicin content specification: the same discipline applied to chili heat
- Discuss a garlic powder specification with QXFOOD