Gum Arabic Crystal Grades Explained

“Gum arabic crystals” is a useful description for whole or broken natural gum tears. It is not, by itself, a complete grade or a food-grade specification. A workable purchase contract still needs to define the botanical species, trade grade, whole and broken content, size distribution, colour or reference sample, foreign-matter limit, sampling plan and analytical requirements.

That distinction matters because two bags can both be sold as crystals while containing visibly different material—and because a visually clean lot can still fail a moisture, microbiological or contaminant requirement.

What does “gum arabic crystals” mean?

The FAO/WHO JECFA gum arabic specification describes Acacia senegal gum as a pale-white to orange-brown solid with a glassy fracture. Better grades may occur as whole, rounded tears of varying size; broken surfaces appear paler and more glass-like. JECFA also recognises flakes, granules, powder and spray-dried material.

For procurement, a clear description is:

Gum arabic crystals: cleaned whole or broken natural tears, with the species, physical grade and acceptance criteria stated separately.

Do not treat crystal, HPS, Hashab, food grade and E414 as interchangeable terms. They refer to different things:

crystal describes a visible physical form;
HPS is an established trade-grade name;
Hashab is a Sudanese trade term associated with Acacia senegal gum;
food grade concerns conformity with a named food specification and safety controls;
E414 identifies gum arabic as a food additive, not a crystal size or sorting grade.

For the species background, compare Acacia senegal and Acacia seyal and read What Is Hashab Gum Arabic?.

HPS, cleaned, siftings and kibbled: established trade terms

Older FAO trade references document the Sudanese terminology below. The Sudanese Standards and Metrology Organization catalogue also lists separate standards for gum arabic, cleaned gum, HPS, dust, kibbled gum, sampling, solubility, contaminants, mechanically milled powder and spray-dried powder.

These names are useful, but the public catalogue does not provide all numerical limits. The contract should therefore name the applicable standard and edition—or set out the agreed tolerances directly.

Trade term	Practical meaning	What the buyer must still define
HPS — Hand-Picked Selected	Selected clean, whole tears, traditionally described as relatively uniform and light in colour	Species, whole-tear percentage, measurable size bands, colour reference and defect limits
Cleaned / cleaned amber sorts	Cleaned material that may include whole and broken pieces, including darker or irregular nodules	Permitted broken content, foreign matter, colour range and analytical criteria
Cleaned and sifted	Sorted gum after separation of selected pieces and smaller fractions	Sieve method, retained fractions and allowed undersize
Siftings	Smaller pieces separated during sieving	Size distribution, dust limit and whether the form suits the process
Dust	Fine material passing the finest sieve in the relevant sorting process	Whether it is permitted at all and the maximum mass percentage
Kibbled	Gum size-reduced and screened into smaller, more uniform granules	Target granule distribution, fines and processing route

“HPS” alone does not prove food-grade conformity, and “cleaned” does not mean sterile. Expand abbreviations in the RFQ and attach measurable acceptance criteria.

Species, colour and origin are separate checks

JECFA includes gum from Acacia senegal and Acacia seyal. Its identity method uses optical rotation under specified conditions: the two species show opposite directions of rotation. It also describes Acacia seyal gum as more brittle and notes that tear shape and colour can vary by botanical source.

UNCTAD’s gum arabic report distinguishes Acacia senegal “hard gum” from Acacia seyal “friable gum” and describes Acacia senegal material as generally lighter in colour. “Generally” is important. Natural gum has a broad colour range, so colour alone is not reliable proof of species, purity or origin.

Use separate evidence for separate claims:

species: named botanical identity plus an agreed identity method;
colour: an approved physical reference sample or objective measurement method;
origin: batch-linked traceability and country-of-origin records;
single-source or regional claims: chain-of-custody evidence tied to the lot.

Optical rotation may support species identity, but it cannot establish the farm, region or chain of custody on its own.

Visible cleanliness is not the same as food-grade conformity

JECFA notes that commercial gum may contain extraneous material such as sand and bark, which must be removed before food use. Visual inspection is therefore important, but it is only one layer of approval.

A lot can look clean and still fail an analytical requirement. A darker natural piece is not automatically contamination. Keep the following controls distinct:

Physical sorting: bark, sand, fibres, stones, dust, discoloured pieces and other defined defects.
Identity: botanical source and gum-arabic identity tests.
Composition and purity: moisture or loss on drying, ash, acid-insoluble matter and other applicable specification fields.
Food safety: agreed microbiological and contaminant limits.
Traceability: supplier, processor, lot, origin and pack identification.

If the purchase is for food manufacture, “food-grade HPS” should mean both the agreed physical HPS grade and conformity with the named destination-market specification, supported by the offered lot’s evidence. Review the product specification and batch certificate of analysis together.

Turn size descriptions into a testable requirement

Words such as “whole,” “large,” “medium” and “uniform” are not acceptance criteria until the parties attach a method and tolerances to them. There is no buyer-safe universal crystal-size band to copy into every contract.

Specify:

the sieve series and test method;
percentage by mass in each required size band;
maximum oversize and undersize;
minimum whole-tear content, if appearance matters;
maximum broken pieces, siftings and dust;
whether kibbled material is permitted;
sample mass and reporting or rounding rules.

The right limits depend on the downstream process. A processor planning to mill the material may accept a different whole-tear distribution from a buyer selling visible selected tears.

Agree sampling before the shipment moves

A supplier photograph or a handful taken from the top of one bag is not representative evidence for a multi-bag lot. The current Codex General Guidelines on Sampling describes an acceptance plan as one that states both the sample size and the associated lot-acceptance criteria.

Before shipment, agree:

what constitutes one lot;
how many bags or increments will be selected and how they are chosen;
whether testing uses a composite sample, individual bag samples or both;
who samples, who witnesses and where inspection occurs;
how samples are sealed, labelled and transported;
the laboratory and named test methods;
retained and split samples for each party;
acceptance, retest and dispute rules.

The plan should reflect lot size, expected homogeneity, the type of defect, and the commercial risk of accepting or rejecting the wrong lot. An inspection company can carry out sampling, but the contract still needs to state the instructions it must follow.

A practical crystal acceptance schedule

Use a schedule like this as the front page of the product requirement. Populate the limits with your technical team and the applicable standard; do not leave the key fields as adjectives.

Contract field	What to state
Product identity	Gum arabic/acacia gum and exact botanical species or permitted composition
Origin and traceability	Country or region claim and the batch records required to support it
Physical form	Whole tears, cleaned whole/broken crystals, siftings or kibbled granules
Trade grade	Full grade name, supplier code and applicable standard/edition
Whole/broken content	Method and acceptance percentages
Size distribution	Sieve method, required bands, oversize and undersize limits
Colour and appearance	Approved reference sample or objective method and tolerance
Foreign matter	Defined defect categories, method and maximum level
Food-grade criteria	Named destination specification, contaminants and microbiological schedule
Lot evidence	Specification, lot COA, traceability and any required current certificates
Packaging	Food-contact liner or pack, net mass, seal condition and lot marking
Inspection	Sampling plan, inspection point, witness, retained sample and remedy

Pair this schedule with the bulk packaging and storage controls and the supplier due-diligence questions.

RFQ wording you can adapt

Please quote cleaned Acacia senegal gum arabic crystals in 25 kg bags. State the full trade grade and applicable standard, whole/broken content, sieve distribution, colour reference, foreign-matter limit, origin and lot traceability. Include the product specification, representative lot COA, proposed sampling plan, packaging specification and a representative sample. Identify every exception to our acceptance schedule in the quotation.

Our cleaned Acacia senegal crystal product page sets out the stocked commercial format. For a sample, bag, pallet or tonne requirement, request a crystal quotation.

Frequently asked questions

Is “gum arabic crystal” an official grade?

Not by itself. It describes the visible solid form. The purchase specification should separately name the species, trade grade, size and defect tolerances, analytical criteria and sampling plan.

Does HPS mean food grade?

No. HPS is a physical trade designation associated with selected whole tears. Food-grade approval also requires conformity with the named food specification and lot evidence.

Are light-coloured crystals purer?

Colour can be a commercial appearance criterion, but it does not replace identity, purity, microbiological, contaminant or traceability evidence.

Are gum arabic crystals always Acacia senegal?

No. Confirm the botanical source on the product documents and with the agreed identity method. Do not infer species from the word “crystal.”

Should I inspect every bag?

The inspection level should come from a risk-based, agreed sampling plan. It should define the lot, sample selection, acceptance criteria, retained samples and dispute procedure before shipment.