{"schema":"https://ver.cy/schemas/card/1.0.0","id":"vr.tr.curdlan","code":"thing-q616242","url":"https://ver.cy/models/thing/q616242/","name":"curdlan","alternateNames":[],"kind":"thing","status":"published","version":"0.1.0-research.1","language":"en","classifiers":{"family":"Thing Registry","category":"Physical world and living systems","entryKind":"thing","plane":"PHY","domain":["PHY.MAT"],"industry":[],"navPath":"","tags":[],"facets":{}},"whatItIs":"Curdlan is a predominantly linear, unbranched bacterial polysaccharide composed of D-glucose residues joined by β-(1→3) glycosidic bonds, distinguished by its ability to form gels when aqueous dispersions are heated.","purpose":"Enable an agent to identify curdlan, assess a particular lot and its gel-forming state, and determine whether it meets a specified use.","scope":{"in":["Identity and structural confirmation of unmodified curdlan","Production provenance, grade, purity and lot variability","Powder, aqueous dispersion, alkaline solution and gel states","Thermal history and measured gel performance","Storage condition, handling requirements and use-specific acceptance"],"out":["Production organisms as biological entities","Fermentation plants and manufacturing process design","Complete foods or other formulated products containing curdlan","Chemically modified curdlan derivatives as separate materials","Clinical efficacy claims and therapeutic treatment protocols"],"boundaries":[]},"distinguishingFeatures":["Confirm a linear β-(1→3)-D-glucose backbone; the label beta-glucan alone does not establish curdlan identity. [Manufacturer description](https://ajibana.jp/closeup/10155/)","Check water and ethanol insolubility together with dissolution under specified alkaline conditions; visual dispersibility alone is insufficient. [JECFA identification specification](https://www.fao.org/4/x3860e/X3860E12.htm)","Verify formation of an elastic gel after heating an aqueous suspension under a documented protocol. [JECFA definition and gel test](https://www.fao.org/4/x3860e/X3860E12.htm)","Require production provenance as well as structural evidence when differentiating curdlan from another material described only as β-1,3-glucan.","Distinguish unmodified curdlan from a derivative or blend through substitution analysis and declared composition."],"structure":{"bundles":[{"id":"curdlan-identity","name":"Curdlan identity","description":"Establish whether the material belongs to this registry entry.","layers":[{"id":"backbone-confirmation","name":"Backbone confirmation","description":"Record evidence for the expected glucose linkage architecture.","findings":[{"id":"linkage-specific-identification","name":"Linkage-specific identification","description":"Require a method capable of distinguishing linkage patterns and detecting branching or substitution.","questions":[{"text":"What analytical evidence establishes the β-(1→3)-D-glucose backbone and evaluates branching?","id":"linkage-specific-identification-q01","kind":"measurement"},{"text":"What result would classify this sample as another glucan, a blend or a curdlan derivative?","id":"linkage-specific-identification-q02","kind":"boundary"}]}]},{"id":"identifier-and-origin","name":"Identifier and origin","description":"Connect the material name to authenticated production provenance.","findings":[{"id":"identity-record-concordance","name":"Identity record concordance","description":"Resolve agreement between chemical identifiers, supplier naming and producer records.","questions":[{"text":"Which source verifies that the assigned chemical identifiers refer to unmodified curdlan?","id":"identity-record-concordance-q01","kind":"provenance"},{"text":"Which production organism and strain are documented, including historical naming where necessary?","id":"identity-record-concordance-q02","kind":"provenance"}]}]}]},{"id":"lot-composition-and-grade","name":"Lot composition and grade","description":"Represent curdlan content, polymer variability and production residues.","layers":[{"id":"polymer-content","name":"Polymer content","description":"Separate measured curdlan content from moisture and other carbohydrate contributions.","findings":[{"id":"assay-and-chain-distribution","name":"Assay and chain distribution","description":"Interpret assay and molecular mass results with their analytical limitations.","questions":[{"text":"What is the curdlan mass fraction, on which moisture basis, and how specifically does the assay measure curdlan?","id":"assay-and-chain-distribution-q01","kind":"measurement"},{"text":"What molecular mass distribution was measured, and did sample dissolution or preparation alter the polymer?","id":"assay-and-chain-distribution-q02","kind":"measurement"}]}]},{"id":"purification-and-residues","name":"Purification and residues","description":"Connect fermentation-derived material to relevant impurity controls.","findings":[{"id":"grade-evidence","name":"Grade evidence","description":"Treat grade as a supported conformity claim tied to a particular lot.","questions":[{"text":"Which purification records and lot tests establish residual protein, ash, metals and microbiological quality?","id":"grade-evidence-q01","kind":"provenance"},{"text":"Which additional residue or biological-contaminant tests does the intended application require?","id":"grade-evidence-q02","kind":"action"}]}]}]},{"id":"dispersion-and-gel-transitions","name":"Dispersion and gel transitions","description":"Track preparation conditions and transitions into functional gel states.","layers":[{"id":"dispersion-and-dissolution","name":"Dispersion and dissolution","description":"Distinguish suspended particles from dissolved polymer.","findings":[{"id":"preparation-state-verification","name":"Preparation state verification","description":"Record powder wetting, dispersion uniformity and any alkaline dissolution treatment.","questions":[{"text":"At the stated concentration, pH and mixing conditions, is curdlan suspended, dissolved or incompletely dispersed?","id":"preparation-state-verification-q01","kind":"measurement"},{"text":"If alkali was used, what neutralization and residual-ion checks are required before the next operation?","id":"preparation-state-verification-q02","kind":"action"}]}]},{"id":"thermal-setting-path","name":"Thermal setting path","description":"Record heating, cooling and reheating as part of the material state.","findings":[{"id":"gel-state-and-reversibility","name":"Gel state and reversibility","description":"Determine gel formation and reversibility experimentally without assigning universal temperature thresholds.","questions":[{"text":"What temperature-time and cooling sequence produced the observed gel at this concentration?","id":"gel-state-and-reversibility-q01","kind":"measurement"},{"text":"Does the gel reverse or retain its structure during a specified reheating cycle?","id":"gel-state-and-reversibility-q02","kind":"measurement"}]}]}]},{"id":"gel-performance","name":"Gel performance","description":"Evaluate texture and retained function under intended service conditions.","layers":[{"id":"mechanical-response","name":"Mechanical response","description":"Measure the gel using reproducible mechanical protocols.","findings":[{"id":"comparable-gel-measurements","name":"Comparable gel measurements","description":"Attach preparation, geometry and test conditions to every reported gel-strength value.","questions":[{"text":"What breaking stress or rheological response is measured at the stated concentration, specimen age and temperature?","id":"comparable-gel-measurements-q01","kind":"measurement"},{"text":"Are compared results compatible in probe geometry, deformation rate, units and thermal preparation?","id":"comparable-gel-measurements-q02","kind":"boundary"}]}]},{"id":"matrix-and-storage-response","name":"Matrix and storage response","description":"Evaluate curdlan performance in the intended surrounding medium and handling cycle.","findings":[{"id":"retained-gel-function","name":"Retained gel function","description":"Record performance changes caused by formulation conditions and subsequent treatment.","questions":[{"text":"How do the intended pH, salts and co-ingredients affect gel formation and water release?","id":"retained-gel-function-q01","kind":"measurement"},{"text":"What acceptance limits apply after storage, freezing and thawing, reheating or shear where those operations are intended?","id":"retained-gel-function-q02","kind":"action"}]}]}]},{"id":"use-qualification-and-care","name":"Use qualification and care","description":"Connect material condition and evidence to specific handling and use decisions.","layers":[{"id":"application-qualification","name":"Application qualification","description":"Match the lot to dated requirements for its proposed use.","findings":[{"id":"permitted-and-supported-use","name":"Permitted and supported use","description":"Separate intended technical function, specification compliance and jurisdictional authorization.","questions":[{"text":"Which current authority and specification govern this curdlan grade, application and jurisdiction?","id":"permitted-and-supported-use-q01","kind":"provenance"},{"text":"Does the lot satisfy the applicable composition, performance and use conditions, or must it remain on hold?","id":"permitted-and-supported-use-q02","kind":"action"}]}]},{"id":"handling-and-condition","name":"Handling and condition","description":"Preserve powder and prepared-material suitability through storage and handling.","findings":[{"id":"condition-dependent-handling","name":"Condition-dependent handling","description":"Use supplier evidence and observed condition to determine precautions and retesting needs.","questions":[{"text":"What does the applicable SDS establish about powder handling, classification and any relevant exposure limits?","id":"condition-dependent-handling-q01","kind":"provenance"},{"text":"Which moisture exposure, packaging breach, contamination observation or prepared-sample holding time triggers retesting or rejection?","id":"condition-dependent-handling-q02","kind":"action"}]}]}]},{"id":"evidence-and-external-alignment","name":"Evidence and external alignment","description":"What the world already says about this thing, gathered so the model can be checked against it.","layers":[{"id":"reported-evidence","name":"Reported evidence","description":"Findings from the breadth pass, kept separate from the structural claims.","findings":[{"id":"evidence-confidence-notes","name":"Check these first","description":"Recalled without web access and unsourced; every item is a lead to verify.","questions":[{"text":"Which of these check these first hold for the sense of curdlan this model covers, and on what evidence?","id":"evidence-confidence-notes-q01","kind":"provenance"}]},{"id":"evidence-kinds","name":"Kinds and varieties","description":"Recalled without web access and unsourced; every item is a lead to verify.","questions":[{"text":"Which of these kinds and varieties hold for the sense of curdlan this model covers, and on what evidence?","id":"evidence-kinds-q01","kind":"provenance"}]},{"id":"evidence-identifiers","name":"Identifiers and schemes","description":"Recalled without web access and unsourced; every item is a lead to verify.","questions":[{"text":"Which of these identifiers and schemes hold for the sense of curdlan this model covers, and on what evidence?","id":"evidence-identifiers-q01","kind":"provenance"}]},{"id":"evidence-standards-and-regulation","name":"Standards and regulation","description":"Recalled without web access and unsourced; every item is a lead to verify.","questions":[{"text":"Which of these standards and regulation hold for the sense of curdlan this model covers, and on what evidence?","id":"evidence-standards-and-regulation-q01","kind":"provenance"}]},{"id":"evidence-real-world-use","name":"Real-world use","description":"Recalled without web access and unsourced; every item is a lead to verify.","questions":[{"text":"Which of these real-world use hold for the sense of curdlan this model covers, and on what evidence?","id":"evidence-real-world-use-q01","kind":"provenance"}]},{"id":"evidence-measurements","name":"Typical measurements","description":"Recalled without web access and unsourced; every item is a lead to verify.","questions":[{"text":"Which of these typical measurements hold for the sense of curdlan this model covers, and on what evidence?","id":"evidence-measurements-q01","kind":"provenance"}]},{"id":"evidence-failure-modes-and-hazards","name":"Failure modes and hazards","description":"Recalled without web access and unsourced; every item is a lead to verify.","questions":[{"text":"Which of these failure modes and hazards hold for the sense of curdlan this model covers, and on what evidence?","id":"evidence-failure-modes-and-hazards-q01","kind":"provenance"}]},{"id":"evidence-neighbours","name":"Neighbouring kinds and how to tell them apart","description":"Recalled without web access and unsourced; every item is a lead to verify.","questions":[{"text":"Which of these neighbouring kinds and how to tell them apart hold for the sense of curdlan this model covers, and on what evidence?","id":"evidence-neighbours-q01","kind":"provenance"}]}]}]}]},"agentConduct":{"may":["Describe curdlan, its gel-forming properties and its uses in food and research.","Report its authorized food uses as published by the relevant authority."],"mustNot":["Claim health benefits for it beyond what authorities have accepted.","Use it in foods where it is not authorized or above permitted levels.","Hide it from ingredient labels."],"requiresHuman":["Approving its use in a food product formulation."]},"ethics":{"considerations":["Consumers rely on honest labels for diet and allergies.","Additives raise trust issues when their use is hidden."],"affectedParties":["Consumers","Food producers"]},"owners":{"steward":"The producer or seller; food safety authorities authorize its use.","roles":[],"masterSystems":[]},"relations":[{"target":"Q5420648","type":"parent","note":"registry parent class"},{"target":"Q75241881","type":"parent","note":"registry parent class"}],"interaction":{"identity":{"applicability":"required","items":["Vercy registry: vr.tr.curdlan","Wikidata: Q616242 (https://www.wikidata.org/wiki/Q616242)"]},"properties":{"applicability":"required","items":["Registry and chemical identity: vr.tr.curdlan; CAS 54724-00-4, with source and identifier scope","Linkage and branching profile: Linkage fractions in mol%; branching detected/not detected with method and detection limit","Molecular mass distribution: Mn and Mw in g/mol; dispersity dimensionless; dissolution and analytical method required","Curdlan assay: Mass%; as-received or dry basis; assay method and specificity","Production origin and declared grade: Producer, strain designation, manufacturing lot, purification record and applicable grade specification","Moisture and particle size: Water or loss on drying in mass%; particle-size distribution in µm, with methods","Preparation state: Dry powder; aqueous suspension; alkaline solution; gel; degraded or indeterminate","Preparation conditions: Curdlan concentration with mass or volume basis; pH; temperature in °C; time in min; mixing conditions","Gel mechanics and thermal reversibility: Breaking stress, G' and G″ in Pa; strain in %; reversible/irreversible/untested under a stated thermal cycle","Contaminant and microbiological profile: Analyte-specific mg/kg; microbial counts in CFU/g; absence tests with sample mass; application-specific biological contaminants where relevant","Handling and regulatory evidence: Supplier SDS revision; jurisdiction; intended application; governing specification; assessment date"]},"recognition":{"applicability":"required","items":["A white to off-white odourless powder.","Forms a firm gel when a water mixture is heated."]},"capabilities":{"applicability":"required","items":["Authenticate a lot using structural, provenance and functional evidence.","Calculate a preparation on a stated curdlan assay and moisture basis.","Select and verify a dispersion or gel-setting protocol for a target texture.","Compare lots using the same thermal preparation and mechanical test.","Release, hold or reject material against a documented application specification.","Identify when storage or processing changes require renewed testing."]},"hazards":{"applicability":"required","items":["Fine powder can irritate the airways when handled in bulk."]},"interfaces":{"applicability":"required","items":["The Joint Food and Agriculture Organization and World Health Organization Expert Committee on Food Additives publishes identity and purity specifications for curdlan used as a food additive."]},"context":{"applicability":"required","items":["Curdlan is used as a heat-induced gelling and texture-modifying ingredient in food applications where permitted.","It is also encountered in research on bacterial polysaccharides, hydrogels and biomaterials.","Its suitability depends on the material grade, purity and gel behavior under the intended processing conditions."]}},"sources":[{"title":"Wikidata item Q616242: curdlan","url":"https://www.wikidata.org/wiki/Q616242","note":"identity and sense of the item"},{"title":"Wikipedia: Curdlan","url":"https://en.wikipedia.org/wiki/Curdlan","note":"general description of the item"}],"openQuestions":["Which EC and PubChem records, if any, unambiguously represent unmodified curdlan at this registry granularity?","What temperature-time-concentration ranges distinguish reversible and irreversible gel behavior for the relevant grades under comparable tests?","Which analytical methods reliably separate curdlan content from other carbohydrates and determine molecular mass without preparation artifacts?","Which current jurisdiction-specific permissions, impurity limits and supplier hazard classifications apply to the intended grade and use?","What thermal-decomposition and storage-stability evidence is available, and should melting and boiling points be recorded as not applicable rather than as numerical constants?"],"resources":{"spec":"/models/things/publications/thing-q616242/spec.json"},"provenance":{"origin":"thing registry research (pass 2)","builtFrom":["models/things/publications/thing-q616242/spec.json"],"providers":["Codex"],"researchStatus":"unreviewed","generatedAt":"2026-09-12T08:56:54Z","builder":"tools/build_cards.py@1.0.0"},"completeness":{"sections":{"classifiers":"filled","whatItIs":"filled","purpose":"filled","distinguishingFeatures":"filled","structure":"filled","agentConduct":"filled","ethics":"filled","owners":"filled","relations":"filled","interaction.identity":"filled","interaction.properties":"filled","interaction.recognition":"filled","interaction.capabilities":"filled","interaction.hazards":"filled","interaction.interfaces":"filled","interaction.context":"filled","sources":"filled"},"notes":{"_gate":"Published through the thing publication gate 1.0 on 2026-10-07T10:10:32+00:00: completeness 1.00; sense: Wikidata description; 2 live sources; review by codex: pass"},"score":1.0}}