A drum labelled simply "glycerin" can feed a face-cream line or a closed-loop cooling system — and the only thing separating those two destinies is the purity grade and the documents behind it. Glycerin (glycerol) is one of the rare chemicals that sits at the intersection of cosmetics, food, pharmaceutical syrups and heavy industry at the same time. Buying the right grade with the right paperwork protects your formulation; buying the wrong one means either wasted money or a compliance error that is hard to undo once the product ships. This guide collects everything an industrial buyer needs in one place.
What Is Glycerin (Glycerol)?
Glycerin — chemical name glycerol, IUPAC name propane-1,2,3-triol — is a clear, colorless, practically odorless, highly viscous and slightly sweet liquid with CAS number 56-81-5. In food legislation it is listed as additive E422.
The molecule carries three hydroxyl (-OH) groups, and this triol structure gives it two defining behaviors: it mixes with water in all proportions, and it pulls moisture out of the surrounding air — it is strongly hygroscopic. These two properties unlock nearly every application glycerin has. The humectant that binds water into skin in a cream, the moisture retainer that keeps a snack bar soft, the carrier that gives a cough syrup its body and sweetness — all are the same molecule playing different roles.
On the market, "glycerin," "glycerol," "VG" (vegetable glycerin) and "E422" all point to the same molecule. The commercial distinction is never in the name; it is in the source and the purity grade, and those two axes are the backbone of this guide.
Key Physical and Chemical Properties
Here are the parameters purchasing and process teams reference most often, in a single table:
| Property | Typical Value | Note |
|---|---|---|
| CAS number | 56-81-5 | Single, fixed identity |
| IUPAC name | Propane-1,2,3-triol | Trade names: glycerin / glycerol |
| Food additive code | E422 | Humectant, sweetener |
| Molecular weight | 92.09 g/mol | — |
| Density (20 °C) | ~1.26 g/cm³ | Noticeably heavier than water |
| Boiling point | ~290 °C | With decomposition at high heat |
| Melting point (pure) | ~18 °C | Supercools rather than freezing in practice |
| Flash point | ~160–199 °C | Low fire-risk class |
| Viscosity (20 °C, 99.5%) | ~1,400 mPa·s | Honey-like flow |
| Water solubility | Miscible in all proportions | Also fully miscible with ethanol |
| Sweetness | ~60% of sucrose | ~4.3 kcal/g energy value |
These figures are typical for 99.5% refined glycerin. Always verify the actual values of the batch you receive against its lot-specific COA (Certificate of Analysis) — water content, read together with density, is the fastest indicator of real purity.
Vegetable or Synthetic Glycerin?
Glycerin is produced by two main routes, and on the buying side the "source" question comes up as often as the grade question.
Vegetable glycerin is obtained as a co-product of plant oils — palm, coconut, soybean, rapeseed — through saponification, hydrolysis or the transesterification step of biodiesel production. The crude glycerin leaving these processes runs at roughly 70–88% purity; distillation and bleaching turn it into refined product at 99.5% and above. The large majority of global supply today comes from this oleochemical and biodiesel route.
Synthetic glycerin is made from propylene via the epichlorohydrin route. It offers a consistent, narrow impurity profile, but its market share is far smaller and its price generally higher.
The critical point: once refined, the two products are chemically identical. What creates the difference is the marketing and compliance claims of your finished product:
- E-liquid (VG) producers almost always require vegetable origin — the very name "VG" encodes that expectation.
- Cosmetic and food products carrying vegan, halal or kosher claims need a vegetable-origin declaration plus the supporting certificates.
- Buyers with non-GMO requirements will ask about the source oil and its supply-chain documentation.
A "vegetable glycerin" claim is supported not by the label but by the supplier's origin declaration and certificate chain. Requesting those documents at the quotation stage prevents marketing crises later.
Glycerin Purity Grades: USP, Food and Technical
When buying glycerin, the first question is not the quantity — it is the grade. The same CAS number serves entirely different markets depending on purity and impurity profile, and the price tiers follow:
| Grade | Typical Purity | Conformity Reference | Typical Use |
|---|---|---|---|
| Crude glycerin | 70–88% | — | Refinery feedstock, technical intermediate |
| Technical grade | 95–99% | House / technical specification | Antifreeze and heat transfer, resins, textile-paper, mold release |
| USP / Ph. Eur. (pharma) | ≥ 99.5% | USP-NF / Ph. Eur. monograph | Cosmetics, pharmaceutical syrups, personal care, e-liquid (VG) |
| Food (E422 / FCC) | ≥ 99.5% | FCC / E422 food conformity | Humectant, sweetener, flavor carrier in food |
In practice, USP and food grade are usually produced in the same high-purity band; the distinction lies in which monograph the product is tested and released against and which declarations accompany it. Technical grade is perfectly adequate for resins, antifreeze and textiles — but it is not suitable for food, cosmetic or pharmaceutical contact.
A purity percentage on its own can mislead. The most critical item in the USP monograph is not the assay figure but the diethylene glycol (DEG) and ethylene glycol (EG) limit test. The poisoning cases historically linked to contaminated syrups were traced to DEG blends sold as glycerin. For pharma and food purchases, seeing the DEG/EG test reported and within limits on the COA is a non-negotiable condition.
Glycerin in Cosmetics: The Benchmark Humectant
Cosmetics is glycerin's most visible stage. Under its INCI name "Glycerin," it is one of the three most frequently used cosmetic ingredients in the world, and its moisturizing performance is the reference against which other humectants are measured.
The working principle follows from the triol structure: glycerin draws water from the environment and from deeper skin layers and binds it in the stratum corneum. The result is skin that is more supple, flakes less and has a better-supported barrier function. Typical use levels vary with the formulation target:
- Lotions and toners: 2–5%
- Creams and intensive care: 5–10%
- Liquid soap and shampoo: 2–5% (softens the foam feel)
- Toothpaste: 20–30% (humectant plus body)
- Transparent (glycerin) soap: 10–25% depending on the base
A note for soap producers: traditional saponification releases glycerin as a by-product anyway; in transparent bars and liquid formats, however, it is the added refined glycerin that determines both clarity and skin feel. Balancing the drying effect of anionic surfactants against glycerin is one of the core formulation decisions — we cover that interaction in detail in our surfactants guide.
What our cosmetic customers ask for on the sourcing side is consistent: USP-grade purity, a vegetable-origin declaration and a lot-specific COA. You will find the other raw materials most often paired with glycerin on our cosmetics industry page.
Glycerin in Food and Pharma: What E422 Does
On the food side, glycerin performs three core jobs under the code E422:
- Humectant: In cakes, bars, dried fruit and pet food it balances water activity, keeps the product soft and extends shelf life.
- Sweetener: Roughly 60% as sweet as sucrose at ~4.3 kcal/g; as a sugar alcohol it suits tooth-friendly formulations.
- Carrier/solvent: Dissolves flavors and colors, and controls crystallization in confectionery such as fondant and marshmallow.
In pharmaceuticals, glycerin appears as the sweetener and body-builder in cough syrups and elixirs, as the active ingredient in glycerin suppositories, and as an emollient in topical preparations. Every one of these applications requires product conforming to the USP/Ph. Eur. monograph with fully traceable lot records.
The practical rule for food and pharma purchasing: at the quotation stage, request the food-contact declaration, the current SDS and a sample COA; at delivery, verify that the lot number on the COA matches the package label exactly. These three steps eliminate nearly every problem an audit could raise.
Industrial Applications: From E-Liquid to Heat Transfer
Glycerin's industrial application map is broader than almost any other single chemical.
E-liquid (VG): Vegetable glycerin is the main carrier of e-cigarette liquids; the VG ratio determines vapor density. The standard expectation in this market is product that is at least 99.5% USP purity, vegetable-origin and DEG/EG tested. When designing the VG/PG ratio you also need to know the propylene glycol side — our monopropylene glycol (MPG) guide is the right starting point for that comparison.
Antifreeze and heat transfer: Glycerin-water mixtures are the non-toxic alternative to glycols for plants that need freeze protection with contact risk. Mixtures of 60–70% glycerin by weight protect down toward the -40 °C band, which makes them a preferred choice in food plants and closed loops with contact exposure. Because of the high viscosity, pump and pipe sizing should follow the supplier's mixture curves.
Textile and paper: In textile finishing it works as a fiber softener and moisture regulator and as a rheology aid in printing pastes; in paper and cellophane it acts as a plasticizer, preventing embrittlement.
Cleaning and detergents: In liquid soap, dishwashing liquid and surface cleaners it improves skin feel and supports low-temperature product stability. The full raw-material map of this product family is in our cleaning and detergent chemicals article.
Other applications: A building block in alkyd resins and polyurethane polyols, a humectant in tobacco products, and an additive in concrete mold-release agents and hydraulic fluids.
Viscosity and Hygroscopicity: Storage and Process Notes
The two questions plants new to glycerin ask most often both stem from these physical behaviors.
Viscosity: 99.5% glycerin runs at ~1,400 mPa·s at 20 °C; as temperature drops the value climbs steeply, and around 0 °C flow practically stops. Despite its 18 °C melting point, pure glycerin rarely freezes — it supercools and thickens instead. In winter, keep drums and IBCs in a tempered area before use, and size transfer lines and pumps accordingly for bulk handling. The practical fix is usually simple: let the package rest in a 25–30 °C area before transfer.
Hygroscopicity: A drum left open pulls water from the air and quietly lowers its own purity — which distorts density and viscosity readings and can void food or pharma conformity. The rules are simple:
- Re-seal the package tightly after every use; if a drum is partially used, transfer the remainder into smaller packaging where possible.
- Store away from direct sun and freeze risk; 15–30 °C is the ideal band.
- For long-term bulk storage, a desiccant breather filter on the tank vent preserves purity.
Glycerin is one of the calmest chemicals in terms of flammability and hazard classification; even so, keeping the current SDS on file for every batch should be standard practice in your internal safety system.
Why Documentation Decides Everything in Food Grade
Quality discussions about glycerin are almost never settled by asking "is the product clear?" — clarity is deceptive. The discussion always ends in the paperwork.
On the lot-specific COA, look for: assay (≥ 99.5%), water content, density, color (APHA), ash, chloride/sulfate and — indispensable for pharma and food — the DEG/EG limit test result. Alongside it you should receive the current SDS, a food-contact declaration and, on request, vegetable-origin, halal or kosher certificates.
For export buyers, the document set widens: we prepare SDS and COA in English, provide packing lists and shipment documentation aligned with your customs process, and can supply origin and quality certificates with each consignment. Tell us your destination market at the quotation stage so the paperwork ships with the product, not after it.
The most expensive mistake we see in the field is putting technical-grade glycerin into a food or cosmetic recipe because "it is the same molecule anyway." The cost of the compliance gap exposed at an audit is many times the price difference between grades.
At Yüksek Kimya we share the SDS and lot-specific COA before the order is placed, and our quality system is audited under ISO 9001, ISO 14001, ISO 45001 and GHP certificates — so your purchasing file is complete before the product reaches your warehouse.
Buying Glycerin in Bulk: Packaging, Shipping and Quotation
Glycerin's density of ~1.26 g/cm³ surprises teams used to water: the same package volume weighs noticeably more. Our standard options:
- Jerrycan: 20–25 kg — for trial batches and boutique production.
- Drum (HDPE): 250–260 kg — the most common choice of cosmetic and food producers.
- IBC tote: 1,250–1,300 kg — the best unit cost for regular consumption.
- Bulk tanker: For high-tonnage, continuous-consumption plants.
Glycerin is one of the exceptional products that falls outside dangerous-goods transport classes; even so, our shipments are planned with the same ADR-compliant logistics discipline we apply to hazardous cargo, with standardized labelling and documentation. From our warehouse in Kestel, Bursa we deliver fast across the Marmara region, nationwide on schedule, and we regularly prepare export consignments for international buyers.
For product details and specifications, see our glycerin (glycerol) product page, and browse the rest of your formulation's raw materials in the industrial chemicals and additives category.
To get a quote: Send us your application (cosmetics, food, e-liquid, technical), the grade you need, your one-off or monthly volume and your packaging preference via our contact page or by phone. We respond the same day with a grade-matched sample COA and current pricing — including Incoterms options for export orders.
Related Reading
Frequently Asked Questions
Are glycerin and glycerol the same substance?
Yes. Glycerol is the chemical name of the molecule (propane-1,2,3-triol), while glycerin is the established commercial name. Both refer to the same substance, CAS 56-81-5. Refined 99.5% product is sold under either name; what matters in purchasing is not the name but the purity grade and the document set behind it.
Is there a difference between vegetable and synthetic glycerin?
Chemically they are the identical molecule. The difference is the source and the paperwork: vegetable glycerin comes from plant oils via oleochemical or biodiesel processes, synthetic glycerin from propylene derivatives. E-liquid, cosmetic and vegan/halal/kosher product claims require a vegetable-origin declaration and the certificates that support it.
How do I tell USP glycerin from technical grade?
You cannot tell them apart by eye — both are clear, odorless liquids. The distinction lives in the documents: USP/Ph. Eur. grade is at least 99.5% pure, passes the monograph tests including the diethylene glycol (DEG) and ethylene glycol (EG) limit test, and ships with a lot-specific COA. Technical grade has wider impurity tolerances and may not report these tests at all. For food, cosmetic or pharmaceutical use, always specify USP or food grade.
What determines bulk glycerin pricing?
Glycerin pricing follows the purity grade (technical/USP/food), the source (vegetable/synthetic), packaging type (jerrycan, drum, IBC, bulk), order volume, currency movements and global oleochemical and biodiesel supply. For export orders, Incoterms and destination documentation also shape the landed cost. There is no fixed list price — send us your grade, quantity and packaging needs for a same-day quote.