Hard candy is the oldest process in the supplement factory and the least forgiving. Sugar is boiled until almost no water is left, flavoured, formed and cooled, and the result is a shelf-stable piece that ships cheaply and needs no refrigeration. The catch sits in the middle of that sentence. The cook runs hot enough to destroy a large share of the ingredients a supplement brand wants to put in the product, and no amount of formulation skill later in the line will undo what the kettle did.
In Chinese factory paperwork the category is hard candy (硬质糖果), and it covers lozenges, drops, centre-filled pieces and sugar-free variants. This guide sets out what survives the cook, how forming method drives cost and appearance, why sugar-free changes both the process and the label, and what to check in a manufacturer’s filed scope before you brief a formula.
Hard candy and lozenge are two words for one filing category
Buyers use lozenge when they mean a slow-dissolving piece intended to be held in the mouth, and hard candy when they mean something to suck or crunch. To a Chinese manufacturer both are the same registered category and the same production line. The distinction that does exist is one of size, shape and dissolution profile, all of which are formulation and tooling choices rather than separate regulatory classes.
Where the two words diverge sharply is in the destination market. Lozenge carries regulatory freight that hard candy does not. A piece marketed to soothe a throat, suppress a cough or relieve a symptom is likely to be regulated as a medicinal product rather than a food in the United States, the European Union, the United Kingdom and most of the markets that follow them, with a registration pathway and evidence burden to match. The same physical piece, sold as a flavoured supplement without a symptom claim, generally stays inside the food framework. Decide which side of that line the product sits on before the brief is written, because it determines the claims your artwork may carry and, in some markets, whether a food factory may legally produce it at all.
That decision belongs with the earlier one about which dosage form the product should take. Hard candy competes with three siblings, and each fails in a different place.
The cook is the constraint, and it decides your ingredient list
Hard candy is boiled to what confectioners call the hard-crack stage, typically in the region of 145 to 155 °C, which drives residual moisture down to roughly 1 to 3 per cent. That very low water content is precisely what makes the piece shelf-stable without preservatives. It is also a sustained thermal event, and heat-labile ingredients do not come through it intact.
The practical consequence is a triage exercise on your formula. Minerals, most flavour systems and many botanical extracts tolerate the cook. Vitamin C, most B vitamins, probiotics, enzymes and volatile actives generally do not, or survive so unpredictably that a label claim cannot be built on them. A factory has three honest responses, and it is worth asking which one it proposes:
- Late addition. The active is introduced after the mass has cooled below its degradation threshold, on the cooling table or at the forming step. This works for a narrow band of ingredients and adds a uniformity problem, because the active is being distributed into a stiffening mass rather than a liquid.
- Protection. An encapsulated or coated form of the active is used so the carrier absorbs the thermal load. This raises raw material cost and requires overage, and the encapsulation has to be validated rather than assumed.
- Abandon the form. Some actives simply do not belong in hard candy. A brand that insists usually ends up with a product whose declared potency it cannot defend at end of shelf life.
A manufacturer that answers “no problem” to a heat-sensitive active without naming which of these three routes it will take is not describing a process. Ask for the retention data — the measured percentage of the active remaining in the finished piece, not in the syrup — and treat that number as the basis of your claim. This is the sort of question that belongs in the specification sheet you send the factory, not in a follow-up email after the first sample.
Depositing, die-forming and rope forming set the cost and the look
Once the mass leaves the cooker, three forming routes are common, and the choice shows up in unit cost, minimum tooling investment and what the piece can look like.
| Forming route | What it produces | Tooling | Where it wins |
|---|---|---|---|
| Depositing | Precise shapes, smooth surface, clear or layered pieces, reliable centre fills | Mould-specific, higher initial cost | Branded shapes, premium presentation, liquid or paste centres |
| Die-forming (drop roller) | Traditional balls, discs, ovals, embossed pieces | Roller die, moderate cost | Classic formats at high line speed and lower unit cost |
| Rope forming and cutting | Pillow shapes, striped and layered canes, cut pieces | Lowest, largely line settings | Sampling runs, striped or twisted decorative effects |
Centre-filled pieces deserve a separate note because buyers routinely underestimate them. A liquid or paste centre inside a hard shell is a depositing job, it raises scrap during start-up, and the centre has its own water activity that can migrate into the shell over time and soften it. If the centre is where your active lives — a common way to keep a heat-sensitive ingredient out of the cook — then shell integrity becomes a shelf-life issue rather than a cosmetic one, and stability testing has to run on the assembled piece rather than on the components.
Sugar-free changes the cook, the mouthfeel and the label
Sugar-free hard candy is usually built on isomalt, sometimes on maltitol or a blend. These sugar alcohols behave differently in the kettle: they cook at different temperatures, they are more prone to picking up moisture afterwards, and the finished piece has a distinct cooling sensation that consumers either read as premium or read as odd, depending on the flavour system wrapped around it.
The labelling consequence is concrete and frequently missed. In the European Union, foods containing more than 10 per cent added polyols must carry the statement that excessive consumption may produce laxative effects, under the food information rules in Regulation (EU) No 1169/2011. Most sugar-free hard candies clear that threshold comfortably, so the warning is not an edge case — it is the default, and it needs to be on the artwork before the print run. Other destination markets impose their own variants, so confirm the requirement per market rather than assuming your EU artwork travels.
Sugar-free also interacts with the moisture problem below. Polyol-based pieces are generally more hygroscopic than sucrose-based ones, which makes the wrapper specification a functional decision rather than a decorative one.
Hygroscopicity is why hard candy is individually wrapped
A piece cooked to 1 to 3 per cent moisture sits far below equilibrium with ordinary ambient air, so it spends its entire shelf life trying to absorb water. Left unprotected it develops the defects every confectioner knows by name: a tacky surface, then graining as sugar recrystallises and the piece turns cloudy, then cold flow where pieces deform and stick to each other in the carton. In a humid destination market these can appear within weeks.
The defences are packaging and, secondarily, formulation. Individual wrapping in a flow wrap or twist wrap is standard for a reason. Beyond that, the secondary pack does real work: a foil-laminate pouch or a tin protects a bag of loose pieces far better than a printed paper carton, and a moisture-permeable primary wrapper undermines whatever the outer pack is doing. Where the pieces are sold loose in a jar, a desiccant becomes part of the specification rather than an afterthought. The broader question of how primary and secondary packaging get specified and sourced is covered in the guide to packaging manufacturers in China.
Ask for accelerated stability data on the finished, wrapped piece in the packaging you intend to ship, not on unwrapped samples in a laboratory tray. The two behave nothing alike, and the difference between them is exactly the risk you are trying to price.
Reading the filed scope before you brief a formula
Hard candy is filed separately from every other confectionery format, which means a factory that impresses you on gummies may have no authority to make your lozenge. Three documents settle it, and in each the scope wording matters more than the certificate number.
The export food producer filing, issued by the local customs authority, lists what the site may export. The ISO 9001 and ISO 22000 certificates carry a scope paragraph naming the product categories the management system covers. For United States shipments there is also a food facility registration. Taking Guangci Nutraceuticals in Dongguan as a worked example: its customs filing 4400/11384, issued by Fenggang Customs on 15 July 2022 with long-term validity, names tablet candy, gel candy, hard candy and solid beverage; its ISO 9001:2015 (0070023Q53783R2M) and ISO 22000:2018 (007FSMS1700177) certificates from Zhongjian Certification run to 7 October 2026; and its U.S. FDA food facility registration is No. 17267166330, renewed every two years. That registration is a notification to the agency and nothing more — the FDA does not approve food factories, and a supplier who says it is FDA approved is describing something that does not exist.
What each of those certificates does and does not prove is set out in the comparison of ISO 22000, HACCP and GMP, and the wider assessment routine is covered in auditing a supplement factory in China. On the destination side, entry and labelling requirements are handled in importing dietary supplements from China to the USA. Before any of it begins, the commercial structure — and therefore who owns the formula you are paying to develop — is decided by the distinction between OEM, ODM and private label.
Common questions
What is the difference between a lozenge and a hard candy?
A lozenge and a hard candy are the same registered product category in a Chinese factory filing and are made on the same line, differing only in size, shape and how slowly the piece dissolves. The meaningful difference sits in the destination market, where a lozenge sold with a throat or cough claim is usually regulated as a medicine rather than a food, while the same piece without a symptom claim stays in the food framework.
Which supplement ingredients survive hard candy production?
Minerals, most flavour systems and many botanical extracts tolerate the hard candy cook, while vitamin C, most B vitamins, probiotics and enzymes generally degrade at the 145 to 155 °C required to reach the hard-crack stage. Where a heat-sensitive active is essential, the manufacturer must either add it after cooling, use an encapsulated form, or advise a different dosage form — and should supply retention data for the finished piece.
Why does hard candy turn sticky or cloudy in storage?
Hard candy turns sticky and then cloudy because it is cooked to a residual moisture of roughly 1 to 3 per cent and therefore absorbs water from the surrounding air throughout its shelf life. The surface becomes tacky first, then sugar recrystallises into a grained, opaque appearance, and pieces eventually deform and stick together. Individual wrapping and a barrier secondary pack are the practical defences.
Does sugar-free hard candy need a special warning on the label?
In the European Union, a food containing more than 10 per cent added polyols must state that excessive consumption may produce laxative effects, under Regulation (EU) No 1169/2011. Most sugar-free hard candies built on isomalt or maltitol exceed that threshold, so the statement is normally required rather than optional, and other destination markets apply their own equivalent rules that should be confirmed individually.
Can the same factory make my gummy, tablet and hard candy range?
One factory can hold all of these categories, but each is filed separately and none is implied by another, so the export filing and ISO certificate scope have to name hard candy explicitly. If your range spans several formats, ask for the scope wording covering each one before you place development work, and cross-check it against the gummy, tablet candy and solid beverage requirements for the other products you plan to launch.
Hard candy rewards brands with robust ingredients and a strong flavour proposition, and punishes those who try to force a delicate active through a boiling kettle. Establish what survives the cook, fix the wrapper specification, and confirm the filed scope — those three answers decide whether the programme works.