Stickiness is a frequent consumer complaint and a persistent packaging problem for gummy supplement makers, yet there is no universal standard for measuring it. Adhesiveness is a complex property that doesn't lend itself to a single, simple test. Unlike hardness, which a texture analyzer measures with a standard compression test, or moisture content, which has established analytical methods, stickiness depends on several interacting variables. These include the gummy's surface tack, its internal cohesiveness, the ambient temperature and humidity, and the specific materials the gummy contacts (fingers, packaging, storage containers). Most stickiness starts with moisture. Gummies contain humectants such as glycerin and sorbitol, which pull water from humid air, and citric acid can react with that surface moisture to form a tacky film.
A standardized test would require agreeing on all these variables, which is difficult across different manufacturing environments. At KorNutra, we take a practical approach: we don't chase a hypothetical universal standard. Instead, we focus on strong, empirically driven in-process controls to ensure our gummies meet the consistently low-stickiness performance our customers expect. Our team evaluates adhesiveness through validated internal methods that control for:
- Temperature and humidity: We test gummies under both ambient and accelerated storage conditions.
- Surface contact: We measure adhesion to common packaging films and to human touch (using tactile evaluations).
- Time after production: We track stickiness changes during curing and shelf life.
Why no universal standard exists
The food and supplement industries have not coalesced around a single stickiness test for three reasons:
- Diverse formulations: Gummy recipes vary widely. Different gelatin ratios, pectin types, starches, and sugar alcohols all affect adhesiveness. A test valid for one formulation may not transfer to another.
- Conflicting priorities: Manufacturers need low stickiness so pieces move through filling lines without fusing, while consumers read an overly dry gummy as stale. Balancing softness against surface tack leaves no industry consensus on what counts as acceptable.
- Measurement complexity: Adhesiveness is not a single metric. It involves tack (instant stickiness), peel strength (force to remove a gummy from a surface), and cohesiveness (how strongly the gummy holds itself together). Each requires different test equipment and conditions.
Related standards exist, but they don't transfer. ASTM D2979, a probe tack method for pressure-sensitive adhesives, was withdrawn in 2019 and was never written for edible gels, so supplement manufacturers rely on their own validated methods.
What this means for you
When choosing a gummy supplement manufacturer, avoid those who cite a generic standard for stickiness. Instead, ask for specific data: internal test results under defined conditions, stability data showing stickiness over shelf life, and packaging compatibility tests. At KorNutra, we provide this information transparently, because we know that consistent, non-sticky gummies are a mark of quality.
Surface tack is not the same as blocking
Most consumers who complain about sticky gummies are describing two different failures. Surface tack is what you feel when a single gummy clings to your fingers. Blocking is what happens when gummies fuse to each other and to the inside of the bottle, arriving as one solid clump. A gummy can pass a tack test on the bench and still block in a bottle after a summer in a hot warehouse, because heat and humidity soften the surface and let pieces weld together under their own weight.
If you are evaluating a manufacturer, ask for data on both. Tack measurements cover the finger-feel problem. For blocking, you want packaging compatibility tests and shipping simulations: gummies held in their finished bottle or pouch under accelerated heat and humidity, then inspected for fusion. A manufacturer that only tests tack is missing the failure most consumers complain about.
In short, the lack of a universal standard reflects the complexity of gummy manufacturing. The best solution is a manufacturer with rigorous, validated internal methods, and that's exactly what KorNutra delivers.