Corn Starch is a plant-derived polysaccharide powder (granular amylose + amylopectin) that balances sensory modification, sebum/moisture management, and filler/binder duties across leave-on, rinse-off, and powder formats.
Performance depends on botanical source, particle size distribution, residual moisture, lipid/protein impurities, and—most decisively—whether the starch is native, pregelatinized, or chemically modified, because those parameters govern oil uptake, rub-out, and dispersibility.
Product Description: Porous, plant-sourced granules sequester oil and moisture via capillary uptake and surface adsorption, delivering sebum control, mattifying after-feel, and a soft-focus finish when blended into lotions, body powders, dry shampoos, deodorant sticks, and color cosmetics while replacing micas or silicas for cost-effective matte filling.
High surface area and capillary porosity also improve powder flow, reduce clumping in bath/dusting powders, and modestly support interparticulate binding in pressed or compacted pigments when partnered with stearates, esters, or silicone binders; choose PSD and morphological profile to balance drag, whitening, and optical scattering.
Native starch is not ready for cold-water gels unless wetted with pregelatinized or crosslinked grades; dispersing via high-shear slurries or pre-wetted esters avoids grit or sedimentation, while heat (≥60°C) triggers gelatinization, retrogradation, and microbiological risk, so consider modified starches (pregelatinized, hydroxypropyl starch phosphate, aluminum starch octenylsuccinate) when you need stronger cold-process handling or oil-phase dry-touch.
Bioburden and rheology interactions must be managed because starch can weaken polymer networks, increase yield stress, and support microbial growth in high-water systems; keep incoming powder clean, challenge-test preservation, and track viscosity across temperature cycling to catch thixotropy shifts.
Usage: Suitable for mattifying emulsions, body powders, pressed/loose color cosmetics, deodorant sticks or creams, and dry shampoos where oil absorption, dry-touch, or filler duties are required while keeping drag and sheen low.
Mixing method:
- Pre-disperse in oil, ester, or glycol carriers to wet the granules before folding into the main batch and prevent dry clumps.
- When adding to water-heavy phases, build a high-shear slurry or micronize under agitation so the powder stays suspended and does not swell into grit.
- Sprinkle into dry blends (powders, blushes, dry shampoos) under controlled humidity, and pair with other flow aids to offset moisture pickup.
Usage rate: 0.5–30%
This range spans matte leave-on systems (0.5–5%), deodorant/cream sticks (2–15%), pressed or loose powders (2–30%+, especially in talc-free strategies), and dry shampoo blends (10–60% when used with silica/other starches); test stability when approaching the upper bound to avoid whitening or viscosity collapse.
Product characteristics: Fine, off-white to pale straw powder with a silky-dry feel that flows freely yet remains hygroscopic; naturally derived and sparkle-free.
Solubility: Hydrophilic granules that do not dissolve but disperse in water or glycols with agitation (heat gelatinizes the starch and can change viscosity/retrogradation behavior), while oil-phase integration requires pre-wetting in esters or emollients; insoluble in hydrocarbons but can suspend when blended as a dispersion.
Store in a tightly sealed dry container to minimize clumping and microbial risk; confirm incoming powder meets microbial and PSD specs before loading.
