How handmade soap is made, and why it changes after cutting
Handmade soap is made in three ways, and each has its own weak points:
- Cold process. Oils such as coconut, olive or palm are mixed with sodium hydroxide solution, poured into moulds, cut into bars and left to cure for several weeks. During curing, water evaporates and the bar loses weight and hardens. Bars packed too early are soft, heavy at packing and light on arrival.
- Hot process. The same mix is cooked until the reaction is complete, then packed into moulds. Curing is shorter, but the surface is rougher and harder to keep uniform.
- Melt and pour. A ready-made glycerin base is melted, coloured, scented and poured. Many bases contain synthetic detergents, which matters for how the product is classed in the US.
In India, soap is a cosmetic under the Cosmetics Rules, 2020, so the maker needs a cosmetics manufacturing licence. The Rules' Ninth Schedule ties toilet soap (IS 2888), transparent toilet soap (IS 11303) and bathing bars (IS 13498) to Indian Standards. Herbs, clays, charcoal and essential oils are added for colour and scent, and each one can bleed, speckle or shorten shelf life.
Soap or cosmetic: the label decides the rulebook
| Market | Rule | What it means for a bar |
|---|---|---|
| United States | 21 CFR 701.20 | A bar is "soap", outside the cosmetic definition, only if most of its non-volatile matter is alkali salts of fatty acids, its cleaning comes from those salts, and it is labelled and sold only as soap. Such true soap is regulated by the CPSC |
| United States | FDA intended use | A claim such as moisturising or deodorising makes the bar a cosmetic, with full cosmetic labelling. Antibacterial or acne claims make it a drug. Detergent-based bars are cosmetics even if called soap |
| United States | CPSC children's products | A soap made mainly for children 12 and under needs a tracking label, third-party lead testing and a Children's Product Certificate; see CPSIA |
| EU | Regulation 1223/2009 | Toilet soaps are named among cosmetic products in the Regulation's recitals. Every bar needs an EU responsible person, a safety report, CPNP notification and Article 19 labelling, including the ingredient list and nominal weight |
| Great Britain | UK cosmetics rules | Notification through the UK's Submit Cosmetic Product Notifications service and a UK responsible person's address on the pack |
So one artwork rarely fits both markets. A bar labelled "nourishing shea soap" is a cosmetic in the US as well as the EU. The CPSC also notes that cosmetic ingredients alone may bring a bar under FDA. The inspector reads every claim on the wrapper against the version approved for the market on the order.
What we check on handmade soap
| Check | How it is checked | What fails |
|---|---|---|
| Bar weight | Unwrapped and wrapped bars weighed on a calibrated scale; cutting date recorded to judge remaining loss | Below the declared weight, or so close to it that further curing will take it under |
| Cure and hardness | Thumb pressure and edge test; days since cutting checked against the agreed cure | Soft bars, bars packed before the agreed cure time |
| Cross-section | One sampled bar cut through | White pockets or liquid spots (possible unreacted lye), air holes, unmixed colour |
| Surface | Bars inspected under light | Beads of moisture (sweating), white soda ash, cracks, orange spots |
| Odour | Against the retained sample | Rancid or crayon-like odour, scent faded |
| Shape and stamp | Size with a calliper; logo stamp against the sample | Uneven cutting, chipped corners, blurred stamp |
| Wrapping | Shrink film, paper band or box; seal and fit | Open seals, film wrinkled over the label, box crushed |
| Labels and codes | Claims, ingredient names, weight, batch code, origin and responsible person against artwork for each market | Unapproved claims, missing batch code, wrong market address |
Common handmade soap defects and how they are classed
| Defect | Typical cause | Class |
|---|---|---|
| Pockets of unreacted lye in the bar | Poor mixing or wrong weighing of the lye | Critical |
| Treatment claim on the wrapper, such as "cures eczema" | Marketing copy not checked per market | Critical |
| Orange rancid spots | Oxidised oils, too much unsaturated oil, heat | Major |
| Short weight | Packed before curing finished; no allowance for loss | Major |
| Sweating or wet wrappers | Glycerin drawing moisture in humid storage | Major |
| Cracked or broken bars | Overheating in the mould, rough handling | Major |
| Soda ash on the surface | Air contact during early curing | Minor |
| Faint or off-centre stamp | Stamping too late or unevenly | Minor |
Your defect list decides the final class. Free alkali, pH and microbiology are measured by an accredited lab on bars we seal; see lab testing coordination.
Packing, transit and your purchase order
Soap reacts to its surroundings. Bars sealed tight in film while still curing sweat and stay soft; bars packed loose in a humid monsoon warehouse pick up moisture; bars in a hot container lose scent and can spot. Heavy cartons crush the bottom layer of boxed soap. The inspector checks that bars were cured for the agreed time before wrapping, that cartons are dry and not overfilled, and that pallets are not stacked beyond the carton's strength.
Put these in your purchase order:
- Method (cold, hot or melt and pour) and the oil blend.
- Minimum cure time before wrapping, and weight at packing including a loss allowance.
- Declared net weight and tolerance, and how it is printed for each market.
- Approved claims per market; ingredient list approved by your safety assessor.
- Fragrance or essential oil, with its IFRA certificate and safety data sheet.
- Wrapping type and carton spec; batch code format.
- The lab, the tests and the number of sealed bars per batch.
Soaps scented with essential oils share risks with essential oil orders. Book an inspection.