Face Serum Manufacturing in India: A Specification Guide
A serum is sold on its actives, and most of the ones that matter are unstable. Active level, pH, stability and packaging decide whether the product still works when the consumer opens it.
What Makes a Serum Different
This guide is for brand owners developing face serums in India.
A serum is a leave-on cosmetic with a higher active concentration than a typical cream, and a lighter base designed for absorption. The entire proposition rests on the actives, which means the formulation questions are different from those for a moisturiser.
Most popular serum actives are difficult to formulate. Vitamin C derivatives oxidise, retinoid-type ingredients degrade with light and air, and acid-based actives require a specific pH to function and an appropriate level to remain tolerable. Niacinamide is more stable but has its own interaction and pH considerations.
The result is that a serum which looked fine on day one can be substantially degraded by the time a consumer finishes the bottle, and nothing on the label would reveal it. This is a stability and packaging problem as much as a formulation one.
Specification Points
What belongs in your brief.
| Element | What to Specify |
|---|---|
| Active and its form | The exact ingredient, not a category name |
| Active level | Percentage, with professional advice on tolerability |
| pH | Target range, since many actives are pH-dependent |
| Base type | Aqueous, serum gel, emulsion or anhydrous |
| Preservative system | With efficacy testing |
| Viscosity and texture | Approved against a physical sample |
| Colour at manufacture | With acceptable drift range over shelf life |
| Antioxidant or chelator system | Where the active requires it |
| Packaging | Light and air protection as the active requires |
| Fill volume | With overfill considered for airless systems |
| Stability protocol | Including real-time, accelerated and light exposure |
| Microbial and heavy metal limits | Per batch |
Specifying the exact active form matters. Vitamin C, for instance, exists in several forms with very different stability characteristics, and a brief saying only vitamin C leaves the formulator to choose.
Packaging Decides Outcomes
Possibly the most consequential choice.
Airless Pump
Limits air exposure across use, which matters for oxidation-prone actives. More expensive, and fill and dispensing need testing.
Dropper Bottle
Common and attractive, but introduces air on every use. Suitable for more stable actives, less so for oxidation-prone ones.
Opaque or Amber
Needed where the active is light-sensitive. A clear bottle showcasing colour may be actively harming the product.
Material Compatibility
Required, since actives can interact with packaging components. Test the formulation in the actual pack.
A clear glass dropper bottle is the most common serum format and the least protective. Where your active is oxidation or light sensitive, that choice has a cost in product performance that will show up as consumer complaints about colour change.
Stability and Colour Drift
Plan for it and define it.
- Require real-time stability at a defined temperature and humidity for the intended shelf life.
- Require accelerated stability for early signals.
- Require temperature cycling, given Indian conditions and transport.
- Require light exposure testing where the active is light-sensitive.
- Require active assay at each time point, not just appearance.
- Define acceptable colour drift and test against it.
- Require preservative efficacy testing.
- Test the formulation in the actual final packaging.
- Set shelf life from the data, including the active assay results.
- Consider a period-after-opening statement where appropriate.
Many serum actives darken as they degrade, and that colour change is the single most common consumer complaint in this category. Consumers interpret it as the product going bad, which is broadly correct.
Claim Limits
These are cosmetics.
Available: appearance claims about brightness, texture, evenness of tone, hydration and the look of fine lines, where substantiated for your product.
Not available: treating acne, pigmentation disorders, or any skin condition; reversing ageing; or any claim implying a physiological change beyond appearance. These are the claims serum marketing most often reaches for.
Active percentage claims on the front of pack must be accurate for the actual formulation and should be read alongside stability data, because a declared percentage that degrades over shelf life creates an accuracy problem. If you declare a percentage, substantiate that it is present through shelf life.
Clinical-sounding claims require actual substantiation. Before-and-after imagery, percentage improvement figures and claims of visible results in a stated timeframe all need study support and professional advice on permitted wording.
Development Checklist
Complete before commercial production.
- Specify the exact active and its form, not a category name.
- Obtain professional advice on active level and tolerability.
- Specify target pH range.
- Confirm active compatibility with other ingredients.
- Specify antioxidant or chelator system where required.
- Choose packaging appropriate to the active’s sensitivities.
- Run packaging material compatibility testing.
- Require real-time, accelerated, cycling and light stability data.
- Require active assay at each stability time point.
- Define acceptable colour drift.
- Require preservative efficacy testing.
- Verify the manufacturer’s cosmetic licence covers the product.
- Take professional advice on safety assessment requirements.
- Substantiate any declared active percentage through shelf life.
- Write a claim set limited to appearance claims.
- Obtain substantiation before any clinical-sounding claim.
Developing a Serum Range?
Share your target actives, pack preference and volume and our team will respond with formulation options and documentation.
Frequently Asked Questions
Why are serum actives difficult to formulate?
Because most popular ones are unstable. Vitamin C derivatives oxidise, retinoid-type ingredients degrade with light and air, and acid-based actives need a specific pH to function and an appropriate level to stay tolerable. A serum fine on day one can be substantially degraded later.
Does packaging really matter that much?
Yes. A clear glass dropper bottle is the most common serum format and the least protective, introducing air on every use. Where your active is oxidation or light sensitive, that choice costs product performance and generates colour-change complaints.
What should stability testing include?
Real-time at defined conditions, accelerated, temperature cycling for Indian conditions, light exposure where relevant, and active assay at each time point rather than appearance alone. Test in the actual final packaging.
Can I claim a serum treats pigmentation or acne?
No. Treating any skin condition is outside cosmetic claims. Appearance claims about brightness, texture, evenness of tone and the look of fine lines are available where substantiated for your product.
Can I put the active percentage on the front of pack?
Only if it is accurate for the actual formulation and you can substantiate that it remains present through shelf life. A declared percentage that degrades over the shelf life creates an accuracy problem.