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Astaxanthin serum OEM/ODM manufacturing
Astaxanthin Serum · OEM/ODM
Astaxanthin is an orange-red, oil-soluble carotenoid made by the single-celled green microalga Haematococcus pluvialis under stress conditions; in cosmetics it usually comes as a microalgae extract (INCI Haematococcus Pluvialis Extract), in which astaxanthin is mostly present as esters. It is often marketed as a "super" antioxidant, but those comparison figures come from chemical measurements in a test tube. The controlled skin-benefit trials with astaxanthin alone all used ORAL capsules, with small samples, and many were company-funded; for topical use we found only open-label studies, combined with oral intake or using multi-ingredient formulas. Astaxanthin is also not a sunscreen, and it degrades with light and oxygen. The Butter-C astaxanthin serum is therefore positioned at the right level: an antioxidant ingredient with a natural orange color in an oil or emulsion base, light-blocking packaging, and skin-conditioning claims tested on the finished product. Haematococcus extract is not currently stocked at the plant, so it is sourced per order, with a COA stating content and method. Butter-C offers turnkey OEM/ODM manufacturing, from formula development and testing to labeled finished goods and the notification dossier.
Formula base
Oil-soluble microalgae extract in a stable oil base
Astaxanthin is highly lipophilic and very poorly soluble in water, so the natural base for the serum is an anhydrous oil or an emulsion with an oil phase. A water-gel serum requires a dispersed form (liposome, cyclodextrin complex, emulsion), which changes the INCI list and needs its own stability testing.
Haematococcus pluvialis extract
INCI Haematococcus Pluvialis Extract (CosIng lists the function as antioxidant); many grades come pre-diluted in a carrier oil, so the label lists the carrier oil INCI as well. Pure astaxanthin is a separate INCI (Astaxanthin, CAS 472-61-7); ask whether it is synthetic or purified.
Stable carrier oils
Squalane, Caprylic/Capric Triglyceride (MCT oil), low in unsaturated components; they dilute the color and slow rancidity of the oil phase. Coco-Caprylate/Caprate helps the oil dry down quickly with less shine (formulation experience).
Protecting the oil phase
Tocopherol is added when the oil phase is blended to protect the carrier oils. We do not market "synergy with vitamin E": laboratory data on astaxanthin–vitamin E synergy are inconsistent.
Emulsion version
A light oil-in-water emulsion (Polyglyceryl-3 Methylglucose Distearate, or Glyceryl Stearate with Cetearyl Alcohol), Glycerin, Phenoxyethanol up to 1% (ASEAN Annex VI) with Ethylhexylglycerin; because it contains water, an ISO 11930 challenge test is mandatory.
Key technical points
Four points specific to a serum named after astaxanthin
Oil serums and antioxidant serums are covered on the general pages; the four items below center on the microalgae extract itself.
Skin-benefit data are mostly oral
Tominaga et al. (2012; first author from a company): an open-label, uncontrolled study, 30 women, 8 weeks, oral 6 mg/day PLUS topical 2 ml of a 78.9 µM solution daily, so the contribution of the topical part cannot be separated; a second study was randomized, double-blind and placebo-controlled, 36 men, oral only. Ito et al. (2018; company-funded, authors are employees): 23 people, oral 4 mg, 10 weeks. Zhou et al. (2021), a systematic review and meta-analysis of 11 studies (9 randomized oral trials, 2 open-label studies of topical or oral-plus-topical use): oral intake improved moisture and elasticity but did not significantly reduce wrinkle depth. Konisky et al. (2023): open-label, 32 women, 12 weeks, a multi-ingredient serum (vitamin C, astaxanthin, fermented turmeric, vitamin E); the results belong to the whole formula, and an author belongs to the company that owns the product. For topical use the evidence is limited; oral results are not turned into benefits of the serum.
Sensitive to light and oxygen
A review by Lima et al. (2021) describes astaxanthin as chemically unstable and cites two figures: free astaxanthin was completely degraded after 21 days of UV exposure, while a cyclodextrin complex retained more than 80%; encapsulated particles retained about 90% after three weeks, more than unencapsulated samples. In practice: add it to the oil phase or the cool-down phase, avoid prolonged heating, limit air entrainment; use light-blocking, airtight packaging; track stability by assaying content, not by color alone.
Content: state how it is calculated
In the alga, astaxanthin is mostly esterified: one analysis found monoesters at 78.8%, diesters at 20.5% and free astaxanthin at only 0.7% of the total, with the extracted proportions varying by solvent (Todorović et al., 2021). The COA must state whether astaxanthin content is calculated as the free form or including esters, the test method, the carrier oil and added antioxidants, heavy metals and microbiology.
Concentration and regulations
There is no CIR report on astaxanthin or Haematococcus pluvialis extract, so no established use concentration exists; among the studies we checked, only one topical study gave a concentration: a 78.9 µM solution (about 47 mg per liter) used together with oral intake. The level in the formula follows the supplier's technical data and stability studies. It is not listed in ASEAN Annexes II, III or VI (June 2026 release), not in Annex VII (UV filters) and not in Annex IV Part 1 (colorants), so it is not used as a colorant and does not provide SPF.
Three formulation directions
Three types of astaxanthin serum
Squalane-based oil serum
Haematococcus extract in squalane and MCT oil, with tocopherol; anhydrous, a few drops in the evening after moisturizer.
Dry-touch oil serum
Adds Coco-Caprylate/Caprate to absorb quickly with less shine, aimed at combination skin and hot, humid climates. A "non-comedogenic" claim is made only after testing on the finished product.
Light emulsion serum
The extract carried in the oil phase of an oil-in-water emulsion with glycerin; feels like a thin lotion, suited to people who dislike oil on the face. The extract is added in the cool-down phase after emulsification.
Packaging is designed with the formula
Dark or frosted glass, airless pump or aluminum tube, little headspace; avoid clear bottles. Clear plastic and rubber dropper bulbs can absorb the orange color, so soak-test them.
Parameters we monitor
What our R&D lab measures on every sample
Below are the parameters Butter-C monitors during formula development and scale-up to production. Specific limits are agreed with you on the approved sample and then written into the product's in-house specification.
- Color & appearance
- Color compared with a reference sample at room temperature, 40°C and under light; gradual fading suggests astaxanthin may have degraded. Watch for rancid odor and clarity.
- Astaxanthin content
- Assayed at the start and at each stability time point, using the same method and the same basis of calculation as the raw material COA.
- Incoming extract
- COA checked for every lot: INCI name, content and basis of calculation (free or total esters), method, carrier oil, added antioxidants, heavy metals, microbiology.
- Peroxide value
- Measured on the oil phase through the stability time points; finished-product limits are set from the formula's own data.
- Color transfer to skin and fabric
- Apply a real-use amount, touch white cotton, towels and cotton pads, then wash-test; the staining level sets the extract level and the label note.
- Stability
- Accelerated aging at 40°C, freeze–thaw cycling and light exposure in the final pack; watch color, content, odor and separation (emulsion version).
- Microbiology
- Tested at a GLP / ISO 17025-accredited laboratory; preservative efficacy (challenge) test per ISO 11930 for the emulsion, and a written microbiological risk assessment per ISO 29621 for the anhydrous oil.
- Irritation & sensitization
- Volunteer testing before the formula is finalized; human data on topical astaxanthin are still scarce.
Claims
Cosmetic-level antioxidant claims, not sun protection
The controlled data on astaxanthin are oral, and the "many times stronger" figures are test-tube measurements. Butter-C reviews the wording on the label and marketing materials as soon as the notification dossier is prepared.
Contains astaxanthin-rich Haematococcus microalgae extract, an antioxidant ingredient
State the INCI names of the extract and the carrier oil. Instead of: "king of antioxidants", "super antioxidant", "many times stronger than vitamin C".
Helps skin look fresh, soft and smooth
Requires testing on the finished product. Instead of: anti-aging, wrinkle erasing, collagen boosting; the moisture and elasticity results of oral capsule trials.
Natural orange color from astaxanthin
Be honest about the color and possible staining. Instead of: using astaxanthin as a colorant for the product.
Use with sunscreen during the day
Astaxanthin is not a UV filter (not in ASEAN Annex VII). Instead of: sun protection, boosting SPF, protecting skin from UV, "sun protection from within".
Label reminders
May leave an orange tint on skin and fabric; test on a small area of skin before use; avoid the eye area; stop if redness or itching occurs. Store in a cool place away from light. Instead of: "non-irritating".
Pregnancy and breastfeeding
Not enough data for topical use; the product is not marketed to this group, and our advice is to ask a doctor.
Manufacturing specifications
Our capabilities
- Texture
- Anhydrous oil serum or light emulsion; yellow-orange to orange-red depending on the extract level.
- Pack formats
- Dark glass dropper bottle, airless pump or aluminum tube. Volume agreed when selecting packaging.
- Extract sourcing
- Not stocked at the plant; sourced per order, with a COA stating content and method required for every lot.
- Minimum order quantity
- Agreed per order, depending on the raw material, formula direction and pack format.
- Testing
- Performed at a GLP / ISO 17025-accredited laboratory, including an astaxanthin assay; certificate of analysis delivered with every lot.
- Documentation
- Product Information File (PIF) and cosmetic product notification dossier prepared by Butter-C, with an extract COA stating content, basis of calculation and carrier oil.
- Packaging
- Label design, printing and packing run in parallel with formula development.
Suggested product concept
Evening astaxanthin oil serum
A product direction to help you picture the concept, not a ready-made product for sale. The actual formula is developed to fit your brand's positioning and price range.
Haematococcus pluvialis extract
The named ingredient; the level follows technical data and is finalized by color-transfer testing and a stability study with assays.
Squalane, MCT oil
Stable, light, low-odor carrier oils, the basis for a softening claim.
Tocopherol
Protects the oil phase from oxidation; no synergy claims.
30 ml dark glass bottle
Light-blocking, with dropper; the label notes the color, a small-area test and daytime sunscreen use.
Customization options
What you can specify
The same product type can be aimed at very different customers. Tell us your requirements in the areas below and our pharmacists will develop a matching formula.
Raw material form
Oil-type Haematococcus extract (most common), astaxanthin as a separate INCI, or a water-dispersible form for a gel serum; a dispersed form changes the carrier INCI list and needs its own stability testing.
Texture
Oil serum, dry-touch oil or light emulsion.
Color depth
The extract level decides the color and how much it stains; finalized by color-transfer testing on the actual formula.
Fragrance
We recommend fragrance-free; the microalgae extract and carrier oils have a faint odor of their own.
Ingredient positioning
Fragrance-free, silicone-free, vegan; microalgae extract has no animal origin, and a vegan claim is assessed on the whole formula and the supplier's statement.
Packaging
Dark glass dropper, airless pump or aluminum tube, which sets the level of light and air protection.
Further reading
Related knowledge
Astaxanthin and Haematococcus microalgae extract in cosmetics
Oral and topical evidence, light stability, color, why it is not a sunscreen, and regulations (in Vietnamese).
Vitamin C serum OEM/ODM manufacturing
The general page on water-soluble antioxidant serums, with a different form, pH and stabilization approach.
Gac fruit facial oil OEM/ODM manufacturing
Another carotenoid-rich oil with the same color, light and oxidation challenges; the data are not shared.
Vitamin E (tocopherol) in cosmetics
The antioxidant that protects the oil phase alongside the extract (in Vietnamese).
SPF: meaning and testing
SPF comes only from permitted UV filters and testing on the finished product (in Vietnamese).
How we work
From idea to finished batch
Eight steps and three milestones signed off by both sides: approved sample, notification number, finished batch. Step-by-step details (in Vietnamese) →
Get started
Tell us about the product you plan to launch
Send us your product direction and expected volume. Our team will get back to you during business hours (Vietnam time, GMT+7).
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