How do merchants evaluate the stability of their brand's skincare products

Merchants need to scientifically verify the stability of skincare products from multiple dimensions such as formula, process, and storage. The following is a systematic evaluation framework and practical methods:

1、 Formula stability assessment

Component compatibility testing

Detection objective: To avoid oxidation, hydrolysis, precipitation and other reactions between components.

method:

Accelerated test: Place the sample in an environment with a temperature of 40 ℃± 2 ℃ and a humidity of 75% ± 5% for 3 months, and observe whether there is layering, discoloration, or odor.

PH monitoring: Use a pH meter to detect the pH value of the formula and ensure its stability during storage (such as the common pH range of 4.5-7.5 for skincare products).

Component analysis: Compare the changes in the content of active ingredients (such as VC and peptides) before and after storage using instruments such as high-performance liquid chromatography (HPLC) and gas chromatography (GC).

Effectiveness of anti-corrosion system

Microbial challenge test: Inoculate standard bacterial solution (such as Escherichia coli, Staphylococcus aureus) into the sample, culture at 25 ° C for 14 days, and test whether the colony count meets the requirements of the "Cosmetic Safety Technical Specification" (generally, the antibacterial rate should be ≥ 90% within 72 hours).

2、 Physical stability assessment

Texture and appearance inspection

Sensory evaluation: Observe whether the sample has stratification, agglomeration, demulsification (such as lotion becoming water), viscosity change (such as paste becoming thin), and can be quantitatively detected with the help of a viscometer (such as a rotary viscometer).

Particle size distribution: use laser particle size analyzer to analyze the particle size and uniformity of lotion, essence and other products. The more uniform the particle size, the higher the stability.

Temperature resistance test

Cold and hot cycle test: Store the sample in a cyclic manner between -15 ℃ and 50 ℃ (e.g. -15 ℃ for 24 hours → 25 ℃ for 24 hours → 50 ℃ for 24 hours), repeat 3-5 times, and observe whether there is water separation, thickening, or other phenomena.

3、 Packaging and Storage Impact Assessment

Compatibility of packaging materials

Migration testing: Load the product into an actual packaging container, seal it, and store it for 3 months. Check whether the packaging materials (such as plastic bottles, hoses) release harmful substances (such as plasticizers) or react with the contents (which can be detected by gas chromatography-mass spectrometry (GC-MS)).

Sealing test: Confirm whether the packaging container is leaking air through vacuum attenuation method or pressure test to avoid air and moisture infiltration that may cause product deterioration.

Storage condition simulation

Long term stability test: Store the sample in an environment of 25 ℃± 2 ℃ and 60% ± 5% humidity for 6-12 months, regularly (such as monthly) test various indicators (composition, texture, microorganisms), compare with accelerated test results, and verify the actual shelf life.

4、 Production process and batch stability

Process repeatability verification

Simulate the mass production process on the production line, compare the viscosity, pH value, and active ingredient content of different batches of products to ensure process stability (such as the influence of emulsification temperature and stirring speed on quality).

Batch consistency testing

Randomly select 3 or more batches of products for comprehensive stability testing (ingredients, microorganisms, physical properties), and the data fluctuation range should be controlled within 5% -10% (if the deviation of active ingredient content is ≤ 5%).

5、 Compliance with regulations and standards

Reference standards: Follow the "Technical Specification for Safety of Cosmetics" and "GB/T 35833-2018 Methods for Stability Testing of Cosmetics" to ensure that the testing methods and results comply with industry standards.

Sample observation: Retain samples for at least 3 years for each batch of products, conduct regular re inspections, and track long-term stability (such as changes in color and odor during the shelf life).

6、 Consumer feedback and market validation

Conduct small-scale trial testing before product launch, collect user feedback on the quality and shelf life of the product (such as whether there are allergies or spoilage), and optimize the formula based on laboratory data.

Summary: Evaluation Process Suggestions

R&D stage: formula screening+accelerated testing+component analysis;

Pilot stage: process validation+packaging compatibility+microbial challenge;

Mass production stage: batch stability+long-term sample retention+market tracking.

Through the multidimensional evaluation above, the risk of product deterioration can be systematically reduced, ensuring quality stability during the shelf life.