Creams: SOP for Mixing Techniques for Cream Formulations – V 2.0

Standard Operating Procedure for Mixing Techniques for Cream Formulations

Department	Creams
SOP No.	SOP/CRM/046/2025
Supersedes	SOP/CRM/046/2022
Page No.	Page 1 of 6
Issue Date	13/10/2025
Effective Date	18/10/2025
Review Date	13/10/2026

1. Purpose

The purpose of this Standard Operating Procedure (SOP) is to define the mixing techniques required to prepare cream formulations effectively. Proper mixing is critical for achieving uniformity, consistency, and stability in the final cream product. This SOP ensures that mixing is done according to the formulation requirements, preventing defects such as separation, clumping, or inadequate dispersion of active ingredients.

2. Scope

This SOP applies to all cream formulations in the Creams Department that require mixing of ingredients. It covers the procedures for mixing raw materials, including both active and inactive ingredients, ensuring homogeneity in the final cream product.

3. Responsibilities

Formulation Development Team: Responsible for determining the mixing method, time, and equipment necessary to achieve the desired consistency and texture in the final cream formulation.
Quality Control (QC): Responsible for monitoring the mixing process to ensure consistency, viscosity, and uniformity in the final product.
Quality Assurance (QA): Ensures compliance with this SOP and verifies that the mixing process meets the regulatory and quality standards outlined in the Master Formula Record (MFR).
Production Team: Responsible for carrying out the mixing procedure according to the MFR and ensuring that the mixing parameters are strictly followed.

4. Accountability

The Head of Creams Manufacturing is responsible for overseeing the mixing process. The QA Manager is accountable for ensuring compliance with this SOP and verifying that the final product meets the required quality standards before it moves to the next stage of production.

5. Procedure

5.1 Preparation of Ingredients

Confirm that all ingredients for the cream formulation are available, properly weighed, and ready for mixing. This includes raw materials, emulsifiers, active ingredients, preservatives, and any additional additives required by the formulation.
Ensure that all ingredients are within their specified shelf life and meet the quality standards outlined in the Master Formula Record (MFR).
Inspect the ingredients for contamination, improper packaging, or any other issues that could affect the quality of the cream. Any non-compliant ingredient should be rejected and replaced.

5.2 Preparation of Mixing Equipment

Ensure that all mixing equipment, such as mixers, blenders, and homogenizers, are properly cleaned and calibrated according to the equipment maintenance SOPs.
Verify that the mixing vessel is the correct size for the batch and that it is free from contaminants.
Set up the equipment to the desired speed and mixing settings, as specified in the MFR, to achieve the desired consistency for the cream.

5.3 Initial Mixing of Ingredients

Begin mixing the primary ingredients, such as water phase and oil phase components, to form the cream base. Start mixing at a low speed to prevent splashing and to ensure even distribution of ingredients.
Gradually increase the mixing speed to the required level to allow the components to blend thoroughly. Ensure that the water phase and oil phase are emulsified uniformly.
Use a high-shear mixer or homogenizer for mixing if the formulation requires a more intensive blend to achieve fine emulsions and particle sizes.
Continue mixing until a smooth, homogeneous mixture is achieved with no visible separation or clumping.

5.4 Addition of Active Ingredients

If active ingredients are part of the formulation, add them at the appropriate stage, typically after the emulsification process, when the mixture has cooled to the required temperature (usually below 40°C to avoid degradation of heat-sensitive ingredients).
Add the active ingredients slowly while maintaining continuous mixing to ensure that they are evenly distributed throughout the mixture.
If any active ingredients are sensitive to light, oxygen, or temperature, ensure that they are added in an inert environment or under controlled conditions to preserve their potency.
Ensure that each active ingredient is fully incorporated before adding the next ingredient.

5.5 Homogenization (If Required)

After the active ingredients have been added, if necessary, use a homogenizer to further refine the mixture and ensure uniform dispersion of ingredients. This step helps reduce the particle size and increases the cream’s stability.
Set the homogenizer to the recommended pressure and speed to achieve optimal consistency and stability in the cream.
Continue homogenization until the cream reaches the desired particle size, typically below 5 microns for a smooth, uniform texture.

5.6 Final Mixing and Viscosity Adjustment

After homogenization, conduct a final mixing step to ensure that the cream is fully uniform and all ingredients are evenly incorporated.
If necessary, adjust the viscosity of the cream by adding thickeners or modifying the mixing time or speed. The final viscosity should meet the specification outlined in the MFR.
Perform a visual inspection to ensure that the cream is free from lumps, separation, or air pockets.

5.7 Quality Control Testing

Once the cream has been mixed, conduct the following quality control tests to ensure that the product meets the required standards:
- Viscosity: Measure the viscosity to ensure the desired texture and consistency.
- pH: Test the pH of the cream to ensure it falls within the specified range (typically 4.5 to 6.5).
- Microbial Testing: Perform tests to ensure that the cream is free from microbial contamination.
- Particle Size: Measure the particle size to confirm the emulsion is uniform and within specification.
If the cream passes all quality control tests, it is approved for further processing or packaging. If any issues are identified, corrective actions should be taken, and the batch may need to be reprocessed.

5.8 Documentation and Reporting

Record all mixing parameters, including ingredient quantities, mixing times, speeds, and any adjustments made during the process.
Document the results of quality control tests, including viscosity, pH, and particle size measurements, in the batch record.
The batch record and test results must be submitted to the QA team for review and approval before moving forward with packaging or further processing.

5.9 Final Approval and Use of Mixed Cream

Once the cream passes all quality control checks and the batch record is approved by QA, the cream is ready for further processing, such as packaging or filling.
Ensure that all records related to the mixing process are properly filed and retained for future reference and regulatory compliance.

6. Abbreviations

QC: Quality Control
QA: Quality Assurance
GMP: Good Manufacturing Practices
API: Active Pharmaceutical Ingredient
MFR: Master Formula Record

7. Documents

Mixing Log (Annexure-1)
Batch Record (Annexure-2)
Quality Control Test Report (Annexure-3)

8. References

Good Manufacturing Practices (GMP) Guidelines – 21 CFR Part 211
International Conference on Harmonisation (ICH) Q7 – Good Manufacturing Practice for Active Pharmaceutical Ingredients
FDA Guidelines for Cosmetics Manufacturing

9. SOP Version

Version: 2.0

10. Approval Section

	Prepared By	Checked By	Approved By
Signature
Date
Name
Designation
Department

11. Annexures

Annexure-1: Mixing Log

Batch Number	Process Step	Time	Operator
12345	Initial Mixing	09:00 AM	John Doe

Annexure-2: Batch Record

Batch Number	Process Step	Time	Operator
12345	Mixing	09:30 AM	Jane Smith

Annexure-3: Quality Control Test Report

Test Parameter	Result	Specification	Remarks
Viscosity	3200 cP	3000-3500 cP	Pass
pH	5.8	4.5-6.5	Pass

Revision History:

Revision Date	Revision No.	Revision Details	Reason for Revision	Approved By
01/03/2024	1.0	Initial Version	New SOP Creation	QA Head
01/03/2025	2.0	Format Revision and Updates	Standardization of Document	QA Head