the required specifications. QC also monitors the adjustments made during production.

Quality Assurance (QA): Ensures that the viscosity adjustment process is performed according to this SOP and that all adjustments are properly documented.

Production Team: Responsible for performing the viscosity adjustment and ensuring that all equipment and materials are used according to the SOP and the MFR.

4. Accountability

The Head of Creams Manufacturing is responsible for ensuring that viscosity adjustments are performed correctly and that the final product meets the required specifications. The QA Manager is accountable for ensuring compliance with this SOP and verifying the final viscosity of the cream.

5. Procedure

5.1 Preparation of Ingredients and Equipment

1. Ensure that all ingredients for viscosity adjustment, such as thickeners, stabilizers, or rheology modifiers, are available and within specification.
2. Prepare all mixing and measuring equipment, such as viscometers, mixers, and homogenizers. Ensure they are clean and calibrated according to the equipment maintenance SOP.
3. Verify that the raw material and cream formulations meet the quality standards before proceeding with viscosity adjustment.

5.2 Viscosity Measurement

1. Measure the viscosity of the cream using an appropriate viscometer (e.g., Brookfield viscometer or rheometer). Take a representative sample of the cream formulation from the mixing vessel or after the homogenization step.
2. Record the viscosity reading in the batch record, noting the time, temperature, and any specific observations during the measurement.
3. Compare the measured viscosity with the target viscosity specified in the MFR. If the viscosity is within the acceptable range, proceed to the next stage of manufacturing. If the viscosity is too high or too low, proceed with the adjustment process.

5.3 Viscosity Adjustment

1. If the viscosity is too low (i.e., the cream is too thin), gradually add viscosity-enhancing agents, such as gums (e.g., xanthan gum, guar gum), synthetic thickeners, or hydrocolloids, depending on the formulation requirements.
2. If the viscosity is too high (i.e., the cream is too thick), reduce the viscosity by adding diluents or adjusting the mixing speed and time to reduce the shear force.
3. Add the viscosity-adjusting agents gradually and mix thoroughly to ensure uniform distribution. Allow the cream to mix for an adequate amount of time to ensure the agents are fully hydrated and incorporated.
4. Monitor the viscosity throughout the adjustment process to ensure that it is brought within the desired range.

5.4 Post-Adjustment Viscosity Check

1. After adjusting the viscosity, measure the viscosity again using the same method and equipment as before to verify that the cream now falls within the specified viscosity range.
2. Record the final viscosity reading in the batch record, along with the details of any adjustments made, such as the amount and type of thickening agents added.
3. If the viscosity is still outside the specified range after adjustment, repeat the adjustment process until the desired viscosity is achieved.

5.5 Final Quality Control Testing

1. Once the desired viscosity is achieved, perform additional quality control tests to ensure the cream meets all other required specifications, including pH, texture, and stability.
2. If the cream passes all required tests, it is approved for the next stage of production, such as packaging or further processing.
3. Document all quality control test results and corrective actions taken during viscosity adjustments in the batch record.

5.6 Documentation and Reporting

1. Document all viscosity measurements, adjustments, and test results in the batch record. This includes the initial and final viscosity readings, the amount of viscosity-adjusting agents used, and any corrective actions taken.
2. Submit the batch record for review and approval by the QA team before proceeding with the final steps of production.

5.7 Final Approval and Use of Cream

1. Once the cream meets all the required viscosity specifications and has passed all quality control tests, it is ready for the next stage of manufacturing, such as filling and packaging.
2. Ensure that all records related to viscosity adjustments 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

1. Viscosity Adjustment Log (Annexure-1)
2. Batch Record (Annexure-2)
3. 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: Viscosity Adjustment Log

Batch Number	Initial Viscosity	Adjustment Method	Final Viscosity	Remarks
12345	1500 cP	Added 0.5% xanthan gum	2000 cP	Viscosity within specification

Annexure-2: Batch Record

Batch Number	Process Step	Time	Operator
12345	Viscosity Adjustment	09:00 AM	Jane Smith

Annexure-3: Quality Control Test Report

Test Parameter	Result	Specification	Remarks
Viscosity	2000 cP	1500-2500 cP	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