Why Glucosamine Chondroitin Calcium Tablets Turn Yellow — and How to Fix It

Introduction

Many manufacturers of glucosamine chondroitin calcium tablets face the same frustrating issue:

Freshly compressed tablets appear white and uniform, but after a few hours—or once bottled—they begin to yellow, grey, or show color inconsistency.

Even with controlled temperature, humidity, and light, the problem persists.

The real cause is not the environment—it’s the raw materials and formulation.
This article explains the root causes and provides practical, production-ready solutions.

Root Causes of Tablet Discoloration

Tablet discoloration is primarily driven by chemical reactions within the formulation.

Key Factors

Insight: Environmental control alone cannot stop these reactions—it can only slow them.

Typical Discoloration Pattern

· Immediately after compression: white, uniform

· After 2–24 hours: slight yellowing or greying

· Final product (in bottle): visible color variation → customer complaints

5-Step Solution to Prevent Discoloration

1. Optimize Raw Materials (Highest Priority)

· Use high-purity glucosamine HCl (low reducing sugar content)

· Select refined chondroitin (low protein, low ash)

· Choose low heavy-metal calcium carbonate 

· Add approved antioxidants (e.g., vitamin C, citric acid) 

2. Adjust Formulation pH

Slightly acidic or neutral conditions help suppress browning.

· Add citric acid or malic acid 

· Neutralize alkaline effects from calcium carbonate

3. Improve Tableting Process

· Minimize residual moisture after granulation

· Reduce exposure to ambient humidity

· Increase tablet density to limit oxygen uptake

· Store tablets sealed immediately after compression 

4. Control Intermediate Handling

5. Upgrade Packaging

Packaging plays a critical role in final product stability.

· Use high-barrier bottles (e.g., EVOH multilayer) 

· Add desiccants + oxygen absorbers 

· Apply foil sealing + tight caps 

· Fill in low-humidity environments 

Quick Fix (Immediate Implementation)

If reformulation is not possible immediately:

· Seal tablets right after compression

· Reduce workshop humidity

· Add desiccants and oxygen absorbers

· Shorten storage and transfer time

Long-Term Solution: Film Coating

The most effective and widely used solution is film coating.

Benefits

· Isolates tablets from air, moisture, and metal ions 

· Prevents discoloration without changing formulation

· Improves appearance and product consistency

Conclusion: Film coating is the most reliable way to eliminate discoloration issues.

Conclusion

Tablet discoloration is not a simple environmental issue—it is a formulation-driven chemical problem.

To solve it effectively:

· Start with raw material quality

· Adjust formulation chemistry

· Control processing and packaging

· Consider film coating for long-term stability

- Contact us today for more information.