🌟 Case Study : Premium Hot-Fill Mango Juice Stabilization with Low-Acyl Gellan Gum
🥭 Introduction
In today's beverage market, consumer appeal hinges on visual clarity, product stability, and clean-label simplicity. A regional co-packer launching a new hot-fill mango juice line encountered three major hurdles:
- Pulp Sedimentation during hot-fill (85 °C) and subsequent storage
- Haze Formation that undermined product brilliance
- Ingredient Complexity from multi-gum blends, conflicting with clean-label goals
After unsuccessful trials with pectin, xanthan, and mixed stabilizer systems, the team turned to low-acyl gellan gum, renowned for its irreversible, heat-stable gel network and ultra-clear appearance, to deliver the desired suspension and clarity—using only one hydrocolloid on the label.
🎯 Project Objectives
| Objective | Target |
|---|---|
| Heat-Stable Suspension | Zero visible pulp sediment after 14 days at 30 °C |
| Crystal Clarity | ≥ 90 % light transmittance at 600 nm |
| Clean-Label Declaration | Ingredient list: “mango, water, sugar, gellan gum (E 418)” only |
| Operational Compatibility | No modifications to existing pasteurizer (85 °C, 10 min) or hot-fill line |
🧪 Technical Challenges
- Rapid Sedimentation: Mango puree solids (~20 % w/w) formed a distinct layer within hours at ambient temperature.
- Thermal Breakdown: Conventional gums lost viscosity at high temperatures, leading to haze and phase separation.
- Label Constraints: Desire to avoid multiple gums (e.g., "pectin, xanthan gum") in favor of one recognizable ingredient.
💡 Solution Overview: Low-Acyl Gellan Gum
Low-acyl gellan gum sets into a firm, three-dimensional network on cooling that remains intact and heat-stable during and after hot-fill pasteurization. Its fine mesh structure suspends the smallest pulp particles without imparting haze.
🔬 Detailed Formulation & Processing Protocol
1. Ingredient Selection & Dosage
- Hydrocolloid: Low-acyl gellan gum (food-grade, E 418)
- Usage Rate: 0.035 % w/w (0.35 g per liter of finished juice)
2. Pre-Hydration & Dispersion
- Heat 10 % of the total process water to 80 °C in a small holding vessel.
- Gradually sprinkle the calculated amount of gellan gum under gentle stirring (300 rpm) for 5 minutes, ensuring complete dispersion and avoiding lump formation.
3. Main Mixing & Homogenization
1).Juice Base Integration- Transfer the pre-hydrated gellan slurry into the main mixing tank.
- Add mango puree (20 % solids) and sugar syrup.
- Maintain 80 °C and stir at 300 rpm for 7 minutes to achieve a uniform blend.
4. Hot-Fill Pasteurization
1).Heat-Hold- Ramp temperature to 85 °C, hold for 10 minutes (standard pasteurization).
- Use inline temperature probes to maintain accuracy within ± 0.5 °C.
5. Filling & Gel Setting
1).Bottle Filling- Fill pre-sterilized bottles at 80–85 °C to prevent premature gelation in lines.
- Convey through a cooling tunnel to ambient in 10 minutes.
- Allow bottled juice to set at 25 °C for 4 hours before labeling.
📊 Measurable Results
| Metric | Before (Pectin + Xanthan) | After (Gellan 0.035 %) |
|---|---|---|
| Pulp Sedimentation (14 days @ 30 °C) | 15 mm layer | ≤ 1 mm |
| Light Transmittance (600 nm) | 75 % | 92 % |
| Haze Formation | Noticeable | None |
| Ingredient List | 4 items (complex) | 4 items (simplified) |
| Cost Impact per L | + € 0.04 | + € 0.05 |
- 🔒 Suspension Stability: Virtually no sediment formed, even after two weeks at room temperature.
- 💎 Crystal Clear Appearance: Premium shelf presence with brilliant transparency.
- 🏷️ Clean-Label Success: "Mango, water, sugar, gellan gum (E 418)" resonated strongly in consumer tests.
- ⚙️ Process Efficiency: Implemented without any changes to existing pasteurization or filling equipment.
🗣️ "Low-acyl gellan gum completely eliminated sedimentation in our hot-fill mango juice-delivering unrivaled clarity and stability."
🔍 Key Insights & Best Practices
- Pre-Hydration Accuracy: Hydrate gellan in a small water fraction at 80 °C to avoid lumps.
- Precise Heat-Hold: Maintain 85 °C for full network activation.
- Gentle Shear Mixing: Preserve clarity by minimizing air entrainment.
- Sufficient Rest Time: Allow at least 4 hours at room temperature for complete gel bond formation.
🏁 Conclusion
By leveraging low-acyl gellan gum and a tailored processing protocol, the co-packer achieved:
- Exceptional Suspension: No visible pulp settling
- Premium Clarity: ≥ 92 % light transmittance
- Clean-Label Appeal: Simplified ingredient list
- Operational Simplicity: No equipment modifications required
This case study underscores how low-acyl gellan gum delivers heat-stable, ultra-clear, and consumer-friendly hot-fill beverages, setting a new benchmark for premium juice products.
