Preguntas frecuentes

The heat stability comparison of Low acyl gellan gum Between Kelcogel F and CAGGEL LA

1. Introduction:

Low acyl gellan gum is widely used in water jelly and candy for heat stability purpose, it helps water jelly form to keep stable at the processing of heat sterilization, and helps candy decreasing mold time as well as not melting or sticking under the high temperature condition.

2. Materials and methods
2.1 Gellan gum samples
Low acyl gellan gum sample powder ( Kelcogel F, Material Number: 40280) provided by CP Kelco U.S., Inc. ( Atalnta, GA ), low acyl gellan gum sample powder ( CAGGEL-LA , Batch No: LA202507151 ) provided by CAG Hydrocolloids.

2.2 Sample preparation:|
Weigh accurately 6.0000 gm low acyl gellan gum and seperately disperse the different samples into 1200ml deionized distilled water in 2000ml beakers with magnetic stirrer. The dispersions were heated from room temperature to 95°C by water bath and maintain for 10 mins to get the clear solution. 20ml 2.7% calcium chloride solution was added into hot gellan solutions to help gel forming, the solutions were stirred for 2-3 minutes.

About 80ml of each solution was transferred into ten 100ml glass beaker and sealed by SARAN wrap film, then we prepared 15 samples for each gellan gum solution. After the solutions were cooled to room temperature and the gels were firmly set, the beakers were stored in 20 °C incubator for 12hrs.

2.3 Two heating processing methods

For each gellan gum from different suppliers, we have 15 original gelling samples made from 2.2, then we heating the samples by two different ways. The detailed heating methods are as follows:
2.3.1 Randomly taking 5 gelling samples out from 15 originals and heating these 5 gelling samples by water batch (95°C ) for 3 hrs, then cooled samples to room temperature and stored in 20 °C incubator for 12 hrs.
2.3.2 Randomly taking 5 gelling samples out from remained 10 originals and heating these 5 gelling samples by Autoclave. The heating temperature was 121 °C for 30 mins, then cooled the samples to room temperature and stored in 20 °C incubator for 12 hrs.

2.3 Gel Strength Testing method

Testing the gel strength for every sample with the texture analyzer (CT3 ), then we got the following results.

3. Results and discussion

Note: the DR value means the destroy effect by heating, more bigger DR value, less heat stability of Gellan gum.

From the results, we can see both gellan gum gel strength will be decreased by heating processing, the destroy effect of autoclave ( 121 °C for 30 mins ) is bigger than water bath ( 95°C for 3 hrs ), while the difference rate of Kelcogel F and CAGGEL-LA is very close. It means that CAGGEL-LA has the same or even better heat stability as Kelcogel F.

Picture 1. The gel strength changing with different heating ways.

4. Conclusion:

The Kelcogel F has the relatively higher gel strength than CAGGEL-LA, while for the heat stability testing, the two gellan gum samples have almost same DR value, which means the two samples have the same performance on heat stability for water jelly and candy application.