Agar Coating on Coconut Meat Surface Using Electrostatic Coating Technique

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Suthicha Chinnabutr
Sapphaya Thong-ngam
Pantaree Thepmala
Kobsak Kanjanapongkul


Electrostatic coating technique using direct current at low voltage was employed for agar coating on coconut meat surface. The study revealed that 0.5-1 %w/v agar solutions can be used as coating materials. The agar coating layer (ACL) of the electrostatic coated sample was 150 to 200% thicker than that of the samples coated using the tradition method. This could be due to the action of electrostatic attraction force so that the agar molecules were accumulated around the sample surface and therefore accelerated gel formation. The thickness of the ACL increased with the voltage concentration and coating time, while the ACL’s concentration strongly depended on the coating temperature. It was also found that the ACL on the electrostatic coated sample was more uniform while the process time was much shorter. The results suggests that electrostatic coating technique can be applied to a food coating process as it can shorten the process time and control the uniformity, thickness and density of the coating layer.


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Chinnabutr, S., Thong-ngam, S., Thepmala, P., & Kanjanapongkul, K. (2020). Agar Coating on Coconut Meat Surface Using Electrostatic Coating Technique. Journal of Food Technology, Siam University, 15(1), 53–63. Retrieved from
บทความวิจัย (Research Articles)


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