Although the plasticizer concentration used is often lower than that of the edible coating itself, for this optimiza-tion study, the findings was the opposite. This could be due to the fact that carrageenan forms a firm brittle gel structure contributed by the extensive interaction between polymer molecules. Thus, a higher concentration of plasticizer (glycerol) was required to increase carrageenan coating flexibility and processability, which is done by positioning between polymer molecules and interfering with polymer–polymer interactions (Han and Gennadios, 2005). Similar polymer–plasticizer ratios were used for coating of straw-berry fruit by Ribeiro et al. (2007), where the coating mixture was prepared from 0.3% (w/v) carrageenan and 0.75% (w/v) glycerol.