Abstract:

The carboxymethyl konjac glucomannan (CMK) made from konjac glucomannan (KGM) from Amorphophallus
bulbifer was used as the film-forming material to formulate a thermosensitive edible film. The influence of CMK concentration,
CMK-to-KGM ratio, sodium alginate (as reinforcer) concentration, glycerol (as plasticizer) concentration, drying temperature
and time on tensile strength (TS), elongation at break (E), water vapor permeability (WVP) of edible films was investigated.
These film-forming components were optimized by four-variable quadratic general rotary combination design and validated by
experiments. The optimum film-forming conditions were found to be 1.60%－1.62% CMK, 0.08%－0.09% KGM, 0.31%－
0.33% sodium alginate, and drying at 70 ℃ for 5.0 h. The TS of the resulting edible film showed a 95% possibility at pressures
above 53.78 MPa. Moreover, the mathematical model developed in this study had good prediction ability.

Key words: Amorphophallus bulbifer, konjac glucomannan (KGM), thermosensitive edible film, formulation optimization