Thermodynamic analysis of the static patterns of moisture absorption by a biopolymer based on its hygroscopic characteristics

Currently, the world community is seriously concerned about the rapid and unpredictable growth in the use of synthetic food packaging, which leads to a constant accumulation of non-biodegradable waste, the disposal of which is difficult and expensive. This determines the rationality of replacing such packaging materials with biodegradable edible films, in particular, based on pectin substances of natural origin, which are natural structure-forming agents obtained from non-recyclable waste during the processing of plant materials. In this aspect, it is interesting to use watermelon peels, a significant part of the harvest of which does not reach the consumer due to its insufficient condition or simply remains in the fields unharvested. Moreover, the watermelon rind contains up to 13,4 % of pectin substances, 8,1 % of which are protopectin, which determines the strength parameters of berry tissue. To solve the problems posed in the work, in particular, the choice of rational operating parameters and modeling of drying, a study of its statics has been carried out by determining the hygroscopic characteristics and thermodynamic regularities of moisture absorption by pectin gel from a watermelon rind, which made it possible to determine the binding energy of moisture with a dry residue and, as a consequence, in fully assess the energy consumption during the procedure of its dehydration, as well as recommend the final rational moisture content of the finished product as a result of the drying process for its long-term preservation during its use and storage and, in addition, determine the appropriate environmental parameters that need to be maintained in commercial, industrial and warehouse premises.

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