Designing structured resourceand energy-efficient drying technology of fish products’
To develop resource and energy efficient modes and technologies for the fish snacks (chips) production, we studied the convective drying processes of fish structured raw materials with high, medium, and low moisture content. Kinetic dependences were studied taking into account the influence of every determining parameter on the process features separately. The experiments were grouped in a series, in each of which the studied parameter affecting the process changed within the specified limits, and the other parameters were kept constant over time. The influence of parameters characterizing the species, size-mass composition, and regime conditions was studied. The moisture losses from the material was registered at certain intervals. The method of determining critical humidity is used, which includes the construction of the drying curves in semi-logarithmic coordinates. It is discovered that there is one critical point when structured fish products drying, due to the corresponding structure of the tissues and the water-holding capacity of the fish minced raw materials, as a capillary-porous colloidal substance. A mathematical equation is obtained for finding the critical moisture content of minced fish raw materials during dehydration. It is recommended to use semi-hot drying modes for fish raw materials of various fat content, which reduce the cost of electricity for the process compared to hot drying. A solution is proposed for additional reduction of energy consumption for the technological process when the heat pump is included in the drying scheme. The research results allowed us to develop an innovative technology for dried structured fish snacks (chips) production, which includes resource - and energy-efficient modes of processing raw materials. We have developed regulatory documentation for fish chips production. A heat pump prototype unit for convective drying has been developed. The design of equipment for complex mechanical processing of raw materials has been developed for the technological scheme.