This study investigated the effect of temperature and residual pressure on the efficiency of vacuum drying of hydrolysates obtained from secondary raw materials from squid processing. During the experimental work, the maximum permissible process parameters of the drying process—temperature and degree of vacuum in the working chamber—were determined. The studies were conducted on samples of a solution of hydrolyzed proteins from squid skin and, partially, viscera. The source material was concentrated by ultrafiltration to a dry matter content of 30% in the samples. The drying temperature was varied at two levels: 60 and 70 °C. During the experiments, kinetic parameters were recorded to evaluate the dehydration dynamics. Curves were obtained reflecting the change in the relative mass of the samples over time, as well as temperature indicators in the working chamber and inside the product. Analysis of the experimental data showed that the specified temperature parameters in the drying chamber were reached after 80 minutes for the 60 °C mode and after 90 minutes for the 70 °C mode. Heating the inner layers of the product to the appropriate temperatures required more time: 90 and 100 minutes, respectively. The highest intensity of moisture removal was recorded at a temperature of 70°C. In this mode, the final moisture content of the samples reached 5.1%, and the total process duration was 160±5 minutes. It was noted that an increase in the drying time led to the formation of a burnt surface layer, which hindered the removal of moisture from the internal zones of the material. According to the results of the organoleptic evaluation, the sample dried at a temperature of 60°C received the highest score (17.2 points). It was found that an increase in temperature negatively affected the organoleptic properties of the hydrolysates. The minimum specific energy consumption was recorded at a residual pressure of 10±0.5 kPa. An increase in chamber pressure was accompanied by a decrease in the dehydration rate. Based on the data obtained, it is recommended to dry the solution of hydrolyzed squid proteins at a temperature of 60 °C and a residual pressure of 10 ± 0.5 kPa, which ensures a balanced combination of the quality of the finished product, processing time and energy costs.

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