OPTIMIZATION OF DESIGN AND OPERATING PARAMETERS FOR EXTRUDATE COOLING SYSTEM

OWATVH

Abstract

One of the main operations in the production of extrudates from wheat grain and subsequent obtaining of textured flour in food systems is its cooling. To prevent caking of the protein component of the product, it must be cooled to a temperature no more than 10 °C above the ambient temperature An analysis of technical means for cooling extrudates has shown that they have a low intensity of cooling the finished product due to deficiencies in the design of the heat exchanger. The aim of the study was to improve the technological process of producing extrudates by modifying the material cooling link and optimizing the design and operational parameters of the cooling unit, taking into account the theoretically calculated compromise optimum. To optimize the semi-finished product cooling process, methods of experiment planning and mathematical processing of the obtained data were used. The implementation of the plan was carried out using the regression analysis package DataFit and the specialized software package Statistics from the Maple computer mathematics system. Studies were conducted taking into account the influence of factor indicators on the duration and energy intensity of the extrudate cooling process. In a series of experiments, the values of the resultant indicators of the extrudate cooling process were refined within the parametric range of the compromise optimum formed by the design and operating parameters of the installation. The following quality indicators of grain extrudate were achieved: moisture content of 8.74 % (a reduction in moisture by 15–27 %), a reduction in protein loss by 13.65 %, while maintaining the remaining chemical and technological characteristics. The deviation of the actual design and operating parameter data from their analogous theoretical parameters forming the compromise optimum does not exceed 5 % in absolute value. When selecting the design and operating parameters in the vicinity of the point of compromise optimum, specifically, a shaft rotation speed of 17 rpm and a blade inclination angle of 10 degrees, the actually obtained values of duration (0.073 hours) and energy consumption (0.004 kW·h/kg) deviate from their corresponding theoretically calculated values by no more than 5 % in absolute terms.