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Vol. 20 (2017 year), No. 3, DOI: 10.21443/1560-9278-2017-20-3
Golubeva O. A. , Grekova O. M.
The crisis of heat transfer of the first kind with milk evaporation: the problem and solutions
The problem of research and elimination of the crisis of heat exchange of the first kind for multicomponent heterogeneous food mixtures by the example of milk has been considered. The aim of this work is to create rational regimes of evaporating milk without the possibility of the crisis of heat exchange of the first kind. The experiments have been planned according to the method of combinational squares. The missing thermophysical characteristics (TPC) of the food mixture studied have been determined by the dynamic C-calorimeter method. The study of this type of the heat exchange crisis has been carried out in two stages using the modeling of evaporation process with observance of geometric, hydraulic and thermal similarity. Statistical processing of the results of experiments for determining the thermophysical characteristics of milk using the nonlinear regression method has been carried out using DataFit v 9.1.32; the results of determining the first critical heat flux density have been processed in two stages: in the first stage – using StatGraphics Plus 5.0.1, the second – DataFit v 9.1.32. The result of the work performed has been presented in the form of the mathematical models of basic milk TPCs and the empirical coefficient A for the equation of the first critical heat flux density of multicomponent heterogeneous food mixtures; as well as the range of heating density of the steam generating pipe, which causes the crisis of heat exchange of the first kind, recommendations for its elimination and maintenance of rational industrial regimes of milk evaporation. The adequacy of the mathematical models obtained has been determined by Fisher's criterion and the coefficient of determination. The limits of the application of the dependence on the determination of the first critical density of the heat flux for inhomogeneous multicomponent mixtures under conditions of natural convection at atmospheric pressure have been extended, it allows to take the next step towards creating a universal equation for its determination and forecasting the occurrence of a crisis.
(in English, стр.7, fig. 7, tables. 3, ref 6, Adobe PDF, Adobe PDF 0 Kb)
Vol. 20 (2017 year), No. 3, DOI: 10.21443/1560-9278-2017-20-3
Titova S. A., Kuranova L. K., Golubeva O. A.
Development of forage cryo minced fish technology
The technology of grinding the frozen fish raw material using the useful model of a piston-type extrusion plant with cold working bodies for fodder minced fish (cryo minced fish feed) by the method of cryoextrusion has been developed. The possibility of replacing the standard manufacturing operations (defrosting and subsequent grinding of raw materials) to the one (cryoextrusion) has been substantiated. The optimal shape of holes of the die for forcing the raw material has been determined in the form of "hourglass", the hole diameter is 7 mm, the length of the process of pushing is 40 s. It has been established that the finished product (cryo minced fish feed) has a homogeneous grinding, juicy, crumbly texture, the temperature in the thickness of the product is equal to the temperature of the raw material before processing (–18 °C). The technological scheme of producing the minced fish feed by the method of cryoextrusion has been developed. Researching the chemical composition of fish and feed of mince produced by the traditional and developed methods it has been established that protein content in the cryo minced fish feed remains unchanged. The amino acid composition of cryo minced fish feed has been determined, the amount of essential amino acids is 365.6 mg/g of protein. In the proteins of the cryo minced fish feed methionine has been contained in the minimum quantity (10.0 mg/g protein) and in the maximum – serine (155.3 mg/g protein). In the protein of the cryo minced fish feed the only limiting amino acid is methionine. The coefficient of rationality of the cryo minced fish feed whiting is equal to 0.33. The product is not toxic, is not subject to contamination with dangerous microorganisms, has high biological value, contains necessary in animal nutrition mineral elements, the energy value per 100 g of the product is 87 kcal. The combination of the processes of cryoextrusion and lyophilization allows to obtain a new food product with high organoleptic properties. The draft technical specifications for production of the cryo minced fish feed and the technological instructions for production of minced fish for feed purposes have been developed.
(in English, стр.8, fig. 3, tables. 4, ref 9, Adobe PDF, Adobe PDF 0 Kb)
Vol. 21 (2018 year), No. 3, DOI: 10.21443/1560-9278-2018-21-3
Astramovich V. L., Golubeva O. A.
Improving the process of heat treatment of the stingray stellate
The results of developing a method for combined blanching (water – steam) of a stingray stellate have been presented. The proposed method completely excludes the process of preliminary wetting and, as a consequence the hydration of stingray meat; allows one to get a semi-finished product suitable for further processing for culinary purposes, as well as for canning. Analysis of the mass-size characteristics of wings of stingray stellate, caught in the Barents Sea, made it possible to identify a group of raw materials with a specific surface area 0.2560 ± 0.05 m2/kg, which corresponds to 75 % of the block weighing 10 kg with an average mass of the sample equal to 161.33 g. The presented experimental setup allows investigating the process of blanching with water, steam or a combined method of raw materials of both plant and animal origin. To plan the experiment, the combinatorial squares method has been applied. The effectiveness of urea removal from the stingray stellate meat has been confirmed experimentally by comparing the mass fraction of carbamide in muscle scate tissue before and after preliminary heat treatment accounting the characteristics of the product under study. The developed mode of combined blanching (water – steam) for stingray is characterized by an effective removal of urea (42.5 %) and can be used for industrial blanchers of processing lines. The mathematical model of the duration of steam treatment depending on the water temperature and the duration of water treatment, makes it possible to predict the regime of preliminary heat treatment of raw materials.
(in Russian, стр.6, fig. 4, tables. 2, ref 12, adobe PDF, adobe PDF 0 Kb)
Vol. 21 (2018 year), No. 3, DOI: 10.21443/1560-9278-2018-21-3
Golubeva O. A., Titova S. A., Grekov E. O.
Cryoextrusion in technology of fish feed production
The process of grinding the frozen fish raw materials using the useful model of a piston-type extruder with cooled working bodies has been investigated. A new feed product – cryo minced fish feed – has been obtained. The possibility of replacing the standard manufacturing operations of the defrosting and subsequent grinding of raw materials by one operation of cryoextrusion has been justified. Planning of the experimental part has been performed by the method of combination squares. During the experiment, the volume of samples, their specific surface area, mass, initial and final temperatures of the working chamber, the temperature of raw materials, the temperature of the resulting minced meat, the pressure force, the time of the experiment, the mass of waste have been determined. The rational shape and size of the die holes for the extrusion of raw materials have been determined. It has been found that when using a nozzle with the "hourglass" shape of holes with a diameter of 4.5 mm and 7 mm, the duration of the extrusion process for the studied fish species is 47 to 130 s. The finished product – cryo minced fish feed – has a fairly homogeneous structure and juicy texture, the temperature in the thickness of the product is equal to the temperature of the raw material before its processing (–18 °C). The granulometric composition of the cryo minced fish feed using the sieve analysis has been determined. The statistical processing of the results of experiments to determine the pressure of frozen fish raw material by the method of nonlinear regression has been carried out using the program DataFit version 9.1.32. The regression equation describing the influence of the complex parameter – the coefficient of the hole shape, taking into account the diameter and shape of the matrix hole, and the degree of grinding of raw materials on the force of extrusion has been obtained. The expediency of using the matrix "hourglass" which allows to obtain the lowest pressure force for bony fish of the North Sea basin has been proved.
(in Russian, стр.6, fig. 3, tables. 1, ref 8, adobe PDF, adobe PDF 0 Kb)
Vol. 22 (2019 year), No. 3, DOI: 10.21443/1560-9278-2019-22-3
Golubeva O. A., Grekov E. O., Titova S. A.
Extrusion in the production technologies of North Basin cartilage fish
Nowadays one of the main tasks of developing domestic fishery complex is increasing efficiency of aquatic biological resources (ABR) extraction and optimizing their processing. The increased pace of processing of ABR is associated with the searching and introduction of energy-saving, low-waste and non-waste technologies in order to increase the quantity and expand the variety of types of both feed and food products. Stellate stingray is a valuable raw material containing a significant amount of high-quality protein, as well as a number of important trace elements for nutrition. There is a high concentration of chondroitin sulfate in the stingray meat that makes it an indispensable component in functional nutrition, as well as in the creation of special feeds. As a result of the study, rational modes of grinding Stellate stingray meat with extrusion have been recommended for using. The feasibility of using different matrices for different conditions of raw materials has been substantiated. Regression equations has been obtained for describing the effect of a complex parameter – the coefficient of the geometric shape of the hole taking into account both the diameter and the shape of the matrix hole, and the degree of grinding of raw materials on the grinding pressure. The grinding matrix with 8/7/8 "cone – cone" type openings is recommended for use in the production of feed stuffing from thawed stingray, as it allows to get grinding pressure close to the minimum and 31.33 ± 0.94 kgf/cm2 (3.07 ± 0.09 MPa) with a grinding degree of 3.09. For a blanched slope, it has been recommended to use a matrix with holes like 5.5/4.5/5.5 "cone – cone" which allows to obtain minced meat with the highest content of cartilage 14.38 ± 0.52 g per 100 g of blanched raw the pressure of 7.63 ± 0.27 kgf /cm2 (0.75 ± 0.02 MPa) and a grinding degree of 11.41. Therefor using the extrusion in the processing of North Basin fish raw materials allows to get both feed and food semi-finished products suitable for consumption and further processing.
(in Russian, стр.7, fig. 4, tables. 3, ref 11, AdobePDF, AdobePDF 0 Kb)