Scraped surface heat exchangers in food industry

The food industry often faces some viscous, high-viscosity, particle-containing liquids or liquid products that require a certain crystallization process, usually need to complete the heating and cooling, crystallization, pasteurization, cooking, Scraped Surface Heat Exchanger (SSHE) is an ideal solution for completing these processes due to its special structure. It is a heat exchanger that stirs the material liquid with the help of a rotating scraper and continuously scrapes the heat transfer surface to speed up the heat transfer efficiency and heat transfer uniformity. The rotating scraper continuously stirs and continuously removes the deposits on the heat transfer surface, which makes it have the characteristics of high heat transfer efficiency, high heating uniformity, and no coking film, which is favored by manufacturers in the food processing industry.

In an ice cream production plant, the appropriate ice cream mix is pumped together with air in o a scraped surface heat exchanger, through the heat transfer of the refrigerant medium (usually ammonia, freon or carbon dioxide) in the jacket of the scraped surface heat exchanger and the Strong stirring makes the material complete the process of mixing, cooling, crystallization and semi-solidification, so as to obtain ice cream products with fine and smooth, good shape and high expansion rate [1~4]. In margarine manufacturers, scraped surface heat exchangers are used in the quenching process of oils and fats. Under extremely high cooling efficiency, the fats complete the process of aeration, supercooling, and crystal nucleation, and then adjust the crystal form through the kneading process to produce Delicate and glossy margarine products with certain ductility, stability and whipping properties [5~8]. Some food manufacturers use scraper heat exchangers with a certain shear rate, high heat exchange efficiency and little damage to particles, etc., and apply them to the production of cream sandwich products with certain stability [9], starch gelatinization in candy production , emulsifier mixing, caramelization and concentration processes [10] and sterilization processes for the production of strawberry jam, pudding, etc. [11]. Some gelatin manufacturers use scraped surface heat exchangers to complete the gelatin concentration and gelation process [12]. There are also some food manufacturers that use scraper heat exchangers to complete the continuous ultra-high temperature sterilization process of highly viscous materials (yogurt, sucrose, dairy products, mashed potatoes, etc.) [13], and scraper heat exchangers are also used. To study the shear rate, pressure, temperature, residence time, heat transfer rate in the production process of butter, ice cream, ice cream, cream, puff, chocolate, starch, hazelnut paste, sucrose, cheese, cocoa butter, cocoa butter emulsion production process optimization of key production parameters.

Reference

     1       Ndoye F T, Hernandez-Parra O, Benkhelifa H, et al. Influence of operating conditions on residence time distributions in a scraped surface heat exchanger during aerated sorbet production. Journal of Food Engineering, 2018, 222:126-138.

     2       Hernandez-Parra O, Ndoye F T, Benkhelifa H, et al. Effect of process parameters on ice crystals and air bubbles size distributions of sorbets in a scraped surface heat exchanger. International Journal of Refrigeration. 2018,92: 225-234

     3       Saraceno L, Boccardi G, Celata G P, et al. Development of two heat transfer correlations for a scraped surface heat exchanger in an ice-cream machine. Applied Thermal Engineering, 2011, 31(17-18):4106-4112.

     4       Eisner M D, Wildmoser H, Windhab E J. Air cell microstructuring in a high viscous ice cream matrix. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2005, 263(1-3):390-399.

     5       Sullo A, Arellano M, Norton I T. Formulation engineering of water in cocoa – Butter emulsion. Journal of Food Engineering, 2014, 142:100-110.

     6       Rønholt S, Kirkensgaard J J K, Høyer K F, et al. The effect of capacity, rotational speed and storage on crystallization and rheological properties of puff pastry butter. Journal of the American Oil Chemists Society, 2014, 91(1):29-38.

     7       émilie Lefébure, Sébastien Ronkart, Brostaux Y, et al. Investigation of the influence of processing parameters on physicochemical properties of puff pastry margarines using surface response methodology. LWT-Food Science & Technology, 2013, 51(1):225-232.

     8       Miskandar M S, Man Y B C, Yusoff M S A, et al. Effect of scraped-surface tube cooler temperatures on the physical properties of palm oil margarine. Journal of the American Oil Chemists' Society, 2002, 79(9):931-936.

     9       S. Rønholt, Kirkensgaard J J K, K. F. Høyer, et al. The Effect of Capacity, Rotational Speed and Storage on Crystallization and Rheological Properties of Puff Pastry Butter. Journal of the American Oil Chemists' Society, 2014, 91(1):29-38.

  10       Luca D’Addio, Carotenuto C, Natale F D, et al. A new arrangement of blades in scraped surface heat exchangers for food pastes. Journal of Food Engineering, 2012, 108(1):143-149.

  11       Wang Y Y, Russell A B, Stanley R A. Mechanical damage to food particles during processing in a scraped surface heat exchanger. Food and Bioproducts Processing, 2002, 80(1):3-11.

  12       Regand A, Goff H D. Effect of Biopolymers on Structure and Ice Recrystallization in Dynamically Frozen Ice Cream Model Systems. Journal of Dairy Science, 2002, 85(11):2722-2732.

  13       Depypere F, Verbeken D, Torres J D, et al. Rheological properties of dairy desserts prepared in an indirect UHT pilot plant. Journal of Food Engineering, 2009, 91(1):140-145.