Commercial supercritical fluid food processing plants

Selection of Components for Commercial Supercritical Fluid Food Processing Plants... 

Criteria for selection of equipment and components for commercial supercritical fluid processing plants for the food processing industry are listed and discussed. Unique features and designs for SCF food processing are specified. Requirements for vessels, heat exchangers, instrumentation, piping, fluid transport devices and typical ancillary equipment are reviewed. 

Passey CA. Commercial feasibility of a supercritical extraction plant for making reduced-calorie peanuts. In Rizvi SSH, ed. Supercritical Fluid Processing of Food and Biomaterials. London Blackie Academic, 1994 223-243. 

Not every pharmaceutical will eventually be comminuted by supercritical fluid nucleation, not every polymer processed for molecular weight control by supercritical fluid extraction, not every flavor concentrated by supercritical fluid extraction but some will be. Two applications listed in the table are already in commercial production, and several are in advanced pilot plant development and test market evaltiation. Hops extraction is being carried out by Pfizer, Inc. in its plant in Sydney, NE (33), and General Foods Corporation has constructed a coffee decaffeination... 

Commercialization of a supercritical carbon dioxide processed food product requires the successful application of five sequential steps 1) application of high pressure CO2 phase equilibria and fluid dynamics theory 2) knowledge of the botanicals structure and chemistry 3) performance of the "process design protocol" 4) preliminary process design and economic evaluation and 5) design, construction and start-up of the commercial-scale plant. Many decisions made during the early steps have large impacts on commercial plant performance capabilities and economic efficiency. The impact on commercial plant performance and economics should be factored into decisions made at every commercialization step. 

In the food industry, commercial plants with supercritical fluids have so far only been used with supercritical CO2 as solvent. The first plant was opened in 1981 in Bremen (Germany) for decaffeination of coffee, by a process invented in the 1970s by Zosel (1973). Plants for the production of hop extract and for the decaffeination of tea are today also in operation, for example, in Germany, England, and Australia (Voeste et al., 1997). Supercritical hydrocarbons such as propane are also used, for example, for deasphalting of heavy oils or for the removal of triglycerides from fish oils. 

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