Fruit juices, deacidification

The present ED industry has experienced a steady growth rate of about 15% since 15 years (Srikanth, 2004). The most important industrial ED application is still the production of potable water from brackish water. However, other applications either in the semiconductor industry for the production of ultrapure, that is, completely deionized water without the chemical regenerations of IERs or in the food industry (i.e., whey demineralization, tartaric stabilization of wine, fruit juice deacidification, and molasses desalting) are gaining increasing importance with large-scale industrial installations. 

Electrodialysis is a well-proven technology with a multitude of systems operating worldwide. In Europe and Japan, electrodialysis dominates as a desalting process with total plant capacity exceeding that of reverse osmosis and distillation [3]. Electrodialysis with monopolar membranes is applied to different food systems, to demineralization of whey [5-8], organic acids [9], and sugar [10,11], separation of amino acids [12] and blood treatments [13], wine stabilization [14—16], fruit juice deacidification [17-19], and separation of proteins [20-22]. These applications use the sole property of dilution-concentration of monopolar lEMs in a stack of as many as 300 in an electrodialysis cell. 

Cheese whey demineralization Desalting of protein hydrolysates (i.e., soy sauce), sugar solutions, molasses, and polysaccharide dispersions Deacidification of fruit juices Tartaric wine stabilization Flavor recover from pickle brines... 

FIG. 17 Schematic layout of a three-compartment ED stack for the deacidification of fruit juices a, anionic membrane c, cationic membrane R , generic anion X+, generic cation. 

Vera, E., Ruales, J., Domier, M., Sandeaux, J., Sandeaux, R., and Pourcelly, G. 2003. Deacidification of clarified passion fruit juice using different configurations of electrodialysis. J. Chem. Technol. Biotechnol. 78, 918-925. 

Figure 10.17 Flow schematic of electrodialysis systems used to exchange target ions in the feed solution, (a) An all-cation exchange membrane stack to exchange sodium ions for calcium ions in water softening, (b) An all-anion exchange membrane stack to exchange hydroxyl ions for citrate ions in deacidification of fruit juice...

Based on these problematics, Vera Calle et al. [19] tested the deacidification of clarified passion fruit juice by EDBM. The stack was equipped with homopolar and BPM, forming two compartments (Figure 21.23). The reduction of acidity was... 

Adhikary SK, Harkare WP, Gowindan KP, and Nanjundaswamy AM. Deacidification of fruit juices by electrodialysis. Indian J. Technol. 1983 21 120-123. 

Chitin, chitosan, and their derivatives offer a wide range of applications including bioconversion for the production of value-added food products, preservation of foods from microbial spoilage, formation of biodegradable films, recovery of waste material from food processing discards, purification of water, and clarification and deacidification of fruit juices (Shahidi et al., 1999) (Table II). 

Food additive Clarification and deacidification of fruit juices Natural flavor extender Texture adjusting agent Emulsifying agent Food mimetic Thickening and stabilizing agent Color stabilization... 

Yet another important area of application is the clarification and deacidification of fruit juices, for example, pineapple [187] and apple [188], as well as the adsorption of polyphenols (catechins, flavans, proanthocyanidins, cinnamic acids, etc.) in white wine, responsible for browning and maderization [189]. 

Chitosan can be used for the deacidification of fruit juices Codex Alimentarius Commission (2003). Indeed chitosan salts carry a strong positive charge that can interact with proteins and hence act as... 

Deacidification of drinks Chitosan salts that carry a strong positive charge have been shown to be effective as dehazing agents. They may be nsed to control acidity in fruit juices or coffee drinks. 

Rwan, J. and Wn, J. 1996. Deacidification of grape fruit juice with chitosan. Food Science, Taiwan 23 509-519. 

The most important application of electrodialysis is the production of potable water from brackish water [82]. Avery special application is the reverse case, the production of salt. In the latter case the concentrate is the product stream whereas in the former case the diluate stream is the product. Moreover, there is an increasing number of industrial applications where ions have to be removed from.a process stream such as demineralisation of whey, deacidification of fruit juices, production of boiler feed water, removal of organic acids from a fermentation broth.lt is even possible to separate amino acids from each other as will be shown below. 

Fruit juice processing is a major use for membrane filters, particularly for clarification (using microfiltration or ultrafiltration), concentration (using reverse osmosis) and deacidification (using electrodialysis). The clarification of apple juice by ultrafiltration is now an important process, whether making clear juice or natural (i.e. cloudy) ones. 

Ultraflltration is also used to fractionate and concentrate proteins from potato processing wastewaters. Other protein wheys can be processed by reverse osmosis. Electrodialysis is used for a number of applications in the food and beverage industry, including deionization or deacidification of fruit juices, wines and, in the dairy industry, milk and whey. It often competes directly with ion exchange processes. 

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