Whey treatment by an electrodialysis technique

Whey is a by-product of cheese and butter production. This by-product conta ins important quantities of proteins and calcium, as well as other componen ts, which makes it's treatment attractive in older to prepare beverages or to sell it directly. Acid and/or salty wheys ale not good for direct human consumption, and they should be treated before use. The electrodialysis tec hnique is very suitable for that purpose. Nowadays, whey is used as foodstu ff for animals and/or it is rejected into the environment as a highly conta minant effluent, die to its high chemical and biochemical oxigen demand. In this work demineralization and deacidification of a butter whey and a "bon salut" cheese whey is studied in order to enhance its properties. The treat ment of the wheys was done with a five cell Kel'f type electrodialyzer. The whey was analized before and after treatment to determine the contents of calcium, proteins, fat acid, ashes, its conductivity and pH. The results sh ow that the electrodialysis is a very effective technique for desalting and deacidifying the whey. In some cases, low faradic efficiencies were obtain ed, and are associated with low initial concentrations of ions (salts and a cids). Finally, there was an important deacidification but no pH changes, a nd this is attributed to the buffer effect of the whey.