Whey concentration using microfiltration and ultrafiltration

Abstract

Whey is a by-product from the dairy industryand it is produced during the manufacture ofcheese after separation of casein and fat duringmilk coagulation [1]. Due its composition thedisposal is one of the ma in problems in the dairyindustry. The biochemistry oxygen demand(BOD) is 32,000–60,000 ppm, which creates avery severe disposal problem [2]. Thus, themembrane application is a good alternative forwhey treatment. An appropriate membrane cansimultaneously fractionate, purify, and concen-trate whey components [2]. The initial protein content of 10–12% (drybasis) can be increased by ultrafiltration to resultin 35, 50 or 80% protein products, with a con-comitant decrease in lactose and some salts. The major application of microfiltration is apretreatment for ultrafiltration of whey for theremotion of substantial quantities of undesirablecomponents such as fat and casein micelles,which can have some detrimental effects on thefunctional properties of the WPC [2]. In Chile whey is used, principally for animalfeed, or simply is considered as wastewater.Therefore it is required some pre-treatmentbefore its disposal due the high values of BOD. The aim of this study was to determinate theoperating parameters during the microfiltration(MF) and ultrafiltration (UF) of whey, the possibil-ity of whey proteins recovery and to determinatethe decrease of BOD values after treatment withMF and UF.