Production of concentrated whey beverage by osmotic membrane distillation: Comparative evaluation of feed effect on process efficiency and product quality

Abstract

Reconstituted whey powder (RCW), whey released after rennet-coagulation (PW) and microfiltration permeate of skim milk (IW) were used to produce concentrated beverage by osmotic membrane distillation (OMD). Effect of feed type on OMD performance and on final quality were evaluated. The use of IW not only promoted the greatest initial permeate flux but also reduced the operation time of OMD needed to reach 15.7 ± 0.4 ºBrix, as compared with PW and RCW. Based on mineral and amino acid intake, the concentrated IW corresponded to 50 ± 3% and 76 ± 5% of equal amount of skim milk, respectively. While IW beverage was a good source of isoleucine, PW beverage provided adequate intake of valine besides leucine and isoleucine. Along with the better process performance, the use of IW in OMD resulted in obtaining plain concentrated whey beverage having comparable nutritive value with the PW and the RCW, and better clarity.