Abstract: The objective of this study was to quantify the capacity of a ceramic microfiltration (MF) membrane with a pore size of 0.05 μm to remove whey proteins, lactose, ash, calcium and phosphorus from skim goat milk. Skim goat milk was concentrated three times by microfiltration at 50 ℃, and then the resultant fraction was diluted to the original volume followed by three-fold concentration under the same condition as for skim goat milk. The same treatment was conducted on the fraction obtained from the second microfiltration. During the whole process, the cumulative removal percentages of whey proteins, lactose, ash, calcium and phosphorus calculated from three filtrates were 96.17%, 86.42%, 73.39%, 34.9% and 55%, respectively. After the second filtration, the pure water flux of the membrane was reduced by 55.57%, and the membrane flux was restored to 99.21% of the initial level after cleaning the membrane with 2% NaOH and 1% nitric acid solution. Ceramic membrane with 0.05 μm pore size was effective for the separation of casein and other components.Therefore, this technology is suitable for processing casein micelle powder, whey protein powder, lactose and other milk-based products from fresh milk without cheese whey.

Key words: microfiltration, ceramic membrane, goat milk, separation, whey protein, casein