The aim of this study was to characterize the properties of lactoferrin (LF) obtained in a process developed for its isolation from acid whey derived from the production of fresh curd cheese, using a unique technology of ion-exchange chromatography on CIM® monolithic columns. The freeze-dried lactoferrin samples produced on the pilot plant (capacity 1 m3) were examined for the purity, iron-binding capacity, antibacterial activity, and pH- and temperature-stability. Apo-LF inhibited several tested strains (enterobacteria, Staphylococcus, Streptococcus salivarius) except clostridia, lactic acid bacteria, and bifidobacteria. Sample of LF intentionally saturated with Fe3+ lost its antibacterial activity, indicating the involvement of mechanisms based on depriving bacteria of an iron source. All samples, regardless of the iron-saturation level, exhibited stability in pH range 4.0 to 11.0. LF with higher iron content (A-value = 41.9%) showed better thermal stability. Heat treatment up to 72 °C/3 s did not reduce antimicrobial activity against E. coli O157: H7 tox-. Higher purity (above 91%), higher iron-binding capacity and higher inhibitory activity against E. coli O157: H7 tox- compared to some similar products from the market was observed. These results demonstrate a high potential of monolithic ion-exchange chromatography for industrial processing of acid whey as a source of LF that can be used in new products with high-added value. The upscaling of the process is ongoing on a demonstration plant (10–30 m3/day capacity).

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Goat’s daily diet is usually based on grazing, hay and/or feed supplements. Feed supplements are crucial in the diet of high productive goats to achieve their genetic potential and breeders must choose balanced feeding regime to produce large quantities of milk without affecting the technological quality of milk. In the present study, we evaluated the influence of two commercially available feed supplements on goat milk coagulation properties and rheological properties of yoghurts. Goats of the Slovenian Alpine breed (61) were fed with two feed supplements during the 3-year experiment. Feed supplement 1 (FS1) had higher proportions of barley and alfalfa, while feed supplement 2 (FS2) had added premix of minerals and vitamins and had higher proportions of wheat and sunflower meal. Con¬sequently, FS1 had more crude fibres, which is the most probable reason for approximately 15 % higher firmness, consistency and cohesiveness (P<0.05) of yoghurts in FS1 group, compared to the FS2 group. Moreover, the rennet coagulation time (r) was shorter (P<0.05) in the FS1 group, compared to the FS2 group. Curd firmness 30 min after enzyme addition (a30) was also higher in FS1 group although the results were not statistically significant. Taking together, our results indicate that goats fed with FS1 produced milk with better technological properties compared to those fed with FS2, despite the fact that there were no significant differences in chemical composition of milk from each group. We showed that careful selection of feed supplement’s constituents could improve technological properties of goat milk. However, further studies are needed to evaluate the mechanisms of the observed differences.