Simonič Marjana
Faculty of Chemistry and Chemical Engineering, University of Maribor, Smetanova 17, 2000 Maribor, Slovenia.
Membranes (Basel). 2022 Oct 13;12(10):993. doi: 10.3390/membranes12100993.
Acid whey is derived from fresh cheese. The proteins were isolated by a monolithic ion-exchange column. The remaining whey fraction was used as a starter culture substrate of kefir grains. The aim of this work was, firstly, to study the possibility of column replacement by a UF membrane. If we succeeded, the concentrate would be used as a starter culture substrate of kefir grains. The second part of the research was to purify the remaining solution. The idea was to separate this solution to the permeate and the concentrate by nanofiltration. Further application of both filtration streams was tested as aqueous solutions or dried matter. Chemical and microbiological analyses were performed of both the permeate and the concentrate. The permeate analyses showed that lactose had been fully removed. The aqueous permeate was not stable, mainly due to an increase of total bacteria from 10 to 10 CFU/mL. Therefore, the permeate was spray-dried. The dry permeate was added to the moisture solution in different concentrations. The results showed that up to 0.5% of the dry permeate could be added to the moisturizing solution, with negligible changes in properties having the ability to inhibit acne growth. Anaerobic digestion of industrial sludge was performed with the addition of an aqueous concentrate, which showed improvement in anaerobic fermentation.
酸性乳清源自新鲜奶酪。蛋白质通过整体式离子交换柱进行分离。剩余的乳清部分用作开菲尔粒的发酵剂培养底物。这项工作的目的，首先是研究用超滤膜替代柱子的可能性。如果成功，浓缩物将用作开菲尔粒的发酵剂培养底物。研究的第二部分是纯化剩余溶液。想法是通过纳滤将该溶液分离为渗透物和浓缩物。对两种过滤流作为水溶液或干物质的进一步应用进行了测试。对渗透物和浓缩物都进行了化学和微生物分析。渗透物分析表明乳糖已被完全去除。水性渗透物不稳定，主要是因为总细菌数从10增加到10 CFU/mL。因此，对渗透物进行了喷雾干燥。将干燥的渗透物以不同浓度添加到保湿溶液中。结果表明，高达0.5%的干燥渗透物可以添加到保湿溶液中，且对具有抑制痤疮生长能力的性质影响可忽略不计。在添加水性浓缩物的情况下对工业污泥进行厌氧消化，结果表明厌氧发酵得到了改善。
