Influence of the probiotic starter cultures Lactobacillus acidophilus M92 and Enterococcus faecium L3 on cabbage juice fermentation

U ovom je radu ispitana primjena odabranih bakterijskih kultura Lactobacillus acidophilus M92, Enterococcus faecium L3 i Leuconostoc mesenteroides LMG 7954 za proizvodnju fermentiranog probiotičkog napitka od soka kupusa. Autohtono prisutne bakterije mliječne kiseline nisu bile dostatne za spontanu fermentaciju soka kupusa, jer je koncentracija proizvedene mliječne kiseline bila niska tijekom 72 sata fermentacije, a pH vrijednost je iznosila od 5,95-6,21. Zbog toga je provedena kontrolirana fermentacija soka kupusa s probiotičkim sojevima Lactobacillus acidophilus M92 i Enterococcus faecium L3, te starter kulturom Leuconostoc mesenteroides LMG 7954. Tijekom kontrolirane fermentacije soka kupusa, probiotički sojevi proizveli su cca 10 g/l mliječne kiseline, pH vrijednost je iznosila oko 4,0, a broj živih stanica je ostao visok (~10 stanica/ml). Visok broj živih stanica probiotičkih sojeva Lactobacillus acidophilus M92 i Enterococcus faecium L3 održao se tijekom 4 tjedna čuvanja pri temperaturi od 4 C. Primijenjene starter kulture preživjele su proces liofilizacije u visokom broju (cca 108 stanica/ml), a kao najotporniji pokazao se soj Leuconostoc mesenteroides LMG 7954. Broj živih stanica liofiliziranih bakterijskih kultura ostao je nepromijenjen tijekom tri mjeseca čuvanja. Nadalje, bakterijske kulture, izolirane tijekom spontane fermentacije soka kupusa, ispitane su kao autohtoni sojevi bakterija mliječne kiseline za primjenu u proizvodnji fermentiranog soka kupusa. SDS-PAGE elektroforeza 13 bakterijskih izolata pokazala je da se radi o 7 različitih sojeva bakterija. Svi bakterijski izolati, kao i primjenjene starter kulture, pokazali su antibakterijsko djelovanje prema šest različitih test mikroorganizama što je jedno od važnih svojstava potencijalnih starter kultura.Research was undertaken to determine the suitability of cabbage juice as a raw material for production of probiotic fermented beverage by lactic acid bacteria (Lactobacillus acidophilus M92, Enterococcus faecium L3 and Leuconostoc mesenteroides LMG 7954). Autochthonous lactic acid bacteria were not suitable for spontaneous cabbage juice fermentation, because the concentration of produced lactic acid was low during the 72 hours of fermentation, and pH was from 5,95 to 6,21. Because of that, probiotic strains Lactobacillus acidophilus M92 and Enterococcus faecium L3, as well as starter culture Leuconostoc mesenteroides LMG 7954 were introduced in cabbage juice fermentation. During this controlled fermentation, probiotic strains have produced cca 10 g/l lactic acid, pH was around 4,0, and number of live cells stayed high (~10 cells/ml). Number of viable count of probiotic bacteria Lactobacillus acidophilus M92 and Enterococcus faecium L3 maintaned high during 4 weeks of the preservation at 4 C. Choosen starter cultures survived successfuly the freeze-drying process (~10 cells/ml) and the most resistant was Leuconostoc mesenteroides LMG 7954. The number of live cells stayed immutable during the three months of preservation. Furthermore, characterisation of lactic acid bacteria isolated from spontaneous cabbage juice fermentation was additionally carred out as a possible starter cultures consisting of autochtonous lactic acid bacteria for the production of fermented cabbage juice. Phenotypic characterization of 13 isolated strains was done by SDS-PAGE of whole cell proteins. Electrophoretic pattern revealed 7 different bacterial strains. All of this strains and the choosen starter cultures have showed antibacterial activity against 6 different test microorganisms which is one of the desirable properties of potential starter cultures