Inhibition of Yersinia enterocolitica growth during cold storage of honey-sweetened milks fermented by the use of Lactobacillus casei Lc-01

U radu je istražen utjecaj fermentiranih probiotičkih napitaka od kravljeg, kozjeg i sojinog mlijeka s dodatkom bagremovog i kestenovog meda prema patogenoj bakteriji Yersinia enterocolitica. Za pripravu napitaka korištena je monokultura Lactobacillus casei Lc-01, a fermentirano je UHT kravlje mlijeko s 2,8 % mliječne masti, UHT kozje mlijeko s 3,2 % mliječne masti, te sojino mlijeko s 2,2 % masti. Dvije vrste meda dodavane su u mlijeko prije fermentacije u udjelima od 2 i 5 %. Fermentacija je provedena na 37 °C u trajanju od 25 sati, a nakon toga proizvodi su čuvani na 4 °C. Titracijska kiselost, pH-vrijednost i broj probiotičkih bakterija utvrđeni su nakon 25 sati fermentacije, te nakon 7, 14 i 21 dan čuvanja. Kravlje mlijeko fermentirano s Lc-1 najjače je inhibiralo rast bakterije Yersinia enterocolitica s dodatkom kestenovog meda u udjelu od 2 % 21. dan čuvanja. Kozje fermentirano mlijeko najjače je inhibiralo rast bakterije Yersinia enterocolitica s dodatkom bagremovog i kestenovog meda u udjelu od 5 % u 21. danu čuvanja. Sojino mlijeko fermentirano s Lc-01, najjače je inhibiralo Yersinia enterocolitica uz dodatak kestenovog meda u udjelu od 5 % u 21. danu cuvanja. Bagremov med je u svim proizvodima u svim fazama čuvanja slabije inhibirao rast Yersinia enterocolitica u odnosu na kestenov med.Influence of honey sweetened fermented goat’s, cow’s and soy milk on the growth of Yersinia enterocolitica was determined. Long life cow (2.8% of milk fat), goat (3.2% of milk fat) and soy (2.2% of fat) were fermented with monoculture Lactobacillus casei Lc-01. Acacia and chestnut honey were added before fermentation in contents of 2 and 5% w/w. Fermentation was conducted at 37 °C for 25 hours; well the cold storage was conducted at 4 °C for 21 days. During fermentation, as well as during cold storage physico-chemical and microbiological parameter were determined as follows: titration acidity, pH values and viable cells number of Lactobacillus casei Lc-01. The strongest inhibitory action against Yersinia enterocolitica had fermented cow milk storaged 21 days, with 2% of chestnut honey addition. Goat fermented milk and storaged 21 day, with addition of acacia and chestnut honey of 5%, also strongly inhibited Yersinia enterocolitica growth. Soy milk, fermented for 25 hours and cold storaged 21 days, inhibited the growth of Yersinia enterocolitica in case when 5% of chestnut honey was added. In all cases, without regard to the type of milk, chestnut honey expressed higher antagonistic potential against Yersinia enterocolitica than acacia honey