Manufacture of fermented lactic beverages containing probiotic cultures

Lactic beverages (LB) are products prepared with yogurt, whey, and other ingredients; they are popular among consumers in Brazil. LB containing probiotics were manufactured to study bacteria viability and to evaluate product characteristics during shelf life. Although counts decreased, 5.3 x 10(6) CFU/mL of probiotics in average after 28 d were found. LB behaved as pseudoplastic fluids with thixotropy, and flow curves were best fitted by Oswald-de-Waele model. Apparent viscosity and pH decreased slightly with storage. LB showed phase separation increasing until 35% after 14 d, stabilizing after. Finally, microscopy observations showed a dispersion of protein particles. Filamentous and spherical structures corresponded to guar and starch that were added as stabilizers. No differences were noticed between products containing yogurt bacteria and those with probiotics.