Relative abundances of bacterial phyla (pie charts) and an aggregation of the 21 most abundant bacterial genera (column charts) for the V1–V3 (A) and V3–V4 (B) regions of the 16S rRNA genes. Kefir product from Lithuania (LP), kefir grains from Lithuania (LG), kefir product from South Korea (KP), kefir grains from South Korea (KG), kefir product from Ireland (IP), kefir grains from Ireland (IG), kefir product from the Caucuses region (CP), kefir grains from the Caucuses region (CG), kefir product from Britain (BP), kefir grains from Britain (BG), kefir product from Fusion Tea (AP, Amazon), kefir grains from Fusion Tea (AG, Amazon).