Many lactic acid bacteria synthesize extracellular polysaccharides (exopolysaccharides, EPSs) with a large
variation in structure and potential functional properties. Although EPS production can produce detrimental
effects in alcoholic beverages, these polymers play an important role in the rheological behavior and texture of
fermented products. In this work, EPS production by two Lactobacillus suebicus strains, which were isolated
fromropy ciders,was examined in a semidefined medium. The existence of priming glycosyltransferase encoding
genes was detected by PCR. In addition, the preliminary characterization of the polymers was undertaken.
Molecular masses were determined by size exclusion chromatography revealing the presence of two peaks,
corresponding to polymers of high- and low-molecular-weight in all fractions. The composition of the EPS
fractions was analyzed by gas chromatography–mass spectrometry after acid hydrolysis, revealing that
they contained glucose, galactose, N-acetylglucosamine and phosphate, although in different ratios, suggesting
that a mixture of polysaccharides is being synthesized. We also examined the influence of the sugar source
(glucose, ribose, xylose, or arabinose) and pH conditions on growth and EPS production.