The cross-effects of dialyzed postincubates (with a cut-off at 1000 Da) oil the biomass and bacteriocin production of six strains of lactic acid bacteria were studied, and at predominance of stimulating responses was found, the characteristics of which suggested merely nutritional effects or the presence of precursor fragments of the bacteriocins. Additionally, cluster analysis of the detected responses provides an approach to define groups of highly compatible (potential consortia) or doubtfully compatible strains of lactic acid bacteria. Such a definition, which does not claim taxonomic value, has practical interest, however, in cases (e.g., silage production) in which it is convenient to use mixed inocula including strains able to establish positive interactions.