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Three basic samples of beers were produced: A, B and C. The grit of A and B contained as unmalted adjuncts 15% (plus 10% of saccharose) and 25% of sorghum grains or maize grits, respectively. The reference beer C was produced with barley malt only. The study of the effects of the unmalted adjuncts on the brewing and the quality of beer revealed that: (a) the use of 15 to 20% of maize or 25% of sorghum increased the content of iso-compounds in wort; (b) the combination of maize grit and saccharose improved the colour of the wort and beer; (c) the addition of 25% sorghum extended saccharification time, slowed down both wort and beer filtration and also produced wort of a darker colour and beer with a slightly bitter aftertaste.

-Twenty-seven propionic acid bacteria (PAB) strains were studied for their ability to produce metabolites, which stimulated the growth of six Bifidobacterium strains. In addition, the 27 investigated PAB strains were examined for their influence on the growth of four Gram(-) strains belonging to species Escherichia coli and Yersinia enterocolitica, their abilities to survive at pH 2.0, 2.5, 3.0 and in the presence of 4% bile salts as well as their sensitivity against 12 selected antibiotics. All PAB strains stimulated growth of from 3 to 6 of the examined Bifidobacterium strains and simultaneously produced antibacterial metabolites against Gram(-) rods. Fifteen PAB strains inhibited growth of the particular Bifidobacterium strains. Five PAB strains were resistant to acidity surviving for 2 h in pH 2.5 at population level 10 2 -10 6 cfu . mL -1 and 3 strains were resistant to bile salts. Only one PAB strain survived in both the acidic and the bile salt environments. All PAB strains were sensitive to a majority of the antibiotics used in the investigations. Bifidobacterium / Propionibacterium / Gram(-) rod / stimulation / inhibitionRésumé -Stimulation de la croissance de Bifidobacterium par les bactéries propioniques. Vingt sept souches de bactéries propioniques (PAB) ont été examinées pour leur aptitude à produire des métabolites stimulant la croissance de six souches de Bifidobacterium. Par ailleurs, ces 27 souches de PAB ont été examinées pour leur influence sur le développement de quatre souches Gram(-) des espèces Escherichia coli et Yersinia enterocolitica, pour leur capacité de survie dans un environnement à pH 2.0, 2.5, 3.0 et en présence de 4 % de sels biliaires ainsi que pour leur sensibilité à douze antibiotiques sélectionnés. Toutes les souches de PAB ont stimulé le développement de 3 à 6 des souches examinées de Bifidobacterium en produisant en même temps des métabolites antibactériens contre les bacilles Gram(-). Quinze souches de PAB ont eu un effet inhibiteur sur le développement des souches individuelles de Bifidobacterium. Cinq souches de PAB ont résisté à l'acidité et ont 113