Forty strains of Lactobacillus brevis subsp. Lindneri, L. Brevis, L. Fructivorans, L. Fermentum and L. Cellobiosus isolated from Italian wheat sourdoughs and 5 ATCC type strains (one per species) were characterized on the basis of 7 parameters of acidification kinetics and 3 impedance test parameters. The total change and the maximum rate of conductance were statistically correlated with several parameters of acidification kinetics. The Principal Component Analysis (PCA) conducted on 6 parameters of acidification kinetics differentiated the strains and formed 5 groups according to species number. The differences between lactic acid bacteria isolated from the sourdoughs and the type strains, and several strains that behaved differently from their representative group were shown. The characterization defined by the analytical procedure, with a slight exception for L. Cellobiosus, was confirmed during the sourdough fermentation with selected starters. A comparison between the acidification activities of sourdough hetero- and homo-fermentative (previously characterized) lactic acid bacteria was given.
THE SOURDOUGH MICROFLORA. CHARACTERIZATION OF HETEROFERMENTATIVE LACTIC ACID BACTERIA BASED ON ACIDIFICATION KINETICS AND IMPEDANCE TEST
DE VINCENZI, Sergio
1995
Abstract
Forty strains of Lactobacillus brevis subsp. Lindneri, L. Brevis, L. Fructivorans, L. Fermentum and L. Cellobiosus isolated from Italian wheat sourdoughs and 5 ATCC type strains (one per species) were characterized on the basis of 7 parameters of acidification kinetics and 3 impedance test parameters. The total change and the maximum rate of conductance were statistically correlated with several parameters of acidification kinetics. The Principal Component Analysis (PCA) conducted on 6 parameters of acidification kinetics differentiated the strains and formed 5 groups according to species number. The differences between lactic acid bacteria isolated from the sourdoughs and the type strains, and several strains that behaved differently from their representative group were shown. The characterization defined by the analytical procedure, with a slight exception for L. Cellobiosus, was confirmed during the sourdough fermentation with selected starters. A comparison between the acidification activities of sourdough hetero- and homo-fermentative (previously characterized) lactic acid bacteria was given.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
