DIRECT MEASUREMENT OF PH PROFILES IN GEL BEADS IMMOBILIZING LACTOBACILLUS-HELVETICUS USING A PH SENSITIVE MICROELECTRODE

Authors
MASSON F LACROIX C PAQUIN C
Citation
F. Masson et al., DIRECT MEASUREMENT OF PH PROFILES IN GEL BEADS IMMOBILIZING LACTOBACILLUS-HELVETICUS USING A PH SENSITIVE MICROELECTRODE, Biotechnology techniques, 8(8), 1994, pp. 551-556
Citations number
24
Categorie Soggetti
Biothechnology & Applied Migrobiology
Journal title
Biotechnology techniques → ACNP
ISSN journal
0951208X
Volume
8
Issue
8
Year of publication
1994
Pages
551 - 556
Database
ISI
SICI code
0951-208X(1994)8:8<551:DMOPPI>2.0.ZU;2-3
Abstract
A H+-selective liquid membrane microelectrode was prepared and used to measure the pH profile evolution during colonization of gel beads imm obilizing Lactobacillus helveticus in a whey permeate medium. A large pH gradient was observed in a highly active periferal layer thickness that decreased from 500 to 300 mum for an immobilized cell population that increased from 5.8 x 10(9) to 3.1 x 10(10) CFU/g. The flat pH pro file (pH 4.4) in the central part of the bead was attributed to a high concentration of the inhibitory undissociated form of lactic acid.