The four single-strains as well as the EPS synthesised were
visualised using confocal laser scanning microscopy in combination
with Alexa Fluor® wheat germ agglutinin 488 (WGA 488)
. A water objective of
was used. The cells of LAB were investigated in
transmission mode , whereas EPS
were visualised following excitation at 488 nm and the emission
was taken between 505 and 540 nm. Prior to preparing the microscope
slides for image visualisation, each frozen strain in the
original sealed package was thawed using running tap water