Respiratory Physiology of Lactococcus lactis in Chemostat Cultures and Its Effect on Cellular Robustness in Frozen and Freeze-Dried Starter Cultures.

In this study, we used chemostat cultures to analyze the quantitative effects of the specific growth rate and respiration on the metabolism in CHCC2862 and on the downstream robustness of cells after freezing or freeze-drying. Under anaerobic conditions, metabolism remained homofermentative, although biomass yields varied with the dilution rate (). In contrast, metabolism shifted with the dilution rate under respiration-permissive conditions.

Presence of galactose in precultures induces lacS and leads to short lag phase in lactose-grown Lactococcus lactis cultures.

Lactose conversion by lactic acid bacteria is of high industrial relevance and consistent starter culture quality is of outmost importance. We observed that Lactococcus lactis using the high-affinity lactose-phosphotransferase system excreted galactose towards the end of the lactose consumption phase. The excreted galactose was re-consumed after lactose depletion.

Development of the ETOC: a European test of olfactory capabilities.

A number of smell tests designed to evaluate human olfactory capabilities have been published, but none have been validated cross-culturally. The aim of this study was therefore to develop a reliable and quick olfactory test that could be used to evaluate efficiently the olfactory abilities of a European population. This test, named ETOC and based on a combination of a supra-threshold detection task and an identification task, was designed to be a cross-cultural tool that would measure the decline in olfactory performance with ageing.