Exopolysaccharide production by Propionibacterium acidi-propionici on milk microfiltrate.
OBJECTIVE
The aims of this work were to evaluate growth and exopolysaccharide (EPS) production properties of Propionibacterium acidi-propionici DSM 4900 on milk permeate.


RESULTS
Anaerobic growth on milk permeate was only possible if supplemented with yeast extract (YE). Fermentation capacities of the strain were significantly improved by further increasing the supplemented YE. At 5 g l(-1) YE, consumption of 45 g l(-1) lactose to produce 9 g l(-1) biomass, 34 g l(-1) organic acids and 0.65 g l(-1) EPS was observed. From a kinetic point of view, EPS production occurred during the bacteria growth phase. At the excreted polysaccharide level, the medium showed shear-thinning behaviour with a relatively high apparent viscosity of up to 30 mPa.s (milli.Pascal.second) at a shear rate of 17 s(-1).


CONCLUSIONS
EPS production by P. acidi-propionici DSM 4900 on milk permeate showed promising rheological behaviour of the milk-derived medium obtained, even at a low production level.


CONCLUSIONS
A kinetic study on EPS production by a food-grade bacterium that could be used in situ in alimentation was carried out.
Gorret
N
N
Laboratoire de Recherches de Technologie Laitière, Rennes, France. ngorret@mit.edu
Maubois
J L
JL
Ghoul
M
M
Engasser
J M
JM
D000693:Anaerobiosis; D000818:Animals; D003470:Culture Media; D005285:Fermentation; D007700:Kinetics; D008892:Milk / Q000378:metabolism*; D011134:Polysaccharides / Q000737:chemistry / Q000378:metabolism*; D011424:Propionibacterium / Q000254:growth & development / Q000378:metabolism*; D015203:Reproducibility of Results; D012212:Rheology; D015003:Yeasts
D003470:Culture Media; D011134:Polysaccharides