Document Detail

Validation of a model for growth of Lactococcus lactis and Listeria innocua in a structured gel system: effect of monopotassium phosphate.
MedLine Citation:
PMID:  18562029     Owner:  NLM     Status:  MEDLINE    
The effect of monopotassium phosphate (KH(2)PO(4)) on the chemical environment and on growth of Listeria innocua and Lactococcus lactis in coculture were investigated in a liquid and in a gelled microbiological medium at 12 degrees C and an initial pH of 6.2. As expected, addition of KH(2)PO(4) to both the liquid and gelled media resulted in an increase in buffering capacity. This effect on buffering capacity changed the profiles of lactic acid dissociation and pH evolution. At all gelatin concentrations studied, addition of KH(2)PO(4) increased the growth rate and the stationary cell concentration of L. lactis. In addition, the growth rate of L. innocua slightly increased but, in contrast, the stationary cell concentration remained unchanged. A new class of predictive models developed previously in our research team to quantify the effect of food model gel structure on microbial growth [Antwi, M., Bernaerts, K., Van Impe, J. F., Geeraerd, A. H., 2007. Modelling the combined effect of food model system and lactic acid on L. innocua and L. lactis growth in mono- and coculture. International Journal of Food Microbiology 120, 71-84] was applied. Our analysis indicate that KH(2)PO(4) influenced the parameters of the chemical and microbiological subprocesses of the model. Nonetheless, the growth model satisfactorily predicted the stationary cell concentration when (i) the undissociated lactic acid concentrations at which L. innocua and L. lactis growth cease were chosen as previously reported, and (ii) all other parameters of the chemical and microbiological subprocesses were computed for each medium. This confirms that the undissociated lactic acid concentrations at which growth ceases is a unique property of a bacterium and does not, within our case study, depend on growth medium. The study indicates that microbial growth depends on the interplay between the individual food components which affect the physicochemical properties of the food, such as the buffering capacity. Towards future research, it can be concluded that mathematical models which embody the effect of buffering capacity are needed for accurate predictions of microbial growth in food systems.
M Antwi; T E Theys; K Bernaerts; J F Van Impe; A H Geeraerd
Related Documents :
10521329 - Morphological and physiological responses to altitude in deer mice peromyscus maniculatus.
20501049 - Characterization of the properties of pediococcus parvulus for probiotic or protective ...
20021189 - Hepatocyte culture as an in vitro model for evaluating the hepatotoxicity of food-borne...
20417089 - Application of probiotics in food products--challenges and new approaches.
10532379 - Intestinal microflora and the interaction with immunocompetent cells.
13933509 - Changes in the microflora of haddock fillets and shucked soft-shelled clams after irrad...
3562289 - Dietary vitamin a and lung cancer: results of a case-control study among chemical workers.
10627079 - Compensatory hyperphagia after fasting tracks recovery of liver energy status.
19121769 - Hypovitaminosis d in chronic kidney disease patients: prevalence and treatment.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't; Validation Studies     Date:  2008-04-30
Journal Detail:
Title:  International journal of food microbiology     Volume:  125     ISSN:  0168-1605     ISO Abbreviation:  Int. J. Food Microbiol.     Publication Date:  2008 Jul 
Date Detail:
Created Date:  2008-07-25     Completed Date:  2008-11-13     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  8412849     Medline TA:  Int J Food Microbiol     Country:  Netherlands    
Other Details:
Languages:  eng     Pagination:  320-9     Citation Subset:  IM    
Department of Chemical Engineering, Katholieke Universiteit Leuven, W. de Croylaan 46, B-3001 Leuven, Belgium.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Coculture Techniques
Colony Count, Microbial
Culture Media / chemistry
Food Microbiology*
Gelatin / metabolism*
Hydrogen-Ion Concentration
Lactococcus lactis / drug effects,  growth & development*
Listeria / drug effects,  growth & development*
Models, Biological*
Phosphates / pharmacology*
Potassium Compounds / pharmacology*
Predictive Value of Tests
Reg. No./Substance:
0/Culture Media; 0/Phosphates; 0/Potassium Compounds; 16068-46-5/potassium phosphate; 9000-70-8/Gelatin

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Neuroticism influences pupillary responses during an emotional interference task.
Next Document:  Analysis of yeast and archaeal population dynamics in kimchi using denaturing gradient gel electroph...