Microcalorimetric Study of Extruded Dog Food Containing Probiotic Micro-Organisms

Extruded dry dog food products claimed to have a probiotic ingredient of Enterococcus faecium (NCIMB10415) in the commercial available formulations under the brand name of ProBiotic LIVE (Bacterfield S.A., Luxembourg) were studied in the present work using a multichannel thermal activity monitor TAM III. Maximum specific growth rate, heat produced during different growth phases, and lag-phase duration were determined. The length of the lag-phase that can be used to determine the time necessary for the probiotic ingredient to restore its activity after consumption of probiotic containing extruded products was also measured. The calorimetric data confirmed the ability of the Enterococcus faecium to grow at the acidic pH conditions, modeling conditions of gastro-intestinal tract of dogs, and preserve its metabolic activity (viability) at the same level as at the neutral pH. The results obtained indicated that microcalorimetry was a precise and convenient tool for monitoring probiotic activity in complicated solid-state matrices.

[1]  R. Vilu,et al.  The effect of milk heat treatment on the growth characteristics of lactic acid bacteria. , 2011 .

[2]  J. V. Van Impe,et al.  Modelling the combined effects of structured food model system and lactic acid on Listeria innocua and Lactococcus lactis growth in mono- and coculture. , 2007, International journal of food microbiology.

[3]  L. A. van der Wielen,et al.  Thermodynamics in biochemical engineering. , 1997, Journal of biotechnology.

[4]  T. Brocklehurst,et al.  Modelling microbial growth in structured foods: towards a unified approach. , 2002, International journal of food microbiology.

[5]  L. Wadsö,et al.  Accelerated storage and isothermal microcalorimetry as methods of predicting carrot juice shelf-life , 2005 .

[6]  R. Vilu,et al.  Microcalorimetric study of the growth of bacterial colonies of Lactococcus lactis IL1403 in agar gels. , 2012, Food microbiology.

[7]  R. Vilu,et al.  Microcalorimetric study of growth of Lactococcus lactis IL1403 at different glucose concentrations in broth , 2009 .

[8]  A. Salumets,et al.  Growth characterization of individual rye sourdough bacteria by isothermal microcalorimetry , 2011, Journal of applied microbiology.

[9]  A. Schiraldi,et al.  Isothermal calorimetry approach to evaluate shelf life of foods , 2001 .

[10]  S. Higuchi,et al.  Gastric pH profiles of beagle dogs and their use as an alternative to human testing. , 2000, European journal of pharmaceutics and biopharmaceutics : official journal of Arbeitsgemeinschaft fur Pharmazeutische Verfahrenstechnik e.V.

[11]  L. Wadsö,et al.  Isothermal calorimetry for biological applications in food science and technology , 2009 .

[12]  Stanhope Bayne-Jones,et al.  BACTERIAL CALORIMETRY II. RELATIONSHIP OF HEAT PRODUCTION TO PHASES OF GROWTH OF BACTERIA , 1929, Journal of bacteriology.

[13]  L. Yi,et al.  Microcalorimetric investigation of the toxic action of Cd(2+) on Rhizopus nigricans growth. , 2000, Journal of biochemical and biophysical methods.

[14]  I. Lamprecht.  Calorimetry and thermodynamics of living systems , 2003 .

[15]  David A. Mitchell,et al.  A review of recent developments in modeling of microbial growth kinetics and intraparticle phenomena in solid-state fermentation , 2004 .

[16]  Katsutada Takahashi,et al.  Calorimetric Studies of Soil Microbes: Quantitative Relation between Heat Evolution during Microbial Degradation of Glucose and Changes in Microbial Activity in Soil , 1985 .

[17]  A. Ouwehand,et al.  Probiotics from an industrial perspective. , 2011, Anaerobe.

[18]  S. Salminen,et al.  Probiotics and health claims , 2011 .

[19]  H. Vandenhove.  Microcalorimetric Characterization of Bacterial Inocula , 1998 .

[20]  Delbert G. Carlson,et al.  Dog Owner's Home Veterinary Handbook , 1980 .

[21]  Frances E. Zollers,et al.  The European Food Safety Authority: Towards coherence in food safety policy and practice , 2004 .