Microcalorimetric Study of Extruded Dog Food Containing Probiotic Micro-Organisms

摘要

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.