Stabilité microbienne et enzymatique des boissons à base de jus de fruits et de lait traitées grâce à des champs électriques à intensité élevée pulsée ou grâce à la chaleur pendant l'entreposage frigorifique.

Microbial and enzymatic stability of fruit juice-milk beverages treated by high intensity pulsed electric fields or heat during refrigerated storage.

Auteurs : SALVIA-TRUJILLO L., PEÑA M. M. de la, ROJAS-GRAÜ M. A., et al.

Type d'article : Article

Résumé

The influence of high intensity pulsed electric fields (HIPEF) treatment (35 kV/cm, bipolar 4 ms square wave pulses at 200 Hz) on the inactivation of Listeria innocua in fruit juiceewhole (FJeWM) or skim milk (FJeSM) beverages was assessed. As well, the effects of HIPEF or conventional thermal (90 _C 60 s) processing in terms of microbial and enzymatic stability and changes on physicochemical parameters of the beverages during refrigerated storage were also studied. HIPEF and thermal processing ensured the microbial stability of the beverages during 56 days at 4 _C without significant changes on pH, acidity and soluble solid content values. Thermal processing was more effective than HIPEF in reducing Pectin Methyl Esterase (PME) activity in FJeSM and FJeWM beverages since its activity was reduced by 70.66% and 87.33%, respectively. With regards to Polygalacturonase (PG), HIPEF treatment reduced by 26.92% and 20.93% the enzyme activity in the FJeWM and FJeSM beverages, respectively, whereas thermal treatment did not inactivate PG in both beverages. HIPEF or thermally-treated samples showed higher viscosity than the untreated ones, being this increment more pronounced in the beverages with whole milk. Therefore, HIPEF processing may be a feasible technology in order to obtain shelf stable and freshlike fruit juice-milk beverages.

Détails

  • Titre original : Microbial and enzymatic stability of fruit juice-milk beverages treated by high intensity pulsed electric fields or heat during refrigerated storage.
  • Identifiant de la fiche : 30002425
  • Langues : Anglais
  • Source : Food Control The International Journal of HACCP and Food Safety - vol. 22 - n. 10
  • Date d'édition : 10/2011
  • DOI : http://dx.doi.org/10.1016/j.foodcont.2011.03.022

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