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Etude de l'irradiation gamma de poudres alimentaires éffets sur la microflore aérobie de l'amidon

Study of the gamma irradiation of powdered foodstuffs: Effects on the aerobic microflora of starch

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Summary

The microbicidal effects of γ-irradiation on the microflora of starch have been investigated. Large variations were observed in the total numbers (up to 7.106 per 1g of mesophilic aerobes) as well as types (1 to 15) of bacteria encountered. The most abundant groups appeared to beBacilli, Micrococci andPenicillia. Enterobacteriaceae were only seldomly isolated. The only pathogen isolated was aStaphylococcus.

Inactivation curves in starch were determined for “total” floras (mesophilic aerobes, mesophilic and thermophilic spore-formers, moulds) and 40 pure cultures. These curves show considerable variation in patterns and levels of resistance. Hypotheses are given to explain the various patterns of inactivation. The established levels of resistance are in agreement with liberature data. A very radioresistantMicrococcus was isolated (LD90=750 Krad). However, the group presenting most problems is that ofBacillus spores, because of their frequency, thermo- and radioresistance, and the possible enterotoxicity of some strains (B. cereus). From survival rates obtained with spore-formers at various No values, a diagram for the radiopasteurisation of starch is derived. It results in over-dosing starch when it is lightly contaminated, owing to a so-called dispersion effect.

Resume

Cette étude a pour objet d'évaluer l'efficacité des rayons γ pour la désinfection d'une poudre alimentaire: l'amidon. Elle comprend d'une part, l'analyse qualitative et quantitative de la microflore d'amidons industriels, d'autre part, l'établissement de courbes de survie pour les flores totales et certaines souches pures susceptibles de créer des difficultés par leur fréquence, leur pouvoir pathogène ou leur radiorésistance élevée. Un microcoque pigmenté en rose formant des tétrades a été isolé. Il présente une résistance comparable à celle deM. radiodurans. Néanmoins le groupe le plus préoccupant est celui desBacillus. Un barème indicatif tenant compte de leur résistance est proposé pour la radiopasteurisation de l'amidon.

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Bibliographie

  1. Anderson,A.W., Nordan,H.C., Cain,R.F., Parrish, G., Duggan, D. (1956). Food Technology10, 575–578

  2. Anderson,A.W. (1969). Irradiation inactivation of food infection microorganisms in seafoods. In: Freezing and irradiation of fish. R.Kreuzer, Ed. London: Fishing News Ltd.

  3. Anellis,A., Berkowitz,D., Kemper,D. (1973). Appl. Microbiol. 25, 527–523

  4. Berger,G., Saint-Lèbe,L. (1971). C. R. Acad. Sc. Paris 272, 1455–1458.

  5. Briggs,A. (1966). J. Appl. Bact.,29, 490–504

  6. Burt,M.M., Ley,F.J. (1963). J. Appl. Bact.,26, 484–489

  7. Christensen,E.A., Holm,N.W. (1964). Acta Pathol. Microbiol. Scand.60, 253–264

  8. Comer,A.G., Anderson,G.W., Garrard,E.H. (1963). Can. J. Microbiol.9, 321–327

  9. Dyer,J.K., Anderson,A.W., Dutiyabodhi,P. (1966). Appl. Microbiol.14, 92–97

  10. Grecz,N. (1966). Theoretical and applied aspects of radiation D-values for spores ofClostridium botulinum. In: Food irradiation, IAEA, Vienna, SM 73/67, 307–320

  11. Hill,E.C., Philips,G.O. (1959). J. Appl. Bact.22, 8–13

  12. Krabbenhoft,K.L., Anderson,A.W., Elliker, P.R. (1965). Appl. Microbiol.13, 1030–1037

  13. Lewis,N.F. (1971). J. Gen. Microbiol.66, 29–35

  14. Ley,F.J., Winsley,B., Harbord,P., Keall, A., Summers, J. (1972). J. Appl. Bact.35, 53–61

  15. Miller,D.L., Goepfert,J.M., Amundson,C.H. (1972). J. Food Sci.37, 828–831

  16. Morgan,B.H., Reed,J.M. (1954). Food Res.19, 357–366

  17. Moseley,B.E.B. (1967). J. Gen. Microbiol.49, 293–300

  18. Mossel,D.A.A. (1963). J. Appl. Bact.26, 398–404

  19. Mossel,D.A.A., de Groot,A.P. (1965). The use of pasteurizing dose of γ radiation for the destruction ofSalmonellae and otherEnterobacteriaceae in some foods of low water activity. In: Radiation preservation of foods. Publ. 1273. Washington D.C. Nat. Aca. Sci.-Nat. Res. Council

  20. Mossel,D.A.A., Ratto,A. (1970). Appl. Microbiol.20, 273–275

  21. Sainclivier,M., Roblot,A.M. (1966). Ann. Inst. Pasteur Lille17, 181–187

  22. Spicher,G. (1957). Zbl. Bakt. Abt. II,110, 153–171

  23. Spicher,G. (1960). Zbl. Bakt. Abt. II,113, 666–671

  24. Stapleton,G.E. (1955). Ann. N. Y. Acad. Sci.59, 604–618

  25. Thornley,M.J. (1963). J. Appl. Bact.26, 334–345

  26. Underbal,B., Rossebø,L. (1972). J. Appl. Bact.35, 371–377

  27. Wesley,F., Rourke,B., Darbischire,O. (1965). J. Food Sci.30, 1037–1042

  28. Wheaton,E., Pratt,G.M. (1972). J. Food Sci.27, 327–334

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Etude effectuée dans le cadre d'une action concertée entre les organismes suivants: Commissariat a l'Energie Atomique Société Roquette Frères, F-62136 Lestrem C.E.R.T.I.A. Et financée par la: Délégation Générale à la Recherche Scientifique et Technique (Contrat No 747002)

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Delattre, J.-., Fretton, J.-., Fretton, R. et al. Etude de l'irradiation gamma de poudres alimentaires éffets sur la microflore aérobie de l'amidon. European J. Appl Microbiol. 1, 259–280 (1975). https://doi.org/10.1007/BF00930699

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