Influence of long-chain polyphosphate and heat treatment on Clostridium cochlearium and Clostridium sporogenes isolated from processed cheese spread.
The outgrowth of Clostridium spp. spores causes spoilage in processed cheese products due to gas and off-odor formation. The present study focuses on the response of spores of Clostridium sporogenes and Clostridium cochlearium at 25 degrees C to polyphosphate, both alone and in combination with heat treatment. The two strains used were isolated from spoiled cheese spread. The addition of 1.5% polyphosphate but not 0.75% polyphosphate totally inhibited the growth of C. sporogenes SIK4.3; in contrast, 0.75% polyphosphate was sufficient to totally inhibit C. cochlearium CCUG 45978. The highest polyphosphate concentration tested (1.5%) was sporicidal for C. sporogenes SIK4.3 but not for C. cochlearium CCUG 45978. When 0.75% polyphosphate Bekaplus FS was combined with a holding time of 5 min at 98 degrees C, no survival or growth of C. sporogenes SIK4.3 was detected; however, the same effect was not achieved through heating alone or through application of polyphosphate alone. C. cochlearium CCUG 45978 was more heat tolerant, as shown by higher D-values. In conclusion, the results strongly suggest that polyphosphate Bekaplus FS has the potential to restrict the growth of C. sporogenes and C. cochlearium in cheese spread stored at ambient storage temperature. Experiments with cheese are needed in order to verify this effect.
Borch
Elisabeth
E
SIK (The Swedish Institute for Food and Biotechnology), Ideon Research Park, SE 223 70 Lund, Sweden. elisabeth.borch@sik.se
Lycken
Lena
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D002611:Cheese / Q000382:microbiology*; D003013:Clostridium / Q000187:drug effects* / Q000254:growth & development; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D004305:Dose-Response Relationship, Drug; D005506:Food Contamination / Q000032:analysis*; D005519:Food Preservation / Q000379:methods*; D006358:Hot Temperature; D006801:Humans; D011122:Polyphosphates / Q000494:pharmacology*; D013045:Species Specificity; D013171:Spores, Bacterial / Q000254:growth & development; D013997:Time Factors
D011122:Polyphosphates