Fate of Escherichia coli O157:H7 during the manufacture of Mozzarella cheese.
OBJECTIVE
The fate of Escherichia coli O157:H7 was investigated during the manufacture of Mozzarella cheese.


RESULTS
The Mozzarella cheese was made from unpasteurized milk which was inoculated to contain ca 10(5) cfu ml(-1)E. coli O157:H7. Two different heating temperatures (70 and 80 degrees C), commonly used during curd stretching, were investigated to determine their effects on the viability of E. coli O157:H7 in Mozzarella cheese. Stretching at 80 degrees C for 5 min resulted in the loss of culturability of E. coli O157:H7 strains, whereas stretching at 70 degrees C reduced the number of culturable E. coli O157:H7 by a factor of 10.


CONCLUSIONS
The results show that stretching curd at 80 degrees C for 5 min is effective in controlling E. coli O157:H7 during the production of Mozzarella cheese. Brining and storage at 4 degrees C for 12 h was less effective than the stretching.


CONCLUSIONS
Mozzarella cheese should be free of E. coli O157:H7 only if temperatures higher than or equal to 80 degrees C are used during milk processing.
Spano
G
G
Institute of Alimentary Productions and Technologies, Agricultural Faculty, Foggia University, Institute Zooprofilattico of Apulia and Basilicata, Foggia, Italy.
Goffredo
E
E
Beneduce
L
L
Tarantino
D
D
Dupuy
A
A
Massa
S
S
D002611:Cheese / Q000382:microbiology*; D015169:Colony Count, Microbial; D019453:Escherichia coli O157 / Q000235:genetics / Q000254:growth & development* / Q000302:isolation & purification; D005516:Food Microbiology / Q000592:standards; D006358:Hot Temperature; D012965:Sodium Chloride / Q000737:chemistry / Q000378:metabolism; D013997:Time Factors
D012965:Sodium Chloride