A survey of unopened ice cream, ice cream in use, and ice-cream-scoop
water (n=91) was
conducted to determine the effect of scoop water hygiene on the
microbiological quality of ice cream. An aerobic plate count around
106 c.f.u. ml−1 was the modal value for scoop
waters.
Unopened ice creams generally had counts around
103–104 c.f.u. ml−1
and this increased by one
order of magnitude when in use. Many scoop waters had low coliform counts,
but almost half contained >100 c.f.u. ml−1.
E. coli was isolated in 18% of ice creams in use, and in 10% of
unopened ice creams. S. aureus was not detected in any
sample. Statistical analysis showed
strong associations between indicator organisms and increased counts in
ice cream in use. EC
guidelines for indicator organisms in ice cream were exceeded by up to
56% of samples.