Richard,
I never encountered any problems with pathogenic bacteria out-growth in
phosphate solution. I think that without any organic load it is not
particularly hospitable environment for them including bacteriostatic
properties of some phosphates. Certainly, the phosphate concentration and
additional presence of salt in the solution, if any, are also factors since
they would reduce water activity. Besides, please note, that your food
contact surfaces in a wetfish processing plant would create much more
conducive conditions for the bacteria than the phosphate solution itself.
What do you mean by 'dosing tanks'? Are they simply what we used to call
Calgon drums or something else? If they are soak tanks through that the
product is being conveyed and the content replaced only periodically, then
it would be advisable to look at any bacteria status that may come from both
cumulation and multiplication. But in known to me phosphate soak tanks the
solution was refrigerated through simple heat exchangers, mechanically
filtered and UV light treated before being fully recirculated.
Andrew Strak
Canadian Fishery Consultants Limited
www.canfish.com
----- Original Message -----
From: Richard Chivers
To: seafood
Sent: Thursday, April 27, 2000 7:54 PM
Subject: HACCP, phosphate solution
I am carrying out a safety orientated HACCP evaluation of a plant and in
particular a system that requires the production of phosphate solution to
reduce drip loss in frozen block of fillets.
The process uses mains water drawn into a stainless steel tank and
refrigerated. Into this is mixed phosphate in powder form. The solution is
mixed, then pumped to an unrefridgerated holding tank then pumped again to
an unrefrigerated dosing tank. The solution is all used during one day's
production (10 hours). The filters in the pumps are cleaned twice daily and
the three tanks are cleaned at the end of each day. The solution is added
to cod fillets, which are immediately (5 mins) boxed and plate frozen.
The product is used by another processor for the manufacture of fish fingers
and like products.
I have not come across any problem with similar systems in the past and the
company's own records of 10 years show no safety issue with the product
although pumps used previous to the new filtration system are reported to
have built up E.coli.
I am interested to know if anyone has identified, or heard of incidences, of
bacterial contamination in similar circumstances. In particular I question
the filtration system, it must generate heat and have pockets that are not
cleaned as frequently as the actual filters.
Any views would be gratefully received.
This archive was generated by hypermail 2b29 : Fri Apr 28 2000 - 16:59:47 PDT