Low listeria levels in smoked fish due to controls, says SPSG
The UK's food safety regulator said that more than 3,000 samples of ready-to-eat hot and cold smoked fish were analysed to check for Listeria monocytogenes, the main type of listeria that causes illness in humans, between July and November 2006 from over 1,000 retail outlets in the UK.
While traces of Listeria monocytogenes were found in 302 samples, 99 per cent were within the legal limit for ready-to-eat foods, according to FSA.
Listeria is found naturally in the environment and can be present in a wide range of foods, from pâtés and soft cheeses to cooked sliced meats and smoked fish.
The regulator said that three hot smoked fish samples (0.06 per cent) breached the limits for L. monocytogenes laid down in the Microbiological Criteria Regulations and the agency confirmed it took immediate action to withdraw the products from retail.
In addition, the agency stated that no salmonella was detected in any of the samples tested but that it found variations in storage temperatures at retail ranging from -14°C to 13.3°C.
Controls in place
The SPSG, which comes under the umbrella of the UK's Food and Drink Federation (FDF), said that FSA’s findings come as no surprise to its members.
“Food safety is our sector’s number one priority and members of SPSG have been working hard over many years to ensure the right production controls are in place,” claims the association.
The SPSG told FoodProductionDaily.com that its members implement rigorous hygiene, safe handling and storage methods to help prevent the growth of any low levels of Listeria which might naturally be present:
“They monitor the raw material, process and product for Listeria and take appropriate preventative actions to minimise the risk of it occurring in smoked fish. Companies regularly review their production operations and follow industry best practice, which is fully communicated across the sector.”
Listeria cases ‘doubled’
According to the FSA, the reported number of illnesses from listeria in the UK has doubled since 2000, particularly in people over 60 years of age. In 2005, there were an estimated 400 cases, of which 380 people were hospitalised and 130 people died, making listeria the biggest cause of death from food poisoning.
Dr Andrew Wadge, chief scientist at the FSA said: 'Although only a snapshot of one type of food, this survey adds another piece to the listeria puzzle. We know cases are on the increase in the over-60s, but we don't know why.
“These findings suggest that, listeria isn't generally a problem in ready-to-eat smoked fish at point of sale – but it doesn't tell us what happens when people get it home.
"Are they preparing and storing food correctly and eating it within its 'use by' date? These and other questions are at the heart of further work we’re doing with our expert scientific committees to get to the bottom of this increase in listeria.'
The FDF said that on pack guidance for smoked fish products always states a ‘use by’ date (which is legally required), along with information to the effect that the product must be kept chilled and also instructions for home freezing and defrost.
The FDF said that it also recommends that SPSG producers should add guidance on how soon the product should be consumed after opening.
Plant cleaning methods
Meanwhile, researchers from the University of Nottingham, in a recent study, claim that meat factories may need to modify their cleaning and disinfecting procedures according to the type of meat product being processed to prevent food poisoning outbreaks.
The team claims that biofilms, which are bacteria that form communities on surfaces, are much more highly resistant to cleaning products and antibiotics.
In their opinion, bacterium such asListeria's success in persisting in processing environments comes partly from its ability to form resistant biofilms, and partly from its tolerance to drying out, thus enabling it to survive on ‘clean’ surfaces.
The researchers said that they also evaluated the influence of different cooked meat juices including beef, pork, lamb, chicken and duck on the attachment of Listeria to surfaces.
"We found significant differences between the ability of Listeria to stick to stainless steel surfaces at different temperatures, depending upon which meat was used,” said Professor Lisa Dodd. “Cooked duck juices at 25°C allowed the highest levels of Listeria attachment.”
