Temperature Control Of Fridges

Hi!

I would like to know if there is any reference stating that ready to eat or high risk foods can be stored at chiller temperatures upto 8^oC (taking into account the 7 D Salmonella kill during cooking at >75^o C and < 100 L. monocytogenes / gram of food and no increase in B. cereaus) which can control the growth of pathogenic bacteria that may be present in the ready to eat foods, so that a target level of 5^oC can be set especially, during the very busy operational hours in a catering industry, where the shelf life of all high risk foods is only 72 hours.(There is no cross contamination as the GHP and SSOP are followed).

Regards,

J

The law leads the way in the UK. 8 degrees is acceptable by law, although most establishments will target 5. It is important to know that Listeria will still grow (albeit slowly) at both temperatures.

EU law basically says you should target 10 cfu/g or less in ready to eat food. 100 seems high and if you are getting Listeria at all, it is worth looking at the processes if you can. It will occur in fresh produce, even after washing but there are ways of controlling it. Having said that, the law in the EU also considers food which has 5 days or less shelf life to 'not be able to support the growth of Listeria monocytogenes' and so the legal limit for these foods in the UK is 100 cfu/g, however, if you were getting results like that, your customer would not be happy. It's also worth considering that some specialists think that limit is high.

I think in summary, you're best aiming for 5 or below but you need to look at how often you exceed that and why. One time I audited a catering operation, I found sandwiches at 10 degrees in a chilled display. In the end I found out it was because the display was only designed to be chilled on the bottom shelf.

(By the way, I ended up throwing away 50% of the stock of that canteen on that audit. Believe it or not, people started to try and argue!)

Dear GMO,



Thanks a lot for your reply.

100 seems high and if you are getting Listeria at all, it is worth looking at the processes if you can.

The issue in this case is not the presence of Listeria or the counts. Contamination with high numbers of L.monocytogenes at retail is rare if the GMP's are followed. As per the Gulf standards it is zero-tolerance. To my knowledge there is no internationally acceptable level for L.monocytogenes. Please correct me if I am wrong.

In foods that permit growth, the control measures such as temperature control or limiting the shelf life will reduce the increased risk. In re-formulated foods (altering pH below 4.4value, organic acids, freezing or Aw below 0.92) the chances to support growth are less.



My case here is the chiller temperatures are targeted for below 5^oC, but due to frequent opening and closing during the busy operations it tends to fluctuate between 5^oC and 8^oC for an hour or so in a shift roughly. However the samples have been tested for microbiological analysis and we had acceptable results. The foods are used within 72 hours after preparation.



At the moment, I am in search of a reference standard that states foods can be stored up to maximum of 8^oC so that during any inspections or audits this can be my reference for justification



You are right, some display chillers have chilling unit from bottom and these are mainly used for cakes. In case, sandwiches are used then it will be displayed at the bottom and also for maybe 4 hours and in small quantities.



The following extracts are from the link below:-



http://www.fao.org/DOCREP/003/X3018E/X3018E06.HTM

The detectable presence of L. monocytogenes in ready-to-eat food is considered to be a hazard to health under current US FDA policy. The limit of sensitivity of the analytical method is actually 1 cfu per 25 g (0.04 cfu g-1). In Canada foods have been placed into 3 categories, based upon health risk. Products in Category 1 have been causally linked to outbreaks of listeriosis and receive the highest priority in inspection and compliance activities. Currently, there are no fishery products included in this category. Category 2 contains all other ready-to-eat foods which are capable of supporting growth of L. monocytogenes and have a shelf-life exceeding 10 days (in this category the action level is absence in 25 g). Category 3 contains two types of ready-to-eat food products; those supporting growth with a < 10 day shelf-life and those not supporting growth. These products receive the lowest priority in terms of inspection and compliance action. For Category 3 ready-to-eat foods, factors such as the presence or absence of Good Manufacturing Practice (GMP), levels of L. monocytogenes in the food (action level of 100 cfu g-1) and/or a health hazard evaluation are all considered in the compliance action taken

In Denmark, ready-to-eat foods have been placed into six categories where absence of L. monocytogenes in 25 g is required in heat treated foods and in otherwise preserved, not heat treated foods that are capable of supporting growth within the shelf-life. This level is necessary in foods capable of supporting growth, in order not to exceed 100 L. monocytogenes per gram at the point of consumption. In heat treated and preserved foods that do not support growth within the shelf-life and for raw, ready-to-eat foods, a level below 10 L. monocytogenes g-1 is regarded as acceptable, a level between 10 and 100 g-1 is not satisfactory and a level above 100 g-1 is not acceptable.

The International Commission for Microbiological Specifications for Foods (ICMSF) states that sampling of food for microbiological testing and the use of criteria are insufficient to ensure food safety. However, these tools are useful as part of the verification programme to ensure that the HACCP-plan is working. Thus, according to ICMSF, for:

• in-pack, heat-treated products – no testing is necessary (documentation for the heat-treatment process);
• raw products and/or products which are to be heat-treated before consumption – no testing is necessary;
• ready-to-eat products, unable to support growth of L. monocytogenes – 10 samples should be taken and the lot should be rejected if any sample contain > 100 L. monocytogenes g-1;
• ready-to-eat products, able to support growth of L. monocytogenes – 20 samples should be taken and the lot rejected if any sample contains > 100 L. monocytogenes g-1.

More recently, international criteria for L. monocytogenes have been discussed by a Working Group of the Codex Committee for Food Hygiene. This Working Group agreed to propose to the Codex Committee on Food Hygiene to recognize that numbers of L. monocytogenes not exceeding 100 g-1 in food at the time of consumption is of low risk to the consumer. Furthermore, with respect to imported foods, it agreed to recommend that lower levels may need to be applied at the port-of-entry for foods that support the growth of L. monocytogenes, in order not to exceed 100 cfu g-1 at the point of consumption.

Regards,

J