Despite an intensified government control of food production in the industrial countries the incidence of food-relatet diseases is incraesing year after year. In the majority of dignosable cases, food from canteen kitchens is identified as causative agent. Food from Bundeswehr kitchens is also time and again established as a cause of disease among mess food participants. The percentage of cold meals as regards identified causes of diseases amounts to approx. 50 percent. The purpose of this paper was to effect a hygiene hazard analysis and to determinate "critical control points" in the preparation of cold meals in Bundeswehr food service facilities. To this end, in-process controls of the preparation of cold meals were conducted in three different Bundeswehr unit kitchens on 28 days over a period of 2 years. The dishes examined comprised 6 sausage, 2 beef and 8 chicken salads, 3 curd cheese desserts, 2 cremes and 7 boiled puddings. During the in- process controls measurements of the ambient temperature and of the core temperature of the food were conducted. Samples of 140 initial, intermediate and final products were taken and mikrobiological tests were conducted to identify the total number of aerobic bacteria as well as changes in the germ spectrum (Enterobacteriaceae, enterococci, staphylococci, Bacillus cereus). Apart from this, the mikrobiological status of appliances and utensils used during the preparation of meals (n=87) was determined. Moreover, 41 samples were taken from surfaces in order to verify cleaning and disinfection measures. The microbiological examination of the food followed the test procedures of the Official Compilation in accordance with § 35 LMBG (German Food Act) (L 06.00.16, L 06.00-19, L 06.00-25, L 06.00-32). The microbiological status of surfaces was identified by means of the "Quantitative swab method" in accordance with DIN 10113-1. By summary evaluation of the results the production process was recorded and hazards in the production process were identified. Possibilities for installing "control points" and "critical control points" in accordance with the HACCP concept for risk minimizing were considered. On the basis of results obtained, two "critical control points" could be established: The storage of the primary products and the cooling down of heat- treated food prior to its further processing. At these points, the elemination of potential hazards can be accomplished by time/temperature controls. Throughout all other phases of the preparation process several complementary hygiene control measures need to be combined in order to eliminate microbiological hazards, this rendering the term "critical control points" inapplicable. An effective process control is, however, ensured by adherence to the following hygiene control points:
1. On-receipt inspection of foods, 2. Exclusive use of pre-cooled products, 3. Preparation of cold meals and other meals at different places or at different times, 4. Processing without delay and preparation shortly before food dispensing, 5. Avoiding manual contact by use of disposable gloves or kitchen tools; unavoidable manual contact only after thorough hand cleaning and disinfection, 6. Provision of microbiologically clean surfaces of appliances and utensils disinfection in accordance with detailed hygiene plans. Wiping and desinfecting by means of a cloth produced irregular and often insuffcient results in the kitchens. Moreover, even after thorough cleaning, both manually and in a dishwasher, Makrolon tops still exhibited high numbers of germs and hygiene indicator germs. Only disinfection led to a mikrobiologically satisfying condition. As a consequence, the hygiene plans to be developed should - in deviation from established Bundeswehr hygiene regulations - provide for a daily disinfection of such tops and shelves. Current regulations call for disinfections on a weekly basis only. Micobiological examinations of the surfaces are essential to verify successfully performed cleaning and disinfection measures. Visual inspections alone are not sufficient. In order to determine the germ content of surfaces the wet/dry swab method as per DIN 10113-1 was validatet for a certain type of swab in preliminary tests and in field trials compared as a reference method with the simple swab procedure and various commercial agar contact systems with regard to applicability and validity (n=242). The reference method produced the highest retrieval rate in comparing tested procedures. Yet, because of complicated sampling and elaborate processing it seems to be only conditionally suitable for routine examinations. The simple swab method, which allowed for easier sampling, yielded a germ result wich was 0,5 log10 steps lower and had a good correlation with the reference method (r=0,82). In addition, the combination of this simple swab procedure with the Millipore sampler makes the treatment of samples less complicated. The germ numbers determined by means of agar contact systems were on average one log10 step lower than the values determined by the reference method
