An evaluation of HACCP implementation status in UK small and medium enterprises in food manufacturing.

To reduce foodborne illnesses, hazard and risk-based quality management systems are essential. Small and medium sized companies (SMEs) tend to have a poor understanding of such systems and limited adoption of the Hazard Analysis Critical Control Point system (HACCP). The requirement for full HACCP implementation by 2006 will place an even greater burden on these businesses. The aim of this project is to assess the current levels of understanding of hazards and risks in SMEs in the manufacturing sector. A questionnaire survey was made of 850 SMEs, including microbusinesses. This determined the industry sector and processes carried out, whether the company operated hazard-based quality management and the knowledge of the technical manager regarding the associated hazards and risks. Follow-up visits to the manufacturing plant observed the processes and the operatives to determine their level of understanding. A benchmarking audit was carried out and each company was rated. The results show that the majority of respondents stated that they operated hazard analysis-based quality management. The ability of the respondents to correctly define a hazard or risk or identify different types of hazard was, however, poor. There was no correlation between business type and audit score. The microbusinesses did, however, perform significantly less well than the larger SMEs.

Growth of Listeria monocytogenes and Yersinia enterocolitica colonies under modified atmospheres at 4 and 8 degrees C using a model food system.

The growth of Listeria monocytogenes and Yersinia enterocolitica colonies was studied on solid media at 4 and 8 degrees C under modified atmospheres (MAs) of 5% O2: 10% CO2: 85% N2 (MA1), 30% CO2: 70% N2 (MA2) and air (control). Colony radius, determined using computer image analysis, allowed specific growth rates (mu) and the time taken to detect bacterial colonies to be estimated, after colonies became visible. At 4 degrees C both MAs decreased the growth rates of L. monocytogenes by 1.5- and 3.0-fold under MA1 (mu = 0.02 h(-1)) and MA2 (mu = 0.01 h(-1)), respectively, as compared with the control (mu = 0.03 h(-1)). The time to detection of bacterial colonies was increased from 15 d (control) to 24 (MA1) and 29 d (MA2). At 8 degrees C MA2 decreased the growth rate by 1.5-fold (mu = 0.04 h(-1)) as compared with the control (mu = 0.06 h(-1)) and detection of colonies increased from 7 (control) to 9 d (MA2). At 4 degrees C both MAs decreased the growth rates of Y. enterocolitica by 1.5- and 2.5-fold under MA1 (mu = 0.03 h(-1)) and MA2 (mu = 0.02 h(-1)), respectively, as compared with the control (mu = 0.05 h(-1)). At 8 degrees C identical growth rates were obtained under MA1 and the control (mu = 0.07 h(-1)) whilst a decrease in the growth rate was obtained under MA2 (mu = 0.04 h(-1)). The detection of colonies varied from 6 (8 degrees C, aerobic) to 19 d (4 degrees C, MA2). Refrigerated modified atmosphere packaged foods should be maintained at 4 degrees C and below to ensure product safety.

Evaluation of two methods for monitoring surface cleanliness-ATP bioluminescence and traditional hygiene swabbing.

The minimum bacterial detection limits and operator reproducibility of the Biotrace Clean-Tracetrade mark Rapid Cleanliness Test and traditional hygiene swabbing were determined. Areas (100 cm2) of food grade stainless steel were separately inoculated with known levels of Staphylococcus aureus (NCTC 6571) and Escherichia coli (ATCC 25922). Surfaces were sampled either immediately after inoculation while still wet, or after 60 min when completely dry. For both organisms the minimum detection limit of the ATP Clean-Tracetrade mark Rapid Cleanliness Test was 10(4) cfu/100 cm2 (p < 0.05) and was the same for wet and dry surfaces. Both organism type and surface status (i.e. wet or dry) influenced the minimum detection limits of hygiene swabbing, which ranged from 10(2) cfu/100 cm2 to >10(7) cfu/100 cm2. Hygiene swabbing percentage recovery rates for both organisms were less than 0.1% for dried surfaces but ranged from 0.33% to 8.8% for wet surfaces. When assessed by six technically qualified operators, the Biotrace Clean-Tracetrade mark Rapid Cleanliness Test gave superior reproducibility for both clean and inoculated surfaces, giving mean coefficients of variation of 24% and 32%, respectively. Hygiene swabbing of inoculated surfaces gave a mean CV of 130%. The results are discussed in the context of hygiene monitoring within the food industry.

The effect of electron beam irradiation, combined with acetic acid, on the survival and recovery of Escherichia coli and Lactobacillus curvatus.

The preservation of food by ionising radiation may lead to undesirable sensory changes within the food. These changes can be reduced by combining irradiation with other treatments, for example the addition of organic acids. Late exponential phase cultures of Escherichia coli and Lactobacillus curvatus were irradiated, in a liquid medium, at doses of 0-1.8 kilograys (kGy), in the presence of acetic acid (0-2%) at pH 4.6. A synergistic effect occurred when E. coli was irradiated in the presence of acetic acid (0.02-1.0%) at all doses used (0.145-1.1 kGy). There is evidence to suggest that membrane disruption occurred in the cells as a result of the combined treatments and this may account, to some extent, for the synergism observed. The addition of acetic acid up to a concentration of 2.0% had no effect upon the radiation survival or upon the subsequent growth of L. curvatus.

The effect of electron beam irradiation and modified pH on the survival and recovery of Escherichia coli.

The severity of radiation processing can be reduced by combining irradiation with other treatments, such as low pH. An exponential phase culture of Escherichia coli was irradiated at doses of 0-2.4 kGy at pH values ranging between 7.0 and 4.0, in an enriched nutrient broth. At pH 4.3 and above there was no significant effect of lowering the pH prior to irradiation. At pH 4.13 and 4.0, a much higher level of cell death occurred compared with irradiation at pH 7.0. This synergistic effect was observed only when the pH was lowered before radiation processing.