Identification, Justification & Review
A critical control point is an intervention in the food manufacturing process made to ensure food safety. For example, no one wants to find glass shards, Salmonella or Listeria in their food. These are all food hazards. The "hazard analysis" portion of the HACCP plan should list these possible hazards and provide the likelihood of encountering each of these hazards in the food product made at a particular food manufacturing facility. If all the ingredients in this product have been repeatedly analyzed for glass and none were ever found and if the product, packaged into plastic pouches never encountered a glass surface during its production then one would be justified in assigning a negligible risk to the glass shard hazard. On the other hand, if this product was packaged into glass bottles, then a certain level of risk may exist. A critical control point would then be to have the bottling machinery tested (along with samples of the bottles to be used) to see if there is any propensity for glass to be knocked from the inside edge of the bottle containing product. A method would have to be devised to measure this risk and parameters set for what constitutes an acceptable risk and what does not. A quality control plot (described elsewhere in this site) could then be kept to answer the question of whether this critical control point was being adequately addressed.
Salmonella and Listeria are both bacterial pathogens whose presence or absence may be unpredictable from batch to batch. If their level is high or even if it is unpredictable, then these pathogens constitute a hazard the food manufacturer must contend with. However, either of these pathogens is quite easily killed by heat. Therefore, a critical control point for these hazards would be a heat-inactivation step. If such heat inactivation were extensive enough to kill 99,999 out of 100,000 such cells then the killing efficiency would be 99.999% or a so-called 5-log kill. This kind of critical control point is defined as "Pasteurization" by FDA. If the numbers of these pathogens a product had to begin with was very high, even a 5-log pasteurization may not suffice to produce a safe product (i.e., a risk of infection low enough to be considered reasonable). On the other hand, if the incidence of these (and all other) potential pathogens is know to be very low, then a 5-log pasteurization as a critical control point may be, quite literally, overkill. The decision might be made to save the cost of this energy-intensive step and heat only to a much lower kill rate, say, 3-logs instead of five. This may not only save processing costs but also result in a tastier and therefore more consumer-acceptable product. Such a product could not be labeled as "pasteurized" even though the product were safe according to the HACCP plan in effect.
The application of critical control points must be monitored during production. The time to measure the efficacy of this control point is not at the end of the process, when the concentration of bacteria may be expected to be low (and consequently the number of samples needed to accurately assess a small number of bacteria must be large). Rather, the best time to measure the efficacy of this critical control point (i.e. quality control) is before whatever heat treatment the manufacturer has chosen to use. Since the manufacturer must already know the rate at which these potential hazards are eliminated by the critical control point used and must also measure the parameters of the heating step applied to each batch, it becomes a simple matter to calculate the extent by which each of the potential microbial hazards of these two pathogens has been controlled.
This approach is favored by FDA, precisely because it is evidence-based. If a difficulty arises, such evidence for the product involved will be reviewed. If the evidence package is complete and shows that all product safety issues have been correctly followed, then the manufacturer has a strong defense. However, if the hazard analysis was incomplete, if the critical control points used were inappropriate or if HACCP was correctly planned but the quality control was flawed, in that it failed to show that all CCP's were correctly applied at all times, then the food manufacturer may have questions to answer.
Copyright © 2012 by M. Mychajlonka, Ph. D.