No one says that food products have to be sterile. At the same time, they must conform to the HACCP plan under which they are made. No manufacturer wants to introduce microbes that, for one reason or another, happen to be resident in a food manufacturing plant into the product. Sanitation strategy is concerned with eliminating, as much as possible, potential contaminant microorganisms that would otherwise be present in and around the environment a collection of ingredients must pass through in their transformation into the final retail product in its package and ready for sale.
One hears a great deal about various sanitation strategies. Unfortunately, one hears a good deal less about the actual sensitivity of microbes found in the plant environment to the various sanitation strategies under consideration. This may leave the impression that the sanitizing strategies involved kill all microorganisms equally and leave the treated environment completely free of viable microbes. Of course, this cannot be true. If it were, sanitation strategies would be called sterilization strategies.
At its most basic level, the importance of sanitation is that the process efficiently kill the actual microbes present in the plant itself. As mentioned elsewhere, a good place to sample the complete range of microorganisms present in the plant is from the air and common surfaces such as walls, floors, drains, etc., as well as any that may be cultivated from finished product. Having a stable of representative microorganisms is quite useful not only to determine risk (i.e., Hazard Analysis) but also because one may thereby also tailor-make a response (i.e., Critical Control Point) by direct quantitation rather then just using industry averages.
Microbes that have been allowed to rest upon plant surfaces for too long before sanitation is executed tend to form biofilms, a polymeric matrix in which microbes are embedded, which tend to protect any microbes embedded within from subsequent sanitation treatments. Microbes successfully embedded within a biofilm tend to become permanent residents. Removal of biofilms can be difficult.
Sanitation is often performed by the use of reactive chemicals (often purchased in liquid solution) toxic not only to life (microbial as well as plant personnel) but also destructive of the very manufacturing surfaces in need of sanitation. Such sanitizers are cheap, others are most definitely not. Environmental laws such as TSCA tend to significantly raise the cost of such chemicals as well as their cost of transportation. In addition, storing a sufficient amount of such toxic liquid chemicals on site is also not cheap, since extra costs may be involved in the construction of special storage areas, specialized training for use, monitoring, containment and, if needed, disposal.
Many food manufacturing facilities are in industrial buildings having exposed beams, rather crude ventilation systems and high ceilings. Part of the sanitation strategy development must include a consideration of a containment system such that only the enclosed space need be sanitized. This means that only the enclosed space need be tested, resulting in a tremendous cost saving. Furthermore, an enclosed space like this offers some unique sanitation possibilities. These may include radiation (ultraviolet light or ionizing radiation), heat, gaseous sanitizers (such as ozone generation or ethylene oxide exposure). These examples certainly do not exhaust the list of physical sanitizer solutions but their advantage to plant operations is quite obvious - whereas chemical sanitizers must rely upon a human operator for their application, the physical sanitation methods are more amenable to automation, which means not only a considerable savings in personnel but also that their dosage levels may be more reliably calculated. Realization of the cost savings attendant upon physical sanitation schemes require that representative samples of the microbial contaminants to be eliminated are on hand for the testing of sanitizer efficacy.
Another point to consider is that any unreacted sanitizer solutions used in the plant must also eventually leave the plant. Granted, most food production plants are already fitted with floor drains and these may seem like the ideal and convenient way to get rid of powerful chemicals. However, downstream of your floor drains you will usually find a waste water treatment plant. There, considerable time and trouble has been devoted to the establishment of biofilms within various flow-through devices because these are used to reduce the biological oxygen demand (BOD) of the influent. So, injection into this stream of compounds whose very design intent is to kill and disrupt biofilms will not go unnoticed by the waste water treatment facility whose facilities are thereby compromised.
As regulations get tighter and more demanding, technical creativity may have to be pressed into service to meet them. No one wants unsafe food. On the other hand, large and small food manufacturers must be able to make a profit, otherwise, why be in business at all? From the consumers point of view, safe food does no one any good if consumers cannot afford it. FSMA has put many new regulations on a horizon that is getting closer all the time. Some of the old ways of doing things may have to change.
Copyright © 2012 by M. Mychajlonka, Ph. D.