Establish Effective Sanitizer Concentrations and Contact Times
Measure Microbial Reduction to Demonstrate Efficacy
Incorporate Sanitation Protocols into a Comprehensive Food Safety Plan
A key component of an effective food safety program is a robust sanitation program outlined in Sanitation Standard Operating Procedures (SSOPs) and includes aspects of both cleaning and sanitizing. Surfaces are first cleaned in order to remove debris and organic soils that can impact the effectiveness of sanitizing agents. Sanitizers are then applied using concentrations and contact times effective for inactivation of microorganisms that could remain on the surface after cleaning.
Establishing Effective Concentrations and Contact Times
A number of sanitizing agents are commonly used in food production and foodservice environments, including quaternary ammonium, hydrogen peroxide, organic acids, chlorine-based agents such as sodium hypochlorite or more novel formulations and technologies. The effectiveness of sanitizing agents can be evaluated using in vitro (test tube) testing to validate lethality using time-kill assays or to establish Minimum Inhibitory Concentrations (MIC) of an antimicrobial. This is also a straightforward and useful way to compare baseline efficacy of different sanitizers, concentrations or exposure times against microorganisms of concern and decide what works best for you.
Since surface materials, cleaning materials (cloths, paper towels), application procedures and removal (e.g., wiping) techniques vary in food processing environments, experimental protocols can also be designed around these variables to test the efficacy of your sanitizer in a more representative application. This type of testing is intended to mimic the sanitation procedures actually used in your plant to measure reduction of bacteria on food contact or non-food contact surfaces. For example, microorganisms may be inoculated onto a stainless steel surface and then sprayed and wiped using your procedures to measure the effective reduction of the target organism.
Guidelines for Sanitizer Efficacy
In general, the minimum reduction to be considered an effective sanitizer according to EPA is 99.9% within 5 minutes on nonfood-contact surfaces or 99.999% within 30 seconds on food-contact surfaces (OCSPP 810.2300). Variance in these guidelines is typically related to the type of sanitizer used or the specific application. The EPA Product Performance Test Guideline for Santizers also makes recommendations for test microorganisms to study (for example, E. coli and S. aureus for food-contact surfaces) although sanitizer manufacturers or food processors may desire or need to validate efficacy against additional microorganisms to address specific biological hazards or food safety concerns. The testing protocols used for efficacy testing can incorporate a range of contact times and concentrations in order to establish effective application procedures to meet these guidelines.
Putting it to Practice
Verifying the efficacy of sanitizers against target microorganisms is one key step to preventing contamination in your product and processing environment but does not stand alone. Once the required application strength and time are known, this information will be incorporated as an aspect of the broader SSOPs that protect your consumers and employees. A robust food safety program will identify hazards associated with your production line and seek to control these hazards, with effective sanitation being a critical component of the process. A hazard analysis will incorporate an evaluation of all hazards, including those that are microbiological, physical and chemical in nature, so in addition to proving that a sanitizing agent is effective, it will need to be assessed to ensure it does not introduce a chemical hazard into the process.
Ongoing monitoring of sanitizer concentrations and schedules may be necessary and the effectiveness of the overall program can be monitored through routine swabbing and an environmental monitoring program. The goal of testing environmental swabs is to verify that your sanitation practices are effective, but you can start at the beginning by understanding what to expect of your sanitizer and then verify your program from start to finish.