“Cleanliness is next to godliness.”
Across the food industry, legions of plant sanitarians would swear they could comfortably retire if they had a sawbuck for every time they have heard this axiom. While battle fatigue associated with this oft-used adage is understandable, its underlying message—that effective cleaning and sanitizing are essential prerequisites for producing safe, quality food—remains at the core of sanitation training programs.
Sanitizers are generally defined as chemical, thermal, or radiation treatments that are used to disinfect, reduce, or mitigate the growth of microbial contaminates to levels that are considered safe from a public health standpoint. Under U.S. federal regulations, chemicals sold as sanitizers must kill 99.999% of 75 million to 125 million non-pathogenic Escherichia coli and Staphylococcus aureus bacteria during a 30-second exposure at 68°F.1
Due to their widespread popularity, chemical sanitizers are a critical component of plant sanitation programs. Accordingly, these programs should devote ample attention to providing employees with in-depth, continuous training on the proper handling, application, and intended use of chemical sanitizers, particularly those used on food equipment and other product contact surfaces.
Nationwide, the Environmental Protection Agency administers the registration of chemical sanitizers and antimicrobial agents for use on food product contact surfaces. Ideally, chemical sanitizers should:
- be approved for food contact surface application;
- have a broad range or scope of activity;
- be stable under all conditions;
- be tolerant of a broad range of environmental conditions;
- be readily solubilized and possess some detergency;
- be low in toxicity and corrosivity; and
- be inexpensive.2
Over time, the U.S. Food and Drug Administration (FDA) has sanctioned several chemicals for use as no-rinse, food contact surface sanitizers in the processing environment. The fact sheet “Basic Elements of Equipment Cleaning and Sanitizing in Food Processing and Handling Operations” offers an extensive review of commercially available chemical sanitizers.2 It was written by Ronald H. Schmidt, PhD, of the Food Science and Human Nutrition Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. The following section, highlighting excerpts from the fact sheet, provides a brief overview of some common industry sanitizers.
In its various forms, chlorine is the most commonly used sanitizer in food processing and handling applications. Commonly used chlorine compounds include liquid chlorine, hypochlorites, inorganic chloramines, and organic chloramines. “Chlorine compounds encompass broad-spectrum germicides which act on microbial membranes, inhibit cellular enzymes involved in glucose metabolism, have a lethal effect on DNA, and oxidize cellular protein,” Dr. Schmidt wrote. “The activity of chlorine is dramatically affected by such factors as pH, temperature, and organic load. The major disadvantage to chlorine compound is corrosiveness to many metal surfaces (especially at higher temperatures). Health and safety concerns can occur due to skin irritation and mucous membrane damage in confined areas.”
Widely considered as a chlorine replacement, chlorine dioxide (CIO2) appears to be more environmentally friendly and has 2.5 times the oxidizing power of chlorine. “ClO2’s primary disadvantages are worker safety and toxicity,” Dr. Schmidt wrote. “Furthermore, its highly concentrated gases can be explosive and exposure risks to workers is higher than that for chlorine.”
Dating back to the 1880s as an antimicrobial agent, iodine exists in many forms—known collectively as iodophors—usually with a surfactant as a carrier. Like chlorine compounds, iodophors are effective against a wide range of bacteria, viruses, yeasts, molds, fungi, and protozoa. “Iodine is highly temperature dependent and vaporizes at 120°F,” Dr. Schmidt wrote. “Thus, it is limited to lower temperature applications. The degree to which iodophors are affected by environmental factors is highly dependent upon properties of the surfactant used in the formulation.”
Quaternary ammonium compounds (QACs) are the only sanitizer group that has true residual activity. In some food processing facilities, QACs are used to sanitize equipment prior to long periods when the equipment is not in use. Effective against bacteria, yeast, mold, and viruses, QACs work over a wide pH range, with best activity in alkaline pH. They are generally more active against gram-positive than gram-negative bacteria. QACs are not highly effective against bacteriophages. QACs can be incompatible with certain detergents, making thorough rinsing following cleaning a necessity.
Acid-anionic sanitizers are surface-active sanitizers. “These formulations include an inorganic acid plus a surfactant and are often used for the dual function of acid rinse and sanitization,” Dr. Schmidt wrote.
Fatty acid (carboxylic acid) sanitizers were developed in the 1980s. “Typical formulations include fatty acids plus other acids (phosphoric acids, organic acids),” he wrote. “These agents also have the dual function of acid rinse and sanitization. Fatty acid sanitizers have a broad range of activity, are highly stable in dilute form, are stable to organic matter, and are stable to high temperature applications.”
Peroxyacetic acid (or peracetic acid, PAA) is effective against yeasts and molds. “Many large juice processors employ peroxyacetic acid for clean-in-place (CIP) applications.” PAA has been known for its germicidal properties for several years. “PAA is highly active against both gram-positive and gram-negative microorganisms. The germicidal activity of PAA is dramatically affected by pH. PAA solutions have also been shown to be useful in removing biofilms.”
Peroxides or peroxy compounds are divided into two groups. One is the inorganic group, which contains hydrogen peroxide (HP) and related compounds. The second is the organic group, which contains PAA and related compounds.
Predominately used in the medical field, HP has found limited application in the food industry. The FDA has granted approval for HP use for sterilizing equipment and packages in aseptic operations. “HP is fairly broad spectrum with slightly higher activity against gram-negative than gram-positive organisms,” Dr. Schmidt wrote. High concentrations of HP can cause eye and skin irritation.
Sanitation standard operating procedures (SSOPs) provide specific, written procedures necessary to ensure sanitary conditions in food plants. Many food company SSOPs contain extensive guidelines for the proper handling, storage, and usage of chemical sanitizers.
All too often in in-plant training programs, management will use these written documents to deliver all-important chemical sanitizer training to employees, usually in classroom settings. For members of the cleaning and sanitizing team, this outdated training mode fosters little interaction among participants—a universally acknowledged key to successful training—and can be highly tedious for both facilitators and students.
To avoid this training pitfall, food plants should actively seek to collaborate with their chemical suppliers to design and present continuous, on-site training programs. Growing numbers of chemical suppliers have dedicated education specialists who can conduct in-plant training on subjects ranging from proper chemical handling techniques to the importance of understanding labeling directions.
By nature, many chemical sanitizers are toxic, a fact that underscores the importance of proper personal protection equipment and sufficient knowledge for employees to protect themselves from simple workplace mishaps and major hazards.
Three vital factors—concentration, temperature, and contact time—affect the effectiveness of chemical sanitizers. The ability of employees, who often have varying educational levels and cultural backgrounds, to comprehend labeling instructions is critical in assuring that the manufacturer’s instructions are followed.
In today’s workplace, food plants struggle to find the time and expert resources to provide employees with all-inclusive, in-plant training. Building a relationship with chemical suppliers is a productive strategy for companies needing to support and improve their sanitation training initiatives.
Williams is senior communications specialist and Gonzalez is the director of technical services for Silliker Inc. Reach them at email@example.com.
- Marriot NG, Gravani RB. Principles of Food Sanitation. 5th ed. New York: Springer Science and Business Media Inc.; 2006.
- Schmidt RH. Basic elements of equipment cleaning and sanitizing in food processing and handling operations. Gainesville, Fla.: University of Florida Institute of Food and Agricultural Sciences Extension; 1997. Available at: http://edis.ifas.ufl.edu/FS077. Accessed October 21, 2009.