How to Clean and Sanitize
in an Organic Food Production Facility

By Dennis Bogart


With the growing number of operations in the organic sector and the need for all food manufacturers to clean and sanitize, knowing what cleaning methods and sanitizing treatments can be used to meet both regulatory requirements and the National Organic Program (NOP) standard is crucial. The primary cleaning and sanitation goal for both conventional and organic food processors is the same: assuring the food safety and wholesomeness of the final product. No company wants to make the consumer sick, or worse, cause death. According to estimates by the Centers for Disease Control and Prevention (CDC), approximately 75 million consumers in the U.S. get food poisoning each year, and between 5,000 and 15,000 die each year from doing little more than having lunch.

If the goal of cleaning and sanitation is to make sure that the food is safe, the question then is, safe from what? Currently, the most significant safety concern is microbial contamination of foods, which can be broken down into three broad groups of bacteria. These groups include microbes that will spoil the product (spoilage organisms); pathogenic bacteria that cause foodborne illness; and bacteria that are used to actually manufacture food, such as in cultured type products. Of these groups, spoilage organisms and pathogens must be controlled. Often, the first line of defense in eliminating harmful microorganisms in the plant is the food company’s sanitation program.

There are two overriding sanitation principles common to both conventional and organic processing operations. The first is that a food processing surface is either clean or it is dirty. There is no such thing as “kind of clean” or “sort of clean enough.” If it’s not clean, it’s dirty, period. The second principle is that you cannot sanitize a dirty surface. It is physically and chemically impossible. Thorough cleaning will remove about 90-95% of microbes from the surface. The job of the sanitizer is to eliminate the vast majority of the remaining organisms, although it is important to understand that sanitizers do not kill everything.

A commonly held standard for successful sanitation in both conventional and organic processing stipulates that no more than one or two microbes per square centimeter of surface area remain on processing equipment or other food-contact surfaces. The distinguishing feature of the organic processing plant’s sanitation aim is the need to eliminate or minimize any contamination of the product with the cleaners and sanitizers themselves. This makes the selection of appropriate cleaning methods, sanitizing agents and chemical treatments a critical factor for the organic food production facility.

Organic Cleanup, Pure and Simple
Cleaning and sanitizing are two completely separate operations within a food sanitation program, but both must be performed in tandem in order to successfully achieve food safety and quality assurance goals. Cleaning is defined as the use of mechanical agitation and detergents to remove visible soil, biofilms and other residuals from the surfaces of equipment, floors, walls, etc. Sanitizing is the application of chemicals or chemical treatments to remove remaining bacteria or residuals that cannot be seen with the naked eye.

Cleaning. Most of the complex cleaners available on the market today contain synthetic detergent versus natural soap. This is because synthetic detergents clean far better than a natural soap, in effect “lifting” dirt from the surface for better washing. More importantly, they rinse far better than a natural soap, thus eliminating residuals from the surface. A good example of poor rinsing of a natural soap is a typical bathtub ring: The harder the water, the worse the residual condition develops making it impossible to rinse. Since it is likely that a synthetic detergent will be used, the post-rinse becomes an important step in cleaning in an organic processing facility.

How do you tell if the surface is thoroughly rinsed? A good indication is the measurement of any residual alkalinity or acidity in the rinsing solution or on the surface using pH as a control, or by using various chemicals such as phenolphthalein to tell if there is any residual detergent left on the surface. If there is any residual alkalinity left on the surface, phenolphthalein dropped onto the surface will turn red. By rinsing until there is no more red color when phenolphthalein is dropped onto the surface, there is assurance that little or no residual of the cleaner remains on the surface.

The equipment used to clean surfaces is another important consideration. Mechanical agitation is key to lifting dirt from a surface. The buckets, brushes and scrub pads themselves can affect the success of your cleaning efforts. For example, white scrub pads are far less abrasive than green scrub pads, and as such, tend not to scratch stainless steel whereas green pads will. Brushes and buckets need to be color-coded to prevent potential cross-contamination from clean areas to dirty areas of the plant or raw to cooked.

Sanitizing. Once a surface is clean and thoroughly rinsed, the organic food processor needs to consider the sanitizing step, specifically the types of sanitizers that are acceptable for use in an organic food plant and which of these will effectively control the remaining microbes left on the surface following cleaning. It is extremely important that any sanitizer used in a U.S. food processing plant is registered as food contact surface sanitizer by the U.S. Environmental Protection Agency (EPA). There are some products that are marketed and sold as sanitizers or disinfectants, but without proper registrations their use in a food plant is in violation of federal law. Another factor to consider is that in the U.S., Canada and Mexico, with very few exceptions, it is illegal to rinse the sanitizer off the surface. We deal with a method of sanitizing called “terminal sanitation,” which means that the sanitizer is left on the surface, drained or dried, and then the food is processed on that surface. Because of this, there is a distinct possibility that the food could be contaminated with the sanitizer—an obvious issue for the organic processor.

The typical sanitizers that are considered inappropriate for organic processing are those that are based on synthetic surfactants, most of which are oil- or coal-based products. Sanitizing agents that fall within this category are quaternary ammonium (quat), iodine and acid anionic sanitizers. Products that do not contain synthetic surfactants are peroxyacetic acid (PAA), ozone and chlorine sanitizers. All three of these are very effective sanitizers and have various acceptable applications in organic processing.

Chlorine is a halogen-based chemical that attacks proteins and is extremely effective in eliminating microorganisms from surfaces. Chlorine is frequently used in food processing plants because it is inexpensive. It is a sanitizer that organic processors can choose to use, but should consider reducing or eliminating from their sanitizer toolbox. Although it is considered a “naturally occurring” chemical, chlorine is corrosive to stainless steel and metals used to construct processing equipment. If equipment is corroded, leaving pits, cracks or other niches in the surface, you can’t clean it thoroughly. Again, if you can’t clean it, you can’t sanitize it. Chlorine also poses a potential hazard to workers because if accidentally mixed with other chemicals, it creates a toxic chemical gas. In addition, chlorine is not environmentally friendly. It will form trihalomethanes (THMs) as a waste product in the sanitation streams or sewers, which have been linked as a cause of cancer in humans.

Unlike chlorine, the other sanitizer options suitable for organic processors typically are more expensive, but they are far more environmentally friendly products that offer excellent sanitizing results. When peroxyacetic acid breaks down in the sewage treatment system, it will eventually form water and oxygen, for example, while ozone breaks down to form oxygen as its “waste” product. Both peroxyacetic acid and ozone kill microbes in the same way: They are strong oxidizers that attack proteins—not only the food that the microbes eat, but the microbial cell walls. These sanitizers do not act with finesse; they are hackers and slashers that literally rip the cell walls of microorganisms apart, including their DNA.

Peroxyacetic acid is a combination of hydrogen peroxide, acetic acid (vinegar) and a minute amount of stabilizer that form a strong oxidizing agent. These sanitizers are effective against all microorganisms, including spoilage organisms, pathogens and bacterial spores. Characterized by a strong odor, you may want to use these sanitizers in well-ventilated areas. Peroxyacetic acid solutions are effective over a wide pH range and can be applied in cool or warm water to all food contact surfaces in the plant.

Ozone is a form of oxygen that consists of a three-atom molecule (O3). Ozone-enriched water kills microbes as effectively as chlorine, and since it is generated on-site, its use eliminates the need for personnel to handle, mix and dispose of harsh chemicals for sanitation. Ozone readily reverts to oxygen, an end-product that leaves no residue on contact surfaces. Ozone-enriched water can be sprayed directly on floors, drains, walls, processing equipment, tanks (externally and internally), and clean rooms via mobile or centralized systems with hand-held or drop-down, low-pressure sprayers. The U.S. Food and Drug Administration (FDA) has recently approved the use of ozone as a sanitizer for food contact surfaces, as well as for direct application on food products to reduce microbial loads.

In order to kill microorganisms, the sanitizing treatment must physically touch the bacteria. If any microbes that remain on the surface are covered in soil, the sanitizer can’t get to them. One of these soils is biofilm, where spoilage organisms and/or pathogens have covered themselves in a slimy, polysaccharide film on the surface of processing equipment or other plant surfaces. Thus, it is important to sanitize immediately after cleaning. If you wait and too much time elapses between the cleaning and sanitizing steps, the remaining bacteria will immediately start to cover themselves. Good cleaning will remove biofilms but not all microbes from the surface, because some microbes are attached to the surface and will not come off that surface unless a sanitizer is used. If your processing equipment is enclosed (i.e., tanks or lines), the food manufacturer has a two- to four-hour window in which to clean and sanitize before biofilming becomes an issue. If the equipment is open, the time frame is closer to 15 to 30 minutes before you would have to re-sanitize. In many processes, if the production line is down on weekends and the plant is cleaned and sanitized on Fridays, you should re-clean and re-sanitize before the start of production on Monday.

Finally, all sanitizers have a range of use strengths and their labels will provide direction as to appropriate applications. To help reduce sanitizer residuals, organic processing operations should use the minimum allowable strength of any sanitizing agent they select. This is truly a case in which more is not better.

Strategic Sanitation
The various philosophies about cleaning and sanitizing are relatively simple—in theory. They are not so simple in practice. The plant environment—floors, walls, ceilings, exteriors of each piece of equipment and especially, drains—must be cleaned and sanitized. Each of these areas must be included in a master sanitation schedule and routinely cleaned. This will go a long way to control Listeria and Salmonella, which are typical environmental contaminants.

Since people are a source of such microbial contamination, the processor also should strongly consider setting up microbial barriers in a plant for critical areas. These barriers are specifically designed to control contaminants on our hands and feet. Controlling foot traffic to prevent cross-contamination between production areas is a good way to achieve this, particularly through the use of floor foamers. Peroxyacetic acid is effective in a floor foamer, along with quats. (However, quats are only recommended for floors in organic food plants, not product contact surfaces.) Using foam cleaning for environmental sanitation of floors, walls and exteriors of equipment is very good, and spraying these areas with ozone or peroxyacetic acid sanitizers on a periodic basis is also effective.

Following the basic steps of cleaning and sanitation is the best strategy to ensure the safety and quality of the products manufactured in the organic processing facility. Beginning with the selection of appropriate cleaning and sanitizing agents from recognized suppliers, these steps include a good pre-rinse of equipment and plant environment, a thorough washing with a good detergent, a very thorough rinsing with validation of that rinsing, and sanitizing with one of the three sanitizers mentioned. By using this approach, the organic processor will produce a good, wholesome product that people will want to buy again and again and again.

Dennis Bogart is a senior consultant with Randolph Associates in Birmingham, AL. He has a M.S. in food technology from Texas A&M and has more than 30 years experience in the food industry dealing with sanitation, microbial and quality issues. He may be reached at dennislbogart@aol.com.