Beyond a Bottle of Bleach

In today’s ever-changing food safety environment, food manufacturers strive to meet current regulations while balancing downtime and production efficiencies. Despite the critical importance of cleaning production equipment, the task is often undervalued. In some cases, the hierarchy of cleaning processes that could be implemented is misunderstood. Regardless of the size of the production plant, routine cleaning is required and must be factored into the master cleaning schedule and daily housekeeping activities.

There are different levels of cleanliness that food manufacturers should be familiar with and strategically implement. The minimum standard for cleaning is “visually” clean; however, this is simply removing food and debris from a surface to the extent that the human eye can see it. As any microbiologist will attest, what cannot be seen can and will still hurt you. So, what’s the next step in the process after removing the visual debris? This is where sanitizing and disinfecting come in. Having a solid understanding of some general principles will better equip plants with the ability to attain a higher level of clean.

Like many terms used in the industry, plant personnel can easily confuse sanitizing with disinfecting. So, what is the difference between the two? According to the FDA, “Sanitize means to adequately treat food-contact surfaces by a process that is effective in destroying vegetative cells of microorganisms of public health significance, and in substantially reducing numbers of other undesirable microorganisms, but without adversely affecting the product or its safety for the consumer.” In simpler terms, many experts say sanitizing kills 99.9% of bacteria and helps reduce its numbers to safe levels, while disinfecting goes even further and kills more microorganisms (including certain viruses and molds).

Many factors influence an effective safety and sanitation program, with the best approach generally being more complex than simply grabbing a bottle of bleach. Because not all sanitizers and disinfectants are created equally, a good starting point is knowing what you’re trying to clean and the options available for doing so.

Define the Target
Give primary consideration to the types of bacteria and other microorganisms you are targeting; this will help you determine whether you need to sanitize or disinfect. This information is usually found in the Hazard Analysis and Critical Control Points (HACCP) or food safety plan with the ingredient and process hazard analysis.

Many facilities use adenosine triphosphate (ATP) swabbing to start a historical record of general cleaning and will then often base cleaning frequencies on this documentation, using total plate count for additional information. Since most sites will not conduct pathogen testing on a product contact surface, the microbiological swabbing programs for zones 2 and 3 are often included in the risk assessment when determining whether to sanitize or disinfect.

Biofilms from the microorganisms must also be considered because they can act like a shield preventing the removal of the bacteria from the surface and thus play a part in the frequency of cleaning and sanitizing. If the microbiological risks are uncertain, resources offering guidance are available through agencies such as USDA, FDA, universities, chemical supply companies, and private food safety consulting and training firms.

Assess Your Options
Sanitizing and disinfecting can be completed in numerous ways, including through the use of heat, pasteurization, pressure, or irradiation, to name just a few. Another—and more accessible —way to complete sanitizing and disinfection is through the use of chemicals. Multiple factors will contribute to the process of choosing the most suitable chemicals to apply.

In selecting the right chemical, first consider whether the proposed sanitizer or disinfecting agent is authorized for use in a food processing facility. Often, over-the-counter home use chemicals contain perfumes, dyes, and inert compounds that are not authorized for a food processor. In the United States, sanitizers and disinfectants are regulated by EPA and must meet its criteria for labeling, storage, use, and disposal. Always refer to the chemical label and safety data sheet (SDS) directions for this information.

In addition, depending on your type of facility, these chemicals need to meet FDA and/or USDA regulations for food contact. You can get this authorization information from the chemical manufacturer through letters of guarantee and technical data sheets.

Also take into account whether the product is high risk or low risk, and whether the sanitizing or disinfecting process will occur pre- or post-kill step. The surface the chemical will be applied to must also be considered, as many chemicals can stain, degrade, or even react with the application area. Contact the equipment manufacturer and chemical supplier to determine which chemicals can be safely used on your plant’s equipment.

Another factor to keep in mind is bacterial resistance to chemicals. Many companies choose to rotate their sanitizers throughout the year to avoid such resistance. One example would be to go from a chlorine-based sanitizer to an acid or quaternary ammonia-based sanitizer.

Also remember that sanitizers and disinfectants both need contact time (called “dwell time”) and concentration levels to achieve their goal. Many high-concentration sanitizers and disinfectants need a potable rinse following application to adequately remove them from the contact surface, so consideration should be given to whether a no-rinse sanitizer is warranted.

To help ensure proper use, many sanitizers and disinfectants can now be purchased ready to use, while other chemicals may have to be manually diluted or placed in automatic dispensers and, in some cases, specific water temperatures are required for effective use. Some chemical supply companies can even custom blend chemicals to achieve optimum results. There are many options to choose from, so discussing specific requirements with a chemical supplier can aid in implementing a successful sanitizing and disinfecting program.

Safety determinations aside, other chemical choice restrictions may apply, such as those imposed by customers, religious protocols (e.g., kosher), or special certifications (e.g., organic). Many sanitizers can also be used as disinfectants if mixed at higher concentrations or allowed to stay on a surface for longer periods of time, so, if you want to minimize the number of chemicals on hand, choosing just one chemical to serve a dual purpose may be amenable. Usage directions on the chemical label can aid in such a decision.

What to Choose

Here are a few points and situations that may further direct your approach:
• Wash pit/equipment parts washroom: Because the smaller parts cleaned in these areas can be used throughout the plant, most sites use hot water with a general-purpose cleaner and a chlorine-based or quaternary ammonia-based sanitizer.
• Floor drains: Sanitizing and disinfecting floor drains is a must in a production environment. Many microorganisms can be found in these locations, which is why most plants use a strong sanitizer or disinfect drains. Because drainpipes and drain grates are not all made of the same material, it is important to identify the material and ensure that the sanitizing and disinfecting processes does not damage or erode them.
• Roof leaks: A roof leak potentially can carry very harmful microorganisms, so disinfecting the area of the leak is strongly recommended. Items used to contain or divert the leaks should also be on a disinfecting schedule. Since disinfecting does not kill 100 percent of microorganisms, many plants discard their diverters after the roof is repaired to avoid unintentionally providing an area for microorganisms to harbor.
• A one-production-line bakery making a single type of bread: Pre- and post-oven sections of the production environment usually do not have a large space to store chemicals. In this circumstance, a general-purpose sanitizer that can also be used as a disinfectant at higher concentrations and/or longer dwell time may be most practical. You can disinfect more frequently prior to the oven and less frequently after the oven due to the differing temperatures and, thus, distinct environments for microorganism growth.
• Manufacturer of ready-to-eat refrigerated dips with no kill step: A strong sanitizer, and sometimes a disinfectant, should most likely be used in this situation because the risk of microbiological growth is much higher in this type of operation. Since the product does not go through a cooking step (kill step), the cleaning and sanitizing processes are often conducted daily or more frequently to reduce the risk of contamination.
• Biohazards: Always use a disinfectant when there is a biohazard spill in your plant. Such a spill contains many additional microorganisms not usually associated with the production process, so you’ll need to give more attention to the spill than you would with a typical disinfecting scenario. Always be sure you have the appropriate disinfectant listed in your cleaning procedures to address these types of spills.

Ultimately, the determination of whether to sanitize or disinfect is a decision that must be made in coordination with the HACCP/food safety team, as changes to equipment, processes, raw materials, or ingredients will greatly affect the requirements. In addition, actively involving the chemical supplier or chemical manufacturer will help determine and address specific chemical needs. Keeping current with microbiological research is also necessary since new potential hazards and harborage areas are identified each year.

Every plant is unique and has individual sanitizing and disinfecting needs. The more personnel and information you involve in this discussion, the more likely it is that you’ll meet your sanitizing and disinfecting needs.

Zaher is manager of operations for the Americas at AIB International in Manhattan, Kansas. Reach him at [email protected].