The key to safe products with desirable a shelf life often comes down to the level of sanitation within the processing plant. An elevated level of sanitation equals wholesome products meeting customers’ wants and needs. Poor sanitation equals unhappy customers and loss of sales.

When I first started working in a dairy plant, Richard Nixon was president and it cost me 36 cents per gallon to put gasoline in my car. We cleaned the dairy using flake caustic soda and sanitized with hot water or chlorine. A 14-day shelf life was considered excellent for fluid milk. My, how things have changed.

In today’s world, the shelf life of fluid milk exceeds 21 days for high-temperature/short-time pasteurization and can exceed 60 days for extended-shelf-life and aseptic processing. We have myriad chemical cleaners and sanitizers from which to choose and technologies such as ATP testing to evaluate the cleanliness of equipment.

Yet some things remain the same. Clean is still clean; dirty is still dirty. And we still have not developed an effective way to sanitize dirty equipment. Sanitation is still the most critical process in a dairy plant operation. Effective cleaning and sanitizing of equipment and environmental surroundings are still essential. Sanitation remains the first step in dairy processing to produce high-quality and safe products for consumers. 

Basics for success

Today, most dairy plant operations are highly sophisticated with automated clean-in-place (CIP) systems and well-designed processing equipment. The success or failure of a sanitation program, however, is often dependent on those old-fashioned manual and clean-out-of-place (COP) methods. Let's look at some of the very basic procedures that are necessary for success.

Manual Cleaning is the simplest type of cleaning. It requires some basic practices.

  1. Equipment must be completely disassembled for cleaning on a surface dedicated for washing parts. 
  2. All equipment must be pre-rinsed with warm water (100 to 120 degrees Fahrenheit) before scrubbing.
  3. Parts are then scrubbed in hot water (110 to 120 degrees Fahrenheit) in a cleaning solution, using the right cleaning chemicals at the proper usage level.
  4. Once they are clean, the parts are rinsed with warm water and stored on a clean surface or in sanitizer.

COP Cleaning may be used on parts that cannot be effectively cleaned by CIP. COP cleaning involves more than just “boiling” the parts in a washtub.

  1. A cleaning solution — using the proper cleaner, concentration, temperature, time, and flow — is a basic requirement for COP cleaning. Solution concentration, temperature, flow, and cleaning time must be documented.
  2. As with manual cleaning, all parts must be pre-rinsed and disassembled prior to going into the COP tank. All parts and pipes must be completely submerged in the cleaning solution.
  3. The proper COP tank must be used for cleaning. Push-pull models circulate water from the ends and are used for cleaning long pipes. Side-circulating models produce a corkscrew flow and are used for cleaning various parts such as elbows and valves.
  4. Once cleaning is completed, the tank should be rinsed and overflowed, and sanitizer should be added. 

CIP Cleaning, like manual and COP cleaning, is dependent on the application of the basic principles of cleaning: time, temperature, velocity, and chemical concentration. While CIP systems are automated, it is critical that these parameters are monitored each time the system is used. The effectiveness of CIP cleaning is dependent on the proper application of these four principles. Automated systems do fail; thus, they must be monitored by properly trained individuals.

Environmental cleaning and monitoring is the fourth practice that cannot be overlooked. The overall environment of the facility must be cleaned and sanitized on a regular basis. These procedures are performed as scheduled and monitored with a robust swabbing program. Remember: A dairy plant and its equipment are either dirty or clean. Following these four best practices is the first step to producing high-quality, wholesome dairy products in your facility. Properly maintained equipment and trained people are essential to an effective sanitation program.

Tedd Wittenbrink is technical director for Merieux NutriSciences.