A Study at the University of Florida took a look at tank cleaning foodgrade applications and determined that the procedures do not always meet the desired outcome, said Paul Winniczuk who conducted the study.
Winniczuk discussed the study at the National Tank Truck Carriers Tank Cleaning and Environmental Council Seminar March 30-31 in San Antonio, Texas.
In the tests using 176 tanks that had contained a variety of products, including juices, oils, milk, eggs, and peanut butter, Winniczuk determined that tanks continued to have bacteria in their interiors even with the university's controlled wash procedure. Samples were collected from throughout the tanks and from tank components.
However, Winniczuk pointed out that the study also determined several ways to improve cleaning results. Cleaning equipment should have correct assembly and alignment, cycle times are important, and the relationship of water flow rates to pressure should be appropriate.
Another example for improving results was to apply warm water and adequate soap concentration to reduce allergens on equipment found in domelids.
Winniczuk noted that tank parts can become contaminated after cleaning personnel handle them. In addition, tank components should not be placed in unclean areas after being washed.
Turning to clean-in-place systems, he said that leftover milk residue often can be detected in the tank after it has been cleaned. “What we have been doing for years may not be working properly,” Winniczuk added.