Hello Kajumon,
I have used Perasan and of course, also chlorine. They both have advantages and disadvantages as everything. Chlorine of course is inexpensive and effective, but need to be used at correct PH so an acid should be added to the water (in wash tanks) to maintain proper pH. Peracetic acid is not pH dependent and can be used in waters with more organic loads, it cost a little more but as per my experience, has better log reduction. Also, Peracetic acid is very strong and corrosive when concentrated, resulting in higher worker risk for the employees, but since the dilution rate is lower than chlorine, once diluted it is actually less corrosive for the equipment than chlorine. (be sure to used pumps for acid)
You are going to have a lot of questions when selecting a chemical for controlling bacteria in wash water. Here is my advice:
· Do not see this step as a “killing Step”: Regardless of the chemical, the ability of killing bacteria in the surface of the produce if not a proven fact, it may reduce it but not eliminate it. The sanitizer will kill bacteria IN the water controlling possible cross contamination.
· Do not decide based on what the salesperson tells you: They all have the best product and will tell you how it is approved by USDA, FDA and used by NASA. You may search for scientific studies on that specific sanitizer for your specific product and see what you find. If you are lucky enough to find one, you can use that paper as validation in most cases.
· Make your own test (validation): This is the most important!! What may work for some, may not work for you. All plants are different in product, equipment, process, water quality, etc. Inform the sales person that you are going to make a validation, buy few product (55 gallon drum or less) and run some tests. What I normally do is send produce samples before going thru the wash and after the wash to a lab to be tested for APC (Aerobic Plate Count). That way you can see the actual reduction in bacteria count with each sanitizer for your specific product, equipment and process. Do this first with the product you are currently using, that way you can compare. An finally, while doing this take some numbers on the COST as well, how much sanitizer per gallon or per hour (however you can measure it) is used and what is the cost. That way you can do a cost/benefit analysis.
Hope this help. Good Luck!