Overnight, during shutdown, your bottling plant accumulates bacteria and algal spores. They float in through the doors as people leave or become dislodged from roof areas by draughts. By the morning the washer/filler is contaminated.
Rather than start up with a contaminated washer, it is becoming good practice to disinfect the machine before operations begin. Ideal for this purpose is treatment with a fine spray of hydrogen peroxide. There is no need to rinse afterwards and there will be no problems with taint. It is important to wear a face mask and face shield during this operation, to protect eyes and avoid inhalation of the fine spray.
Hydrogen peroxide at ready-to-use concentration is available or a more concentrated product is available in 25L containers for use with a venturi spray system.
An alternative approach is to use sachets of chlorine dioxide-generating materials. The sachets are placed in water and the chlorine dioxide gas evolved disinfects the washer/filler and surrounding area.
Yet another option is to use peracetic acid. This is normally delivered at 5% concentration and requires dilution down to a use concentration of 0.5% of the 5% product (about 250ppm). In each case, the disinfectant should be allowed to work for a period of 10-15 minutes before start up.
It is good practice to rinse the pipe line from the holding tank to the filler with disinfectant solution before start up (make sure to rinse).
For general disinfection of floors and walls use a mixed quaternary product because this has a residual effect which continues to work overnight.