Time is how long is the cleaner in contact with the soil and the surface. Too short and the soil won’t be removed. Too long and you are wasting energy and have excess downtime and run the risk of redepositing. There is also a component of time to consider with respect to time between use and start of cleaning and time between cleaning steps. In the brewery, it is almost always easier (requires less time, action, cleaner, temperature, etc) to remove fresh wet deposits where there hasn’t been a chance for excess microbiological growth to occur than it it to remove the same deposit later. It all falls under time considerations.

What type of cleaning is being done? CIP with a spray ball? Is the ball fixed or rotating? Are you applying the correct flow rate/pressure? If a manual cleaning, do you use a hard brush, a soft scrubbie, or a towel/wash cloth? Are you spraying, power-washing, foaming, or gelling? Does your soak tank have any circulation/agitation? Ultra-sonic? While there can be a little variation in the action, it is usually set or dictated by the item being cleaned…you can’t set your 10bbl kettle in a soak tank — you’ve got to clean it CIP. At the same time, you may have an option to circulate at 30 gpm or 40 gpm. The key here is understanding what the action is going to be, and then making sure that it is working properly.

There isn’t one cleaner for every job. Knowing the soil, the surface, the temperature, and the action will help determine what cleaner will be most successful. Alkaline-based or acid-based? Foaming or low-foaming? The second part of the ‘C’ is concentration. You want to use the cleaner at the optimum concentration — neither too little or too much. The right concentration isn’t necessarily the highest concentration. It is the concentration that balances the process with the other parameters.

Cleaning is about getting the active parts of the cleaner to the soil on a molecular level without damaging the surface. One of the fascinating aspects of molecular chemistry, is that for every 10°F increase in temperature the number of molecular collisions in a liquid are doubled. This is an approximation, but is generally true. What it means to cleaning your brewery is that as the temperature of your cleaning solution is raised, there is a great increase in the number of times an unused ‘cleaner molecule’ collides with a ‘soil molecule’ on the surface and dissolves it into the water. Until and unless other factors dictate otherwise, the hotter a cleaning step can be performed, the faster it will get done — 160°F is better than 140°F, 180°F is better than 160°F. The cost of heating/maintaining the higher temperature works against this. So does the increased possibility of damage to your surface/side effects of some cleaners. And hotter cleaning solutions/rinses can evaporate and leave behind additional problems to deal with that a cooler solution wouldn’t. In the end, just as in choosing the ‘right’ chemical concentration is the key, its the ‘right’ temperature that you need.