Order of chemical usage

[Seangoloid]

I'm just curious about everyone's opinion on the order of chemical usage for CIP applications. I've always been a fan of the caustic, rinse, acid, rinse, sanitize protocol. I'm just curious if anyone thinks that there might be any advantages to running an acid cycle before the caustic cycle (of course rinsing between cycles).
I know that running the caustic cycle first will help denature organic materials. I don't know if there are any advantages to running an acid cycle first, except for a conversion coating or saponification cycle... but that's a different story.

Cheers!
Sean

[gitchegumee]

The "acid first" protocol is championed by Dana Johnson at Birko. He's got papers published that explain the chemistry. I think you could google it to read them. I've tried it and it does seem to remove beerstone more effectively. I don't practice it now because I find that the using the acid after the caustic removes the tenacious caustic more effectively than just water rinsing the caustic. Or non-caustic alkaline detergents, too. But there are many ways to clean a tank and there are many factors. I do not use an alkaline wash on our 12 serving tanks in a cold room. Instead, I use an acid detergent designed for cold cleaning in a pressurized CO2 environment. Saves time, CO2, energy, chemicals, and water. And I only caustic wash the mash tun a few times a year. Otherwise my mash tun is hand cleaned every brew day and stays clean and bright without the need for chemicals. Kettle also comes clean easy enough with a quick brushing, although I do chemically clean it every 3-5 batches. Fermenters are where I stay old school and caustic-rinse-acid-rinse-sanitize every time I use them. Always like to hear what else might work elsewhere! Let us know what your experiences are with this system if you decide to give it a try. Cheers!

[HinduKush]

Dana's paper covers acid first as it pertains to Birko's non-caustic cleaner, Bru-R-Ez. I was skeptical years ago but swear by it and have converted many of my brewer friends. Acid Bight #2, dump, no rinse, Bru-R-Ez, rinse. Saves time and skrilla.

[dick murton]

If I have picked up the article you are referring to, then he is talking about more or less one off descaling, not regular cleaning.

If you use this method as a regular sequence in a CIP set, then you will end up using far more acid, at greater cost than conventional caustic, rinse acid etc, because the acid becomes so heavily soiled it has to be dropped more often, or because you use it as a one shot system.

Once descaled, and providing you are using formulated detergents, then caustic / rinse / acid etc is a more cost effective method.

I would still give plant a caustic clean before acid then caustic descaling as suggested, simply to remove the proteins from the surface of the scale - allowing the acid / caustic combo to work on a "clean" surface of scale.

If you always dump both caustic and acid, then there may not be much difference in cost between the two sequences, though I suspect that you could use less material if cleaning scale free plant with caustic then acid.

Acid cleaning only of filtered beer bright beer tanks is very common, but still useful to be able to caustic clean once or twice a year, just to get rid of any protein build up that does sometimes occur.

[MikeS]

I've found the caustic, rinse, acid, rinse, sanitizer to be best order for most CIP situations in the breweries I've worked in.

One exception is in the brew kettle. I can't explain the chemistry, but empirically, running acid first on the kettle for the weekly CIP (water rinse between brews) produced a much cleaner vessel. My working theory was that the acid broke up the (inorganic) kettle deposits and allowed the caustic to work more effectively on the organic matter.

The kettle always had a dull look when cleaned the "traditional" way. Using acid first left the kettle shiny inside.

Just one data point...

-Mike