How do industrial kitchens thoroughly wash all dirt off of fresh herbs in the most efficient way possible (minimizing water use)?
Example: I have 20 kilos of fresh cilantro to wash to make a tomato salsa. The cilantro is full of dirt, so I want to make it completely dirt-free while using as little water as possible.
What tools and process would an industrial kitchen use to clean fresh herbs in bulk?
most farms that I use, use an agitator and a spinner. the agitator is a vat of water with high volume air bubbles introduced to gently agitate the herbs and jostle the dirt. this can refresh the slightly desiccated green, and be done for a long time. they follow with putting them in a cloth bag, and getting it into a portable unheated dryer for spinning- the model ive seen is probably a ten-ish gallon dryer. Again, its an unheated spin dryer- no heater.
I don’t know about ‘completely dirt free’, but putting leafy things into a large amount of water, agitating them, then lifting them out leaves much of the dirt and debris in the water.
If you let the water sit for a while, the solid matter will mostly fall to the bottom. You can then either do a new batch and risk stirring the dirt on the bottom, or you can decant it (pour or siphon off to the cleaner water on top to separate it from the dirt)
If the water gets too dirty for your liking, you can change it, or wash everything once, change the water, then wash it again in a clean change of water.
And you can repurpose any dirty water to water plants, rather than just sending it down the drain.
(Note: I am not a professional, so they may have some other redommendation)
With such large amounts of herbs, I think Joe's answer is a good start. I would "rough wash" the herbs first by swirling them in a large container like a 10-20l plastic food container filled with water, getting the bulk of earth and dirt off, then "fine wash" in a second large container, then finally using a salad spinner to dry the herbs and remove small particles along with the rest water, as outlined in this article from SeriousEats. Change water as needed between batches.
If the herbs are large enough and your quantity is large, run them through the washing machine several times on gentle. This beats them up a bit, but I do my mustard greens like that all the time. I don’t see why it wouldn’t work with herbs if you have a lot.
