Spinoff of keeping crawfish thread - PURGING crawfish - ideas

First thing you'll need is a well, treated "city" water is going to kill them

Doesn't sound worth it for a crawfish boil, but I can see how a commercial business or restaurant could do it successfully.

[quote]First thing you'll need is a well, treated "city" water is going to kill them[/quote


Yep. Chlorine fricks em up.

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First thing you'll need is a well, treated "city" water is going to kill them

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yep, and a lot of mortons salt.

I'll go take some pictures of a commercial set up tomorrow and post

Info from the "Crawfish Production Manual" from LSU Ag:

Purging and Cleaning

To provide a more appealing product for live markets, a small number of producers have adopted the practice of “purging” crawfish before selling them. This requires that crawfish be confined in water or very humid environments where food is withheld for 24 to 48 hours. This process cleans the exoskeleton of mud and debris and eliminates or reduces digesta in the intestine (Figure 10.13), which consumers may find unappealing.

This method should not be confused with the practice of immersing crawfish in salt water immediately before boiling, which is not effective in evacuating the gut and is little more than an external wash.

To facilitate removal of the intestinal contents, crawfish are commonly held in tanks within specially constructed boxes or baskets (Figure 10.13) that are usually suspended in water.

Recommended loading rate is about 1.5 pounds of crawfish per square feet of submerged surface area with adequate aeration and water exchange.

Equally effective, but seldom used, is a water spray system where crawfish are held in shallow pools of water (1/2-inch deep) under a constant spray or mist. Holding crawfish in aerated vats or purging systems under crowded conditions for more than 24-48 hours is not recommended because of the possibility of excessive mortality.

Though purging increases the cost of the product, purged crawfish have high consumer acceptance, particularly outside of traditional Louisiana markets.

Some people who have eaten crawfish for many years are accustomed to non-purged crawfish and do not find them objectionable; nonetheless, many would probably prefer purged product if cost was reasonable.

Although the current market for purged crawfish is small from a lack of public awareness and price differences (15 percent to 25 percent higher), purging has contributed to repeat sales and loyalty to certain producers or distributors. Mortality during purging is the largest contributor to increased prices, but research has recently demonstrated that shorter purge duration (12 hours) can be nearly as effective and contributes significantly to less mortality.

The external surfaces of crawfish, which can be fouled and/or stained, are reasonably cleaned during purging. Abrasive actions of crowded crawfish rubbing against one another effectively “polish” the shells. For non-purged animals and excessively stained batches of crawfish, however, additional cleaning is sometimes accomplished prior to cooking. External cleaning of the carapace of live crawfish with food-service chemicals (ascorbic or citric acid and baking soda) to enhance appearance and increase marketability is becoming increasingly common.

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First thing you'll need is a well, treated "city" water is going to kill them

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So this is probably what would make it prohibitive for me. Is there anyway to filter out the stuff the city puts in it that is economical/feasible?

I guess I could just run down the road to Thompson Creek or the Mississippi and grab a couple gallons.

As somebody that had a bunch of fresh-water aquariums when I was a kid, you can either let the city water sit overnight or use anti-chlorinator to get rid of the chlorine. Easy as pie.

yellowfin,

Hope you don't mind me asking a few more questions re this.

1. You said they sit in the baskets and get resacked. In a previous thread a poster seemed to think the crawfish would kill each other if left unsacked for that long. I assume this is untrue?

2. These baskets look like they stay full submerged and the water is aerated well. Do you have any opinions on the water level being an inch or so and being aerated but without the crawfish being fully submerged being effective?