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Hello, please tell me how you humanely dispatch your tilapia for the table.  When I googled it, some said using ice chokes them, others say shock them (?) others say drive a pin through their skull, or hit them in the head with a hammer.  Wow, I can't picture myself chasing flopping fish with a hammer!  I just want to do the job without causing the fish too much pain.  I also think when something is being killed, it can put out body chemicals (kind of like we have coritsol) because of fear.

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Yes, that sounds right, David,  Does it take days for the stress chemicals to be out of their body? I wonder if it's the same for us, after we drive in traffic etc.  No wonder many of us are sick!  The research showed photos of lesions in the fish flesh after harvest stress. 

On another note, I'm reading people withhold food from the tilapia for a few days before harvest for a cleaner taste. Should we do that?  


David - WI said:

You're talking about a pretty small amount of clove oil that's put into the water for only about 10 -15 minutes prior to harvesting the fish; I don't think there's any way that even a "detectable" amount of clove will make it into the meat/flesh of the fish.

I think a big consideration is that in order to reduce the stress and stress reactions in the fish; the water that you put them in to anesthetize them should have the same temperature, pH, DO level, etc as the water they just came out of... or better yet capture and move them to a smaller tank 4 or 5 days before you plan to harvest them so all the "stress" chemicals from handling them have dissipated, then quietly sedate them and so you can harvest them without any additional stress.

Sunny Oettel said:

HOWEVER, hmmm, if we do plan to eat the fish, does anyone know any Cloved Tilapia recipes?? In other words, I wonder if it would make the fish taste like cloves? 

The next trick will be trying to catch fish in that big ole 275 ga container!

Sunny Oettel said:

Yes, that sounds right, David,  Does it take days for the stress chemicals to be out of their body? I wonder if it's the same for us, after we drive in traffic etc.  No wonder many of us are sick!  The research showed photos of lesions in the fish flesh after harvest stress. 

On another note, I'm reading people withhold food from the tilapia for a few days before harvest for a cleaner taste. Should we do that?  


David - WI said:

You're talking about a pretty small amount of clove oil that's put into the water for only about 10 -15 minutes prior to harvesting the fish; I don't think there's any way that even a "detectable" amount of clove will make it into the meat/flesh of the fish.

I think a big consideration is that in order to reduce the stress and stress reactions in the fish; the water that you put them in to anesthetize them should have the same temperature, pH, DO level, etc as the water they just came out of... or better yet capture and move them to a smaller tank 4 or 5 days before you plan to harvest them so all the "stress" chemicals from handling them have dissipated, then quietly sedate them and so you can harvest them without any additional stress.

Sunny Oettel said:

HOWEVER, hmmm, if we do plan to eat the fish, does anyone know any Cloved Tilapia recipes?? In other words, I wonder if it would make the fish taste like cloves? 

Wow, Bob, it is admirable that you would take the time to write an article for the sake of those creatures that have no voice.  I'm a little scared if I as a girl would be strong enough to kill them with the first blow? Is there anywhere that explains where on the head is most effective?  I'm leaning towards using the Clove Oil first in the water, to minimize the unnecessary preparatory stress to the fish AND me.  I will then need to use some method to dispatch them.  The swift blow may be the best--because they could regain consciousness in the ice water before death--then more stress, adrenaline, cortisol in the fish.  I've seen actual pictures of what the stress does to the meat quality, along with the animal's undue suffering. 

Wow, Bob, I watched the video you had at the bottom of your article on Clubbing a Fish. That was NOT quick and easy. How do I avoid THAT mess? 

Bob Campbell said:

Last year I too had questions about dispatching my fish in a compassionate manor.  I spent a fair amount of time researching the topic and wrote an article [LINK].

I use a 1" dowel about 16" long to club my tilapia.  The easiest way I've found is to hold the fish in the net so that they don't slide out of your grasp.  Wait a moment until they settle down and make one swift blow to the top of the head.  Death is instantaneous.  There is no suffering, no blood, it's just a good clean kill,.

My article contains hyperlink to validate the methods. Here is a condensed summary of what I found in my research.

Inhumane and totally unacceptable slaughter methods, that can take a long time for
fish to lose consciousness and die, should be prohibited urgently. These include
suffocating fish in air or on ice, bleeding to death without pre-stunning, and the use of
carbon dioxide for stunning.


Only slaughter methods that cause an instant death or render the fish instantly
insensible to pain until dead should be permitted. These include percussive stunning
techniques whereby fish are rendered instantly unconscious when carried out
efficiently.

Here is a web address (I don't know how to make it an active link) to some pictures that show what happens to the quality of stressed fish, and compares it to the flesh of fish not stressed:  http://www.aqui-s.com/index.php/harvest-management

Sunny Oettel said:

Wow, Bob, it is admirable that you would take the time to write an article for the sake of those creatures that have no voice.  I'm a little scared if I as a girl would be strong enough to kill them with the first blow? Is there anywhere that explains where on the head is most effective?  I'm leaning towards using the Clove Oil first in the water, to minimize the unnecessary preparatory stress to the fish AND me.  I will then need to use some method to dispatch them.  The swift blow may be the best--because they could regain consciousness in the ice water before death--then more stress, adrenaline, cortisol in the fish.  I've seen actual pictures of what the stress does to the meat quality, along with the animal's undue suffering. 

Wow, Bob, I watched the video you had at the bottom of your article on Clubbing a Fish. That was NOT quick and easy. How do I avoid THAT mess? 

Bob Campbell said:

Last year I too had questions about dispatching my fish in a compassionate manor.  I spent a fair amount of time researching the topic and wrote an article [LINK].

I use a 1" dowel about 16" long to club my tilapia.  The easiest way I've found is to hold the fish in the net so that they don't slide out of your grasp.  Wait a moment until they settle down and make one swift blow to the top of the head.  Death is instantaneous.  There is no suffering, no blood, it's just a good clean kill,.

My article contains hyperlink to validate the methods. Here is a condensed summary of what I found in my research.

Inhumane and totally unacceptable slaughter methods, that can take a long time for
fish to lose consciousness and die, should be prohibited urgently. These include
suffocating fish in air or on ice, bleeding to death without pre-stunning, and the use of
carbon dioxide for stunning.


Only slaughter methods that cause an instant death or render the fish instantly
insensible to pain until dead should be permitted. These include percussive stunning
techniques whereby fish are rendered instantly unconscious when carried out
efficiently.

be careful with clove oil. From the missed-link earlier.

"AQUI-S is a pharmaceutical derivative that contains 50% active ingredient and is registered for use with food fish in New Zealand and Australia with a nil withdrawal period. However, neither anesthetic is approved for use with fish in North America. "

 

and from the FDA (LINKAGE)

Although clove oil and some of its components are generally recognized as safe (GRAS) for use in dental cement or as food additives, neither clove oil nor any of its components are GRAS for use as an anesthetic for fish. 

Because some clove oil products may contain or include either methyleugenol or isoeugenol, or both, CVM is concerned that the use of clove oil or its components in fish may adversely affect human food safety and animal food safety. This concern especially applies to the use of Clove Oil or any of its components in fish intended for use in human or animal food 

Hey - would a fish-guillotine be humane enough? Just watch your fingers!

I harvested my White Tilapia just this past weekend using the ice bath method. I purchased a 20 lb bag of ice, put it in a large cooler and added water. Do about half of the ice until all the water is in. Add the rest of the ice and a lot of the ice should remain during the harvest process. (I didn't know about adding salt to the ice bath...probably would have reduced the slimyness.) My tank is a 750 gallon stock tank. I had 6 fish in it. There was quite a bit of algae, so I couldn't exactly see the fish. The tank needed draining anyways, so I watered all my fruit trees and dirt-resident garden plants. As the water lowered, I could slowly slip the net under one, lift and quickly get it into the ice bath and close the lid. (Yes, they thrash a bit, but I was kinda busy, so I tried not to listen.) Since the whole process took about 2 hours (remember...750 gallons), the fish were well dead and well chilled. They averaged 11.6" and 1.25 lbs, with the biggest one measuring 13" and 1.5 lbs. We had beer battered Baja fish tacos this past Tuesday and they tasted great! I don't think there was any more 'stress' than fishing in a lake using a hook...seems there'd be less stress by using the chill-factor.

Such real satisfaction in eating a fish you've raised to harvest-size, processed and prepared a meal with, knowing it wasn't fed a bunch of chemicals and 'unknowns'!

You'll do just fine, Sunny. If it helps, after you place them in the ice bath, just leave them in there with the lid closed. As long as the water is icey, they won't spoil or anything. They usually expire within 15-20 minutes. So step away for a little while and go set up the area you'll use to fillet or descale, or however you choose. I recently found a video on filleting to help get the highest yield. http://www.youtube.com/watch?v=OqFGxgJsW0U             The video also shows the ice bath process.

I filleted most of them, but got tired and just descaled the last one, cutting off all the non-edibles. I ended up with a total of 3 lbs of yield.

Good luck...

Hi Scott,

Thank you for the caution.  However, I'm not at all convinced at what the FDA is claiming.  Something smells "fishy" in what they are saying.  I will do more research before I say more.  I don't know about Aqui-s, (I will check on it)  but a pure, organic Clove Oil truly is marked GRAS (Generally Regarded As Safe) for human consumption. I'm not sure how using some in the fish water to keep fish calm, or prevent their fear or misery, would be harmful.  "Fishy." Fish and people in many countries are benefitting and suffering less because of this Clove Oil.



Scott Roberts said:

be careful with clove oil. From the missed-link earlier.

"AQUI-S is a pharmaceutical derivative that contains 50% active ingredient and is registered for use with food fish in New Zealand and Australia with a nil withdrawal period. However, neither anesthetic is approved for use with fish in North America. "

 

and from the FDA (LINKAGE)

Although clove oil and some of its components are generally recognized as safe (GRAS) for use in dental cement or as food additives, neither clove oil nor any of its components are GRAS for use as an anesthetic for fish. 

Because some clove oil products may contain or include either methyleugenol or isoeugenol, or both, CVM is concerned that the use of clove oil or its components in fish may adversely affect human food safety and animal food safety. This concern especially applies to the use of Clove Oil or any of its components in fish intended for use in human or animal food 

Hey - would a fish-guillotine be humane enough? Just watch your fingers!

Bob, I've got an email out to the company that makes Aqui-S. They were very helpful in their first response.  I think I'm going to encourage them to join our discussion and answer questions.  I have a background in Essential Oils, and am hopeful that this may be the answer I'm looking for.  I'm also researching the constituents the FDA was picking on, and finding very questionable claims and even doses given that were 10,000 (!!) times what should have been given, to evoke a response.  I think I'd have problems with any element given in such a high dose.  I don't understand why.  Fishy.

Also, thank you for the good illustration for the death blow.  I would be more likely to try that on a fish first anesthetized by Aqui-S.  Apparently they use this product before fish surgery and the like, too. 

Bob Campbell said:

The blow should be on the top of the head,  Spinal reflexes may continue for awhile afterwards but this does not mean that there is brain activity

I hate doing this, so I do all that I can to be gentle, but committed to making the first strike count with a strong blow that breaks the scull.  By holding the fish with a towel or the net you can get a good clean strike the first time, but I will admit I club them a few times rather than just once because I want no doubt in my mind. 

The video "Killing a Big Fish"  does not appear to be done well.  I think some people loose compassion or never had it in the first place.  Some of those videos are cruel and inexcusable. 

If your first kill does not go as well as you had hoped just remember you did your best, and think about how you can improve.  You don't need to have a lot of muscle, just strength to do what you must as well as you can.

I mainly wanted to let those who use ice water and CO2 know that scientific research shows these methods to be deceiving.  They are not compassionate methods of dispersing a fish.

It's good that people are trying to make these changes.  I was watching a cooking show and the chef was disqualified after she placed a live lobster into a boiling pot of water.  The judges told her she should have first spiked the lobster in the brain.

@Sunny - I looked at the product you linked us to.   It sounds good.  Are there any industry endorsements?



Sunny Oettel said:

Wow, Bob, it is admirable that you would take the time to write an article for the sake of those creatures that have no voice.  I'm a little scared if I as a girl would be strong enough to kill them with the first blow? Is there anywhere that explains where on the head is most effective?

Thank you, Pam, for the recipe, mmm!  Now to get the courage....

Pam DeLong said:

First off, different types of clove essential oils extracted at different times of the plants' life span produce different amounts and kinds of constituents, so I don't even know if Aqui-S even contains one or both of those constituents.  Second, I'm not sure that they would present a health risk, even if the oil did contain them.  I just looked up Methyleugenol, and found a scientific report that starts out "Methyl eugenol is a naturally occurring material found in a variety of food sources, including spices, oils, and nutritionally important foods such as bananas and oranges...and ends with ...Furthermore, there are no known health effects in humans that result from typical dietary exposure to methyl eugenol."  I'm going to invite the makers of Aqui-S to  answer our questions--they would know better than I do.

Sunny Oettel said:

Hi Scott,

Thank you for the caution.  However, I'm not at all convinced at what the FDA is claiming.  Something smells "fishy" in what they are saying.  I will do more research before I say more.  I don't know about Aqui-s, (I will check on it)  but a pure, organic Clove Oil truly is marked GRAS (Generally Regarded As Safe) for human consumption. I'm not sure how using some in the fish water to keep fish calm, or prevent their fear or misery, would be harmful.  "Fishy." Fish and people in many countries are benefitting and suffering less because of this Clove Oil.



Scott Roberts said:

be careful with clove oil. From the missed-link earlier.

"AQUI-S is a pharmaceutical derivative that contains 50% active ingredient and is registered for use with food fish in New Zealand and Australia with a nil withdrawal period. However, neither anesthetic is approved for use with fish in North America. "

 

and from the FDA (LINKAGE)

Although clove oil and some of its components are generally recognized as safe (GRAS) for use in dental cement or as food additives, neither clove oil nor any of its components are GRAS for use as an anesthetic for fish. 

Because some clove oil products may contain or include either methyleugenol or isoeugenol, or both, CVM is concerned that the use of clove oil or its components in fish may adversely affect human food safety and animal food safety. This concern especially applies to the use of Clove Oil or any of its components in fish intended for use in human or animal food 

Hey - would a fish-guillotine be humane enough? Just watch your fingers!

I just found this on 

http://www.cookingissues.com/2009/09/15/fish-anesthesiologists/  

Why isn’t isoeugenol approved in the US?

Oil of clove has been used an anesthetic and as a food and perfume additive for a long-long time. It contains both eugenol and isoeugenol. Recently, the National Toxicology Program of the NIH has called eugenol (not isoeugenol) an “equivocal carcinogen” (meaning maybe a carcinogen, maybe not). The exhaustive study is here. The evidence seems rather weak. Furthermore, the same group didn’t find isoeugenol to be a carcinogen (see here). Also, the amount of isoeugenol we would consume from eating a knocked out fish is low (see here). Nevertheless, the FDA has been hesitant to approve it. Their current opinion is here.

As a final note, here is a paper on the ins and outs of anesthetizing fish



Sunny Oettel said:

Hi Scott,

Thank you for the caution.  However, I'm not at all convinced at what the FDA is claiming.  Something smells "fishy" in what they are saying.  I will do more research before I say more.  I don't know about Aqui-s, (I will check on it)  but a pure, organic Clove Oil truly is marked GRAS (Generally Regarded As Safe) for human consumption. I'm not sure how using some in the fish water to keep fish calm, or prevent their fear or misery, would be harmful.  "Fishy." Fish and people in many countries are benefitting and suffering less because of this Clove Oil.



Scott Roberts said:

be careful with clove oil. From the missed-link earlier.

"AQUI-S is a pharmaceutical derivative that contains 50% active ingredient and is registered for use with food fish in New Zealand and Australia with a nil withdrawal period. However, neither anesthetic is approved for use with fish in North America. "

 

and from the FDA (LINKAGE)

Although clove oil and some of its components are generally recognized as safe (GRAS) for use in dental cement or as food additives, neither clove oil nor any of its components are GRAS for use as an anesthetic for fish. 

Because some clove oil products may contain or include either methyleugenol or isoeugenol, or both, CVM is concerned that the use of clove oil or its components in fish may adversely affect human food safety and animal food safety. This concern especially applies to the use of Clove Oil or any of its components in fish intended for use in human or animal food 

Hey - would a fish-guillotine be humane enough? Just watch your fingers!

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