Pressure Bleeding

Discussion related to commercial salmon trolling, boats, gear, fishing techniques, electronics, marketing, etc.
ZaneSOS
Member
Posts: 5
Joined: Fri Dec 20, 2013 2:05 am
Spammer?: No

Bleeding the tail

Post by ZaneSOS »

I've been away for awhile, learning this process. You may recall that I gillnet and emphasize PB Sockeye, that I am working to establish a distinct PB market that pays a premium for proper PB fish, and that I am not exclusive to gillnet-caught fish. It is all working out. I am slowly creating a premium market - keeping supply level so the market does not flood before demand grows. The exclusivity of PB fish secures our premium price, So..

So, I learned a trick or two this summer that I am not sure everyone else knows. As a fisherman, I have the reflex to hold onto any potential secret advantage I can. As a man in the business of promoting the quality and benefits of Pressure Bleeding fish, helping fishermen to self-market, and promote overall fishing ethics and sustainability, it is essential to share information that helps the quality of the process. The second guy wins today.

The first development I found was tail bleeding. Some of my friends working hard to do the best PB they can have mentioned that they have residual blood in the tail of the fish along the spine. Winston, of Taku River Reds, showed me a little trick that helps get the majority of that tail blood out:
Take this step after initial kidney removal step, but before any rough scraping of the spine.
Using a 2 to 2.5 inch veterinary syringe (for salmon, longer for halibut) with the tip dulled or removed, and a low flow rate, bleed the tail.
Insert the tip of the syringe parallel to the spine at the tail end. "What?"
If one looks down the length of a dressed (head off) fish from the head end, there are visible holes in the rear vertebrae that almost form a tunnel through the spine toward the back of the fish. These are the same last vertebrae that are usually cut to get kidney remnants out.
Insert the syringe into this vertebral tunnel. As you insert you will feel two points of slight resistance. When you pass through the second point, stop. You can then watch the tail blood flow out now. It is a beautiful sight. Then I use a toothbrush to get all of the kidney out of the rear spine area. Upon fillet, a few of the fish may have some trace residual blood along the spine that had begun to coagulate. Rinse that off, it is not in the meat. The fish will pass the test below.
The real test I found to check PB quality is when I vacuum pack the fish. Traditional fish or poorly pressure bled fish release any blood to the visible surface of vacuum bags. It looks awful next to PB fish. I have so many photos... and video. You can also compress a fish fillet from head towards tail, and blood will show if it is there. This is rough on fish though.
ZaneSOS
Member
Posts: 5
Joined: Fri Dec 20, 2013 2:05 am
Spammer?: No

Closed loop system

Post by ZaneSOS »

A friend asked me about what I do to regulate pressure in my system. I'm still working to master this, but here is what I do that seems to be working. I will try to attach a horrible drawing I made to show what I'm writing. It may do more harm than good, but I didn't get a picture that shows this part of the system well enough this year:

This year I used a Flojet 4305 pump with a pressure regulator built in. Similar pumps should work. It puts out about 5 gpm at about 40 psi. This goes into a potable water hose. (The 2015 year's system is going to use industrial components) A trick I learned in Ag to balance pressure is to create a looped system. This is easy to do, and I'll describe it using easy to find pars. All hoses are the crappy potable water hoses in this example.

The main hose from the pump gets the water to the work area in one line. Then attach a Y connector to the hose. Pick a right length second hose to make it from the Y connector to the first of these items, each item is fed by another Y connector (with a shut-off valve) in the line and separated by another short length of hose:

One hose will have a tube with a pipette. What I used was a fitting at the Y connector that shrank the diameter dawn to about 1/2". Then I used a food-grade Tygon tubing to run to the pipette section. There I used a piece of surgical tubing about 6" long over the Tygon and over the pipette (Trim the pipette to allow the 'pee stream' flow volume, and use the valve to control pressure - It will work if the rest of these steps are used). The surgical tubing absorbs most variations in pressure should they occur. Pressure and volume are controlled by each Y connector (I plan to use better y connectors - they rust out of commission in a couple days).

The second hose has the same set-up, but instead of the pipette I use a 2.5" veterinary syringe with a trimmed tip. This is the one for bleeding the tail. I use a zip tie to fasten the tubing and syringe together because when I turn on the Y connector to this one it can shoot right off the boat. It is important to adjust the Y connectors.

The third hose has a spray head on it to rise the fish and work area. I use a twist-open brass head. Sudden use of the spray head can drop pressure.

The final step, the one that balances the pressure is a return hose. This hose goes from the Y connector at the last of the three work hoses back to the first Y connector - the one from the main pump feed. This , along with the valves on the Y connectors, will equalize the pressure in the system, and allow better control of it.

Air in the lines can cause sudden bursts of high pressure to burst the tiny capillaries in the fish and leave awful looking spots. Some spots are in the tissue of the body cavity and can be carefully removed. Others are in the meat, and are there to stay.

I don't have a photo of this set up handy, so I drew a picture of what I'm describing. It might be worse than my written description. If it is at all unclear or if you would like more info or to share ideas, I am happy to help and to learn.
Attachments
IMAG0274.jpg
fveureka
Site Supporter
Site Supporter
Posts: 86
Joined: Thu May 10, 2012 1:12 pm
Spammer?: No

Re: Pressure Bleeding

Post by fveureka »

I recall on the pressure, Salty saying using a waterpressure like an old guy peeing applied to the fish spine process. I help by pushing the side vein blood out using a rubbermaid small sqeegy.
Post Reply