How to Make Fish Oil

Co-authored by wikiHow Staff

Last Updated: January 31, 2023 References Tested

You can’t extract fish oil that is safe for human consumption at home, so don't take fish oil as a dietary supplement unless you’ve purchased it from a reputable manufacturer. However, you can make fish oil that you can use to attract fish or mask your smell when you’re hunting. Take an oily fish like salmon or sardines, gut it, and cut it into small chunks. Place the chunks into a container, cover it, and let it sit for 2 weeks in the sun. Then, strain the liquid into jars and allow the oil to separate and float to the top. Scoop out the fish oil and you’re all set!

Part 1

Part 1 of 2:

Gutting the Fish

1
Choose an oily fish like sardines to make oil with. Sardines have some of the highest concentrations of omega-3 fatty acids and vitamins. They’re also full of fish oil, which makes extracting the oil easier.^{[1]
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- Other oily fish include herring, mackerel, trout, and salmon.
- You can use almost any type of fish to make fish oil, but fatty and oily fish will allow you to extract more.
2
Cut off the head and tail from the fish with a filet knife. Place the edge of the filet knife just behind the gills of the fish. Cut all the way through the fish to remove the head. Then, place the knife against the tail of the fish, just below where the fin starts. Cut through the body of the fish to remove the tail.^{[2]
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- Throw away the heads and tails. They will not contribute to the oil that you’re trying to extract. The organs in the head will putrefy and could affect the quality of the fish oil.
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3
Insert the tip of the knife into the vent of the fish. The vent is the lowest portion of the underside of the fish. Tilt the fish at a 45-degree angle with the head facing away from you and look for a small opening near the tail section on the underside. Insert the tip of the filet knife about 1 inch (2.5 cm) into the vent of the fish.^{[3]
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- The vent is also the anus of the fish.
Warning: Do not hold the fish in your hand or you could cut yourself. Place it on a flat surface such as a table so it’s stable.
4
Slice down towards the neck of the fish. Keeping the tip of the blade inserted and hold the fish firmly. Slide the blade down toward the neck end of the fish. The belly will cut open and you’ll be able to see the organs inside of the fish.^{[4]
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- Be careful not to cut too deeply or you could burst an organ, which is messy and smelly.
5
Pull out the guts and entrails from inside of the fish. Use your fingers to grab the intestines, stomach, and other guts inside of the fish. Pull them out of the fish so there’s nothing left but a hollow cavity.^{[5]
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- Throw the organs away, or use them as bait to catch other fish.
- Wear rubber gloves to avoid getting fish guts on your hands.
6
Cut the fish into 1 inch (2.5 cm) chunks. Cutting the fish into smaller pieces will allow it to break down faster and release the oils inside of them. Use a filet knife or a butcher’s knife to cut or chop up the fish into small chunks.^{[6]
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- Cut the fish on a flat surface like a table or cutting board.
- Do not hold the fish when you cut them so you don’t risk injuring yourself with the knife.
7
Place the chunks of fish into a plastic container with a lid. Use a large bucket or plastic container that has a lid that closes securely over it. Put all of the chunks of fish that you cut up into the container and close the lid.^{[7]
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- A secure container will keep out other animals that may smell and be attracted to the fish.

Part 2

Part 2 of 2:

Separating the Fish Oil

1
Put the bucket in the sun for 2 weeks. The fish need time to break down and release the oil trapped inside of them. Keep the lid closed and set the container outside in a sunny area to help speed up the process.^{[8]
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- Don’t place the container in a place that other animals can easily access it.
Tip: The container of fish will start to smell as it breaks down, so place it away from your home or in an area where people won’t smell it.
2
Strain the liquid in the bucket through cheesecloth. The fish in the container will start to liquefy as they break down and release their oils. Pour the liquid through cheesecloth and into another clean container to strain any solid particles from it.^{[9]
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- Use another bucket or plastic container to catch the strained liquid.
3
Pour the strained liquid into jars and cover it. Separate the strained liquid into jars or smaller containers so it can settle. Seal the liquid in the jar with a lid or covering.^{[10]
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- Clear jars or containers will allow you to see if there are any additional particles you need to strain out.
- Use glass or plastic jars or jugs to collect the fish oil.
Tip: If you don’t have a lid, wrap the opening with plastic wrap to keep it covered.
4
Allow the jar to sit for 1 day so the fish oil separates. The liquid inside of the jars will start to settle over time and separate. The water will sink to the bottom of the jars and the fish oil will float to the top and collect. Allow enough time for the oil to separate entirely.^{[11]
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- Do not touch or disturb the jars while the liquid separates.
- If the liquid hasn’t separated after a day, allow it to sit for another 12 hours and check it again.
5
Scoop out the separated oil into a clean container. After the fish oil has separated, it will appear as a large glob on top of the water in the jars. Carefully dip a spoon or ladle into the jar and scoop the fish oil out into another container. You’ll then have pure fish oil.^{[12]
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- The fish oil will keep for up to a month in a sealed container.
6
Use the oil to bait fishing lures or cover your scent. You can spread the oil on the fishing line, hook, and bait to attract more fish when you cast them into the water. Alternatively, smear the oil on your hunting gear to mask your scent so you don’t scare off any game when you’re hunting.^{[13]
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- A little fish oil goes a long way! Rub a small amount on your hook or apply about ¹⁄₂ teaspoon (2.5 mL) to your hunting attire to cover your scent.