Most fat in our bodies and in the food we eat is in the form of triglycerides. Triglycerides make up by far the largest proportion of dietary lipids consumed by humans. When triglycerides are broken down free fatty acids are formed. This can occur during the process of rancidity.
There Are Two Main Forms Of Rancidity:
- Hydrolytic Rancidity
- Oxidative Rancidity
Hydrolytic rancidity involves the breakdown of triglycerides into their component fatty acids and glycerol. These liberated fatty acids can create a rancid odor and off-flavor when released into the air. Deep-fat frying commonly results in hydrolytic rancidity. The EU insists on measuring free fatty acids (measured as: “% free fatty acids” or “acid value”) because their levels indicate the quality and freshness of an oil.
Elevated Free Fatty Acids Are A Problem. Why?
Because free fatty acids are more “prone” to oxidation than fatty acids in their triglyceride state. The more free fatty acids floating around in a fish oil the greater likelihood for oxidative rancidity. Free fatty acids can therefore undergo oxidation to give rise to what is known as free fatty acid hydroperoxides.
The Problem With Hydroperoxides
- Research suggests that ingested omega-3 hydroperoxides may lead to cell membrane peroxidation, cell damage, and oxidative stress. Oxidative stress activates pathways that increase the production of pro-inflammatory chemicals resulting in inflammation. Chronic low grade inflammation has been associated with degenerative disease.
- As fish oils reach more advanced stages of rancidity, hydroperoxides degrade to form potentially harmful secondary oxidation products including toxic aldehydes (such as malondialdehyde). Secondary oxidation products can be detected by various tests including the “TBARS assay”. Always ask your manufacturer for the test results. And most importantly, make sure the analytical test results originate from a very respected institution. Fish oils in an advanced state of rancidity should be completely avoided.
Controlling The Rancid Factors
Factors accelerating the formation of hydroperoxide in fish oils include oxygen & light, high temperature, contact with brine (salt solution), moisture, too little or too many antioxidants, and certain transition metals such as iron. If these factors are not controlled during the harvesting, extraction and bottling of cod liver oil it is almost certain the oil will go rancid. On the flip side controlling these factors keeps the oil fresh preventing both hydrolytic and oxidative rancidity. In the production of Extra-Virgin Cod Liver Oil, Rosita has gone to great lengths and expense to address every one of these rancid factors.
To decrease the oil’s exposure to oxygen freshly caught wild Atlantic cod are quickly harvested, extracted, bottled and capped free of oxygen. The temperatures during the entire process, even in the bottling facility are kept low and the consumer is also asked to refrigerate the oil during use to extend freshness. The freshly harvested cod livers are never left to sit in brine water (which accelerates oxidative rancidity) or mixed with blood and gall to reduce moisture content as much as possible. The lights at the bottling facility are dimmed, the oil poured into amber bottles and immediately boxed in cases to reduce the oil’s exposure to light. Ceramic knives (their Norse ancestors used knives made of stone or bone) are used to harvest the livers and the oil never touches metal during the entire process. Rosita spent more than two years researching & testing just the right amount of 100% natural antioxidants (plant Rosemary and vitamin E from organic seeds) to add to EVCLO for lasting freshness. A great deal of time and expense went into controlling all of these rancid factors. The end result is the freshest and rawest wild-caught cod liver oil available, harvested & produced by real Norwegian fishermen using the techniques of their ancient ancestors who were the true originators and masters of fish liver oil production! And an oil that can be enjoyed by young and old alike for good health and vitality.
Some Companies Produce Fish Oils With Elevated Fatty Acid Levels
For some very peculiar reason there are companies producing fish oils with high levels of free fatty acids. These same companies also offer concentrate oils and fish oils with custom EPA/DHA ratios. Not very natural. These companies are not using rancidity to release the fatty acids from the triglyceride molecule. Instead, their fish oils undergo deliberate treatment to release the fatty acids from the triglyceride molecule. They also refine their oils to prevent oxidation of these free fatty acids, including the use of molecular distillation. Are such fats better? Absolutely not. And they are definitely not natural.
The Norse people & Vikings commonly consumed raw fish livers while out at sea to help maintain strength and resistance to cold. These livers were rich in Extra-Virgin Oil in their natural triglyceride form. However, take the liver out of the fish and leave it to decay. Guess what happens? The free fatty acid levels begin to rise and so does oxidative rancidity too.