Potential Dangers of Pomace Olive Oil: Cheaper is Not Always Better
During my mother’s most recent search for olive oil at a local grocer, she selected a cheaper option which she had never purchased before. This oil was shelved with dozens of other well-known, respectable olive oils, packaged in an attractive glass bottle, adorned with a hearty olive tree and wavering Italian flag, and beneath it all, the mysterious label “pomace olive oil.”
Unsure of what this meant exactly, but pleased with the price and the promises of various hype words and advertising jargon, my mother made the buy. Later she realized she had purchased a lesser grade of olive oil which lacked the expected flavor of her usual EVOO.
The smell, taste and texture of the imposter was nothing like extra virgin, and upon further inspection and a quick consultation of a number of sources, we found out that my mother, as well as a great number of other consumers complaining vehemently over the internet, had unwittingly purchased a bastardized product that wasn’t even olive oil — but something called “olive pomace oil.”
Further research revealed that the Spanish government, notorious for its strict regulation of olive oil products, had temporarily banned the sale of this grade of olive oil in July, 2001.
I had never heard of pomace olive oil at all and after a quick survey of friends and family, I found out that I was not alone. I was astounded by my own ignorance of this product and that of the general public, especially considering the potential dangers of consuming pomace oil from unregulated producers. So, just what is pomace olive oil, exactly?
While extra virgin olive oil is often denoted as being “first cold-press,” what is termed “pomace oil” cannot even qualify as being “second press.” Once the typical, mechanized extraction of olive oil from the olive fruit is complete, some 5 to 8 percent of the oil still remains in the leftover olive pulp or “pomace.” Although the pomace oil that is extracted is still technically oil that comes from olives, this is done via the use of chemical solvents, and therefore should never be termed, directly or indirectly, as “olive oil.”
The International Olive Council (IOC), the intergovernmental organization responsible for outlining quality standards and monitoring olive oil authenticity, clearly defines olive oil as, “oil obtained solely from the fruit of the olive tree, to the exclusion of oils obtained using solvents or re-esterification processes.” The amount of oil contained in the leftover pomace, which consists of the solid remains of the olive including skins, pulp, seeds, and stems, is so minimal that it cannot be extracted by pressing, but only through the combined use of chemical solvents (like Hexane) and extremely high heat.
See more: International Standard for Olive Oil (IOC)
This very process, the same high heat technique used in producing canola, sunflower, and other vegetable oils, is why unregulated olive pomace oil sometimes contain harmful components known as polycyclic aromatic hydrocarbons (PAHs) like benzopyrene, which research has shown to be highly carcinogenic and mutagenic. Benzopyrenes result from the incomplete combustion of the fats present in the olives. When fats are exposed to levels of high heat, like in the pomace oil extraction processes where there is no complete combustion and no smoke is produced, benzopyrenes are likely to be produced as a result.
The process to extract olive pomace oil is as follows: a chemical solvent is first administered to the olive pomace which has the ability to dissolve the fats but not the rest of the solid pomace. This application extracts the oil and then afterward, in a refining process, the product is heated so the solvent evaporates completely and cleanly without leaving any sort of harmful residue — so long that this heating method does not exceed 90 degrees Celsius (194 degrees Farenheit). Using this system, the final product is not likely to contain polycyclic aromatic hydrocarbons (PAHs) like benzopyrene.
The risk of benzopyrene contamination occurs when the heating method used to evaporate the solvent exceeds 300 degrees Celsius (572 degrees Farenheit). In these instances, the fat is liquefied into fluid and then drips out of the olive pomace, but the problem is that the insanely high heat results in the partial combustion of the oil with the rest of the physical pomace. This can cause the rapid accumulation of benzopyrenes in the final product.
In instances of heat applications above 300 degrees Celsius, the resulting oil comes with a definite health risk for consumers which depends entirely on the aggressiveness of the heat treatment as well as the amount and frequency of the pomace oil consumed. Because the degree of contamination depends on the type of treatment used, it is necessary for health authorities to clarify what kind of treatment has been applied to produce particular pomace oils and to establish a permissible limit of the amount of benzopyrenes present.
Benzopyrenes, being themselves highly reactive fats, can dissolve easily into cellular membranes and thereby enter a cell’s interior. This resulting action has been shown to cause either intracellular oxidation–the aging and death of cells–or an intoxication which results in the mutagenesis of the genetic material in the cell’ s nucleus. In some instances, this of course spreads as an uncontrolled multiplication of damaged cells which can result in a cancerous tumor.
Concerned about the levels of PAHs like benzoyprene in pomace oil, the Spanish government introduced a temporary ban on pomace oil in July, 2001 and halted all exports of pomace oil until tests were conducted and limits of the allowable amounts of PAH’s present in the oil were made concrete.
Other countries followed suit: the New Zealand Health and Food Safety authority recalled olive pomace oil from several manufacturers and the German ministry acted similarly issuing this warning: “As a preventative health protection measure, the ministry for consumer affairs, nutrition and agriculture has appealed to the German states and industry to review the remains of the 170 tons of Spanish olive-pomace oil and products containing this oil.”
It later became apparent that other affected batches were produced in Greece (Bevelini Olive Pomace Oil) and others from Italy (Dentamano Olio di Sansa de Oliva). In the Bevelini product, for example, a batch was reported to contain 100 parts per billion of benzopyrene — over 50 times the limit advised by the International Olive Council. And although human exposure to PAHs is something of the quotidian — as they are also created with the combustion of fossil fuels, burning trash, agricultural fires, industrial processes, tobacco smoke and vehicle exhaust emissions — our exposure to PAHs should be as limited as much as possible, especially when ingesting food.
As a result, specific standards have been set in various regions of the world limiting the allowable amount of benzopyrenes in pomace olive oil. As mentioned previously, within the European Union and in member states of the IOC, the limit is 2 parts per billion or 2 micrograms per kilogram as decided in Resolution RES-1/93-IV/05 Madrid in November of 2005.
With that said, however, in other olive oil producing countries which are non-IOC members (India, emerging Middle Eastern producers, several Latin American states, and even the United States where retail grades have no legal meaning) such stringent standards are not enforced and therefore the purchase of pomace oil products from these regions is not advisable.
Even with the regulation of the amount of PAH’s in pomace oil, culinary aficionados and olive oil connoisseurs worldwide are still highly resistant to the idea of using olive pomace oil as a worthy cooking agent. From a sensory standpoint, it lacks the flavor, delicacy, and bountiful healthful properties of extra virgin olive oil. If used in the kitchen at all, pomace oil is mostly used in industrial settings or in restaurants as a deep frying agent because of its high smoke point (240 degrees Celsius).
Unfortunately, sometimes we buy olive pomace oil unintentionally, thanks to unethical producers who have been known to commit fraud by mislabeling cans or bottles of olive pomace oil.
See more: Trade Group Sues Olive Oil Producer for Deceptive Labeling
But it’s also important to note that the process by which pomace oil is extracted is no different to the process used to extract other conventional cooking oils such as corn, soy, sunflower, safflower, canola, or cottonseed and in comparison to these oils, pomace oil still retains olive oil’s basic lipid profile and therefore boasts high levels of oleanolic acid which has been proven to relieve states of hypertension and high blood pressure.
If you do happen to buy a bottle of pomace oil accidentally and are still resistant to the idea of using it as a cooking agent, you need not throw it away as there are a number of uses for it. In fact, because it is a monounsaturated fat, it is a better choice for cooking than other seed oils like canola, sunflower or peanut. Unwanted pomace oil can also be used to create soap or for lubricating grill racks or pans. But with all of the available olive oils on the market today, it’s in your best interest from both a health and culinary standpoint to stick to extra virgin. Believe me, your taste buds will thank you.
- Trade Standard Applying to Olive Oils and Olive-Pomace Oils” (PDF) International Olive Council, November 2009
- Los riesgos del aceite de orujo” José Juan Rodríguez
- Germany warns about Spanish olive-pomace oil” July 10, 2001
- Olive-Pomace Oil: Your questions answered” August 14, 2001
- Detection of Polycyclic Aromatic Hydrocarbons in Edible Olive Oils and Olive Pomace Oils (PDF) International Olive Council