Kosher Fat: Edible oil and by-products such as fatty acids and lecithin are a necessary ingredient in almost every food industry. As a result, the demand for kosher oil has increased globally for the ever-expanding kosher market.
In this article we will explore the various oil production processes and the requirements to be certified as kosher by the Orthodox Union. Although a seemingly innocuous item, oil production includes many phases, production agents, and equipment which need to be kosher compliant. For starters, most animal and fish-based oils cannot be certified as kosher. Common non-kosher oils include fish-oils, tallow and lard. Palmitic and stearic acid are examples of common by-products that can potentially be sourced from non-kosher oil.
Equipment: Due to increasing public health awareness to trans fats, the demand for animal-based oil has significantly dropped in recent years. Therefore there are very few edible oil refineries in the United States that refine both vegetable and animal oil. It is still common in Europe and Central and South Americas. However, there are many bottling facilities in North America that are storing and bottling non-kosher and vegetable-based oils with shared equipment.
As with all kosher products, the integrity of a kosher production line is essential. Cross-contamination with non-kosher product needs to be avoided. This is one of the many reasons that vegetable oil must be certified as kosher.
Crushing: When producing vegetable oil, the seed/bean is cleaned and dried. Foreign materials such as stones, glass, and metal, are removed by sieving and magnets. They are then disposed of outside the feed chain.
Some oilseeds, like soybeans and sunflower seed, may be de-hulled after the cleaning step. After de-hulling, the meal will have a lower crude fiber content, and hence a higher protein content. The hulls can also be used for feeding purposes, most often in pelletized form.
Seeds with high oil content, like rapeseed (canola) and sunflower seed, are usually mechanically pressed in expellers after a preheating step in (indirectly) heated conditioners. Because the expeller cake (or pressed cake) may still contain up to 18 percent oil, it is then further treated in the extractor. In some cases the expeller cake is sold for animal feed.
In the expelling process, the oil bearing material is fed into one end of a cylinder in which a power-driven worm conveyor forces the material out the other end, against resistance. The pressure squeezes the oil out. Soybeans, with relatively low oil content, are thermally treated, mechanically cracked and flaked for further extraction.
Sometimes the raw material is pressed without heating; such oils are known as cold-pressed oils. Since cold pressing does not extract all the oil, it is practiced only in the production of a few special edible oils, i.e. olive oil.
In the past, crushing was done between mill stones that later became steel rolls. That is why until today oil factories are known as oil mills and the process as oil milling or oilseed crushing, even though it is more common to extract the oil with solvents.
Solvent extraction is used to separate oil from seeds/beans where the principle is to employ a volatile liquid in which the oil is freely soluble. The common solvent used is hexane. The pre-processed seeds/beans are treated in a multistage counter-current process with solvent until the remaining oil content is reduced to the lowest possible level. The kosher certification agencies monitor the various solvents available in the ever changing world of food technology.
There is little concern that equipment used to extract the oil will be shared with non-kosher oil since non-kosher oils are not crushed. However, starting with the storage through the fillers, the tanks and lines are monitored for kosher integrity.
The OU has found that some olive oil producers have used cell wall digestive enzymes to increase the oil yield of the olives. These enzymes are potentially animal based. These enzymes have to be approved as kosher by being listed on the Schedule A, just like any other ingredient or production agent. Steam may also be used to improve yield. Although this is most often approved, in some European countries the steam is provided by a separate company nearby which may be supplying steam to a non-kosher facility, and recycling that steam with the kosher steam. This should be considered at the planning stage for kosher certification.
Degumming: Crude oils — the oil immediately following extraction — may have relatively high levels of phosphatides. Soybean oil, for example, may be degummed before refining to remove the majority of those phospholipid compounds. Phosphoric or citric acid may be used to dissociate the nonhydratable phosphatides (NHP) into phosphatidic acid (PA) and calcium or magnesium bi-phosphate salt. Both components are removed by adsorption on bleaching earth in the degumming process. The citric acid needs to be certified as kosher.
During the degumming process, the crude oil is treated with a limited amount of water in order to hydrate the phosphatides and then separate them by centrifugation. After the degumming process, the crude oil is dried to remove this added water.
Soybean oil is the most common oil to be degummed; the phospholipids are often recovered and further processed to yield a variety of lecithin products.
Distillation: The miscella — a mixture of oil and solvent — is separated by distillation into two components; oil and solvent. The solvent is recycled into the extraction process. After the oil has been manufactured into the crude state, it is either refined in the same plant or transported to a different plant for refining. All transportation of bulk oil (and any liquid) must be in kosher approved carriers.
Refining: Refining is the process by which crude oil is made ready to be used for human consumption by removing its impurities. The oil refining process involves some or all of the following steps:
1) Alkali Refining: Removes fatty acid content and other impurities. This is achieved by introducing an alkali solution into the oil while it is being heated.
2) Bleaching: Removes color producing substances and further purifies the oil. This is achieved by putting material such as bleaching clay into the oil to absorb the substances.
3) Deodorization: Removes any remaining materials in the oil that can cause spoilage or unpleasant odors. Oil is pumped into a deodorizer (a very large piece of equipment that heats the oil in a vacuum).
The kosher cleaning (kosherization) of a deodorizer is difficult and is something kashrut agencies try to avoid if possible. The preference is to use vegetable oil from plants that exclusively process vegetable oils. A deodorizer can be six stories high. There are many trays into which oil is pumped, heated, and centrifuged at temperatures as high as 700°. It is difficult to clean because after each deodorization process a film of oil adheres to the deodorizer and is not easily removed. In order to properly perform a kosher cleaning (kosherization), every inch, nook and cranny has to be cleaned until it looks brand new, which can be very labor intensive and expensive.
Off-Shore Tanks: An often overlooked issue is off shore storage. If a tanker unloads an oil hold to an off shore tank which will then be transferred to a barge or railcar, this off shore facility also requires kosher certification to verify that the tanks are not shared with any non-kosher certified oil.
Conclusion: Kosher certification monitors the mechanics of oil extraction, the agents used, and the vehicles for transporting the kosher oil. Kosher certification verifies that from the beginning of the extraction until the retail filling, all steps comply with the rigorous kosher guidelines.
The demand for kosher certified oil increases daily. The OU receives requests on a daily basis from companies around the world, including the most remote areas of the Amazon Jungles. This global reach of the OU has positioned it as the number one kosher certification agency.
It is no surprise that kosher consumers prefer oil with the OU kosher symbol!
Rabbi Akiva Tendler serves as rabbinic coordinator serving the oil, tea and beverage industries. He is a frequent contributor to BTUS. His “Documenting Intermediate Products” appeared in the Fall 2015 issue.