The Shelf Life of Pomace Oil

Extraction

• After other forms of olive oil are refined or pressed out of the olives, the leftover matter -- called pomace -- still has a significant amount of oil left, but requires chemical extraction to retrieve it. The pomace is sent to large dryers to stop enzymatic processes which could ruin the product. After drying, the pomace is ground and treated with hexane to extract the oil. The crude pomace oil is heated to distill the hexane out of it and refined to produce a useable consumer product. This additional refining makes pomace oil more stable. This stability increases the shelf-life and allows it to be used for high heat applications that would cause less refined olive oils to smoke or ignite.

Storage

• Storage of pomace oil follows the same guidelines as storing any type of oil. Keep the oil sealed in an air-tight, opaque container in a cool, dark spot. The back of the pantry is ideal, but during the summertime or in hot kitchens, the refrigerator can also be used to store pomace oil until use. Exposing the pomace oil to light or oxygen decreases its shelf life by increasing the chances it will oxidize and turn rancid.

Shelf Life

• Pomace oil has a longer shelf life than other olive oils. Properly stored, the pomace oil will remain fresh for up to one year. Check the oil periodically by smelling it. If it begins to smell rancid, throw it away. Cooking or using rancid oil in soap-making will impart the same odor on the final product. Kept in the refrigerator, pomace oil might become cloudy, but this is not a sign of deterioration, and the oil is still safe to use.

Uses

• Pomace oil is found as crude olive-pomace oil, refined olive-pomace oil or olive-pomace oil. However, only olive-pomace oil is a combination of virgin olive oil and pomace oil and useful for human consumption. The only culinary use of pomace oil is for deep-frying because it has a higher smoke point than less-refined olive oils. Pomace oil is more often used by soap-makers to reap the moisturizing benefits of olive oil in the soap at a lower cost than virgin olive oil. Using pomace oil past its shelf life could result in lower quality soaps or rancid-tasting fried foods. Discard expired pomace oil for best results.