Synonyms / Languages:
Walnussöl, walnut oil, L'huile de noix, El aceite de nueces, Olio di noci, Масло из грецких орехов, ulje oraha, walnootolie, Valnød olie, Καρυδιά πετρέλαιο, dióolaj, olej z orzechów włoskich
Walnut oil is a high-quality cooking oil from ripe, partly roasted seeds of walnuts (juglans). It is from pale greenish to straw yellow color, relatively thin, has an intense, nutty flavor and is characterized by a particularly high content of triglycerides of unsaturated fatty acids. Its shelf life is even cooled only for a limited time.
The highest quality walnut oil is obtained by cold pressing with subsequent filtration. After the nuts are peeled and crushed, the oil is slowly pressed out of the nuts under pressure. In the case of multiple filtration, undesired impurities and suspended particles are separated. By this gentle process at below 40 °C, the valuable ingredients remain in the oil. The oil obtained by hot pressing or by extraction with an organic solvent is inferior to the cold-pressed oil from a nutritional physiological viewpoint. After the solvent has been removed by re-heating, the oil is refined. The refining is necessary, since during the extraction large amounts of bittering substances are added to the oil. By heating, the oil is reduced in volume and taste and thus can be used. During hot pressing the oil is obtained by a very high heat supply. The subsequent refining removes unwanted substances from the oil. The final product is a taste- and odor-neutral, relatively long-lasting oil. Because of the high heat, a lot of nutrients are lost.