Olej

Olej is a broad term in Polish for liquids rich in triglycerides that are used as sources of energy and in various technical applications. It covers edible oils derived from plants or animals, as well as non-edible oils such as lubricants and fuels. Most edible oils are produced by pressing seeds, fruits, or nuts and may be followed by solvent extraction to recover additional oil. Refining steps such as degumming, neutralization, bleaching, and deodorization are commonly applied to remove impurities, improve flavour, stability, and storage life.

Common edible oils include olive oil, sunflower oil, canola (rapeseed) oil, soybean oil, palm oil, and coconut oil. They differ in fatty-acid composition, including saturated fats, monounsaturated fats, and polyunsaturated fats, which influences taste, cooking properties, and health effects. Smoke point varies by type and refinement, affecting suitability for frying or high-heat cooking.

Nutritionally, oils are energy-dense foods providing about 9 kilocalories per gram and essential fatty acids, fat-soluble vitamins, and other compounds. Regular consumption should be balanced with other fats, taking into account saturated fat content and overall dietary patterns.

Uses and storage: In the kitchen, oils are used for frying, sautéing, dressings, and flavouring. They are also employed in cosmetics, pharmaceuticals, and industry. Oil quality degrades through oxidation, so oils are stored in cool, dark places, in sealed containers; oxidation and rancidity are signs of spoilage. Shelf life depends on oil type, processing, and storage conditions.