Sunflower oil for cooking is low in saturated fat but contains high levels of linoleic acid, which is an omega-six polyunsaturated fatty acid. Most people today get more than enough omega-sixes in their diet but need to increase the amount of omega-threes, which are found in flaxseed, walnuts, and canola oil. Sunflower oil has been used for three to four centuries in North America and was brought back to Europe by Spanish explorers. Along with Argentina and Ukraine, Russia is one of the most important producers.
From Wikipedia: “Sunflower oil is the non-volatile oil compressed from the seeds of sunflower (Helianthus annuus). Sunflower oil is commonly used in food as a frying oil, and in cosmetic formulations as an emollient. ...
Sunflower oil is a monounsaturated (MUFA)/polyunsaturated (PUFA) mixture of mostly oleic acid (omega-9)-linoleic acid (omega-6) group of oils. The oil content of the seed ranges from 22% to 36% (average, 28%): the kernel contains 45–55% oil. The expressed oil is of light amber color with a mild and pleasant flavor; refined oil is pale yellow. Refining losses are low and the oil has good keeping qualities with light tendency for flavor reversion. The oil contains appreciable quantities of vitamin E, sterols, squalene, and other aliphatic hydrocarbons.”
“Refined sunflower oil is used for low-to-extremely-high-temperature cooking. As a frying oil, it behaves as a typical vegetable triglyceride. Unrefined sunflower oil is a traditional salad dressing in Eastern European cuisines. Sunflower oil is also an ingredient in sunflower butter. It may also help food stay fresher and healthier for longer periods of time.
Methods for cooking snack foods, such as potato chips or French fries, may use sunflower oil.”
“Several varieties of sunflower oilseeds have been developed by standard plant breeding methods, mainly to vary the amount of oleic acid and linoleic acid which, respectively, are the predominant monounsaturated and polyunsaturated fats in sunflower oil.
While the original oilseed was high in linoleic acid, a polyunsaturated ω-6 fatty acid, a premium high oleic acid strain was developed in the late twentieth century. Early in the 21st century, a mid-oleic strain marketed as Nu-Sun was introduced as an improved frying oil that would have a low level of saturated fat, but would not require hydrogenation. These three major strains have been purposely bred to differ in their levels of monounsaturated and polyunsaturated fats, saturated fat and tocopherols. All seed hybrids and the resulting different sunflower oils are mostly devoid of essential nutrients, with the notable exception of vitamin E which is high in content in all varieties.”
Preparation and storage:
“Because sunflower oil is primarily composed of healthier-but-less-stable polyunsaturated and monounsaturated fatty acids, it can be particularly susceptible to degradation by heat, air, and light, which trigger and accelerate oxidation. Keeping sunflower oil at low temperatures during manufacture and storage can help minimize rancidity and nutrient loss—as can storage in bottles that are made of either darkly-colored glass, or, plastic that has been treated with an ultraviolet light protectant.”
Methods of extraction:
“Sunflower oil can be extracted using chemical solvents (e.g., hexane), or expeller pressing (i.e., squeezed directly from sunflower seeds by crushing them). "Cold-pressing"/expeller-pressing sunflower seed oil under low-temperature conditions is a preferred method, for those seeking an extraction process that doesn't involve chemical solvents, as well as for people following a raw foods diet.”
Refined versus unrefined:
“Refining sunflower oil through solvent extraction, de-gumming, neutralization, and bleaching can make it more stable and suitable for high-temperature cooking; but, will also remove some of the oil's nutrients; flavor; color (resulting in a pale-yellow); free fatty acids; phospholipids; polyphenols; and, phytosterols. Unrefined sunflower oil is less heat-stable (and therefore well-suited to dishes that are either raw or cooked at low temperatures); but, will retain more of its original nutrient content, flavor, and color (light-amber).”
“Extraction of sunflower oil leaves behind the crushed seeds, typically referred to as seed meal, which is rich in protein and dietary fiber and used as an animal feed, fertilizer or fuel. ...
Sunflower oil can be used to run diesel engines when mixed with diesel in the tank. Due to the high levels of unsaturated fats, there is higher viscosity in cold temperatures.”
“In recent years, there has been an increase in demand for sunflower crops such as sunflower oil. Measures such as the development of hybrid sunflowers to increase oil production have been introduced to meet this demand.”