Palm-kernel oil is an oil which is extracted from the seeds of the oil palm, a tree native to Africa and widely cultivated in Africa and parts of Asia. The fruit which surrounds the seed can also be pressed for oil. Depending on where one lives, it may be easy or difficult to obtain pure palm-kernel oil, but products which contain this oil are often abundantly available.
This oil is not terribly healthy. It is extremely high in saturated fats, and low in essential fatty acids, making it a poor addition to the diet. Straight palm oil extracted from the fruit around the seed is actually healthier, but palm kernel oil is cheap and readily available in many regions, making it an attractive alternative to the healthier and often more expensive palm oil.
Like other oils which are very high in saturated fat, palm-kernel oil is typically solid at room temperature, and it can withstand very high heat. In parts of Africa and Asia, it is a commonly used cooking oil, and it can also be used in cosmetics. Many cosmetics manufacturers utilize this oil as an inexpensive substitute for things like coconut oil and shea butter. While it certainly gets the job done, it has less cosmetic benefits than more expensive ingredients, and some people find that it adds a somewhat greasy texture.
There are a number of ways to extract palm-kernel oil from the seeds, ranging from traditional methods which involve roasting the seeds, cracking them, and grinding them to extract the oil to more modernized methods which are designed to extract every possible drop of oil from the seeds. Several manufacturers also use a fractional distillation process to separate the oil into various components which can be sold individually, maximizing their profit.
Palm-kernel oil also comes with environmental issues. In some regions of the world, native rainforests have been cleared to make way for the cultivation of oil palms, thanks to rising demand for palm oil. In addition to being used in cooking and personal care items, this oil can also be distilled into biofuel, and because of its low expense, many biofuel manufacturers have turned to palm oil and palm-kernel oil. Clearing of rainforests for oil palm plantations has obvious environmental effects, and in some regions, the cost of palm-kernel and palm oil has climbed so high, thanks to the demand, that people cannot afford these oils for cooking.