The medium-chain fatty acids used to produce MCT oil (stands for middle chain triglyceride) come from the kernel oils of tropical palms: the seeds (kernels) of the coconut palm Cocos nucifera and/or the oil palm Elaeis guineensis.
The coconut palm reaches a height of about 20 to 25 meters and bears a shock of palm-typical pinnate leaves up to 7 meters long. The "coconut" is the seed (kernel) of the coconut drupe. Its white storage tissue (copra) that surrounds the coconut water inside has a high oil content.
Oil palms grow to a maximum height of 30 meters. Only as it grows in length does it develop a strong trunk, on which the leaf bases of detached older leaflets remain. Along strong inflorescence axes, numerous orange-red (containing carotenoids) drupes ripen with up to 50 percent palm oil in the mesocarp (outer pulp) and - not to be confused: palm kernel oil in the seed in similar proportions.
Coconut palms originate from the tropics of South to Southeast Asia. The main suppliers of the more than 62 million metric tons of global crop in 2019 were Indonesia (17 million metric tons), the Philippines and India (nearly 15 million metric tons each). At 6- to 7-years-old, palms begin producing fruit throughout the year. Knives are used to harvest individual fruits that are still immature.
The origin of the oil palm is in tropical West Africa. Well over half of the world's 411 million tons of oil palm fruit in 2019 came from Indonesia, which has overtaken Malaysia as the former world leader. Thailand is third, with Nigeria number four. Here, too, harvesting of the fruit stalks, which weigh up to 50 kilograms, is done year-round and by hand.
Neutral oil contains exclusively triglycerides of the saturated medium-chain fatty acids capric (6:0), caprylic (C8:0), capric (C10:0) and lauric (C12:0) acid. After hydrolysis of the starting oils, they are fractionated and esterified with glycerol to MCT. Different product qualities differ in the respective fatty acid proportions, which determine the physicochemical properties. In the case of high quality, caprylic and/or capric acid predominate. Compared to natural fats and oils with predominantly long-chain fatty acids, MCTs are more water-soluble, tasteless and odorless, very thin-bodied, have a lower energy content and lower smoke point.
Medium-chain triglycerides can be metabolized very easily and quickly by the body. Neither bile acids nor pancreatic lipase are necessary for digestion. Gastric lipase hydrolyzes part of it to fatty acids, the rest takes the direct route from the blood to the liver unchanged. There, MCTs are preferentially oxidized, since transport via carnitine is also omitted. Storage in fatty tissue therefore hardly takes place and ketone bodies are increasingly formed.
Medicine and dietetics use MCT oil for various disorders and diseases with fat malabsorption as well as for the ketogenic diet, for example for epilepsy patients. For weight control in obesity with neutral oil, the data situation is not yet evident due to the lack of long-term studies.
As an edible oil, neutral oil is at best suitable for cold application and in margarines. MCT oils are also considered as a dietary supplement in sports and fitness, which quickly provides energy.
Cosmetics such as oils, lotions, creams and ointments benefit from the stability, water solubility and low viscosity of MCTs. They are very well tolerated by the skin, are refatting, non-comedogenic and serve as carriers for fat-soluble active ingredients or fragrances. In pharmacotechnical terms, MCTs are interesting for tablets or coated tablets as film-forming, release and hydrophobic agents.
MCT oils (neutral oil) are considered vegetable oils, but do not occur naturally in pure form. Coconut and palm kernel oil contain 55 to 60 percent, and butter is another source of medium-chain fatty acids.