Cashew nuts are kidney-shaped seeds with a delicate flavour and a slightly spongy, firm texture. The apple is a pseudofruit. The edible portion is the kernal (cashew nut). The cashew apple is used as a fresh fruit or made into juice, jams, chutneys or jellies in some countries. The thin skin, and fast decomposition of the apple, makes it difficult to transport.
Cashew nuts are actually seeds that adhere to the bottom of the cashew apple, the fruit of the cashew tree. The seed we know as the kidney-shaped cashew “nut” is delicate in flavor and firm, but slightly spongy, in texture.
You have noticed that cashews in the shell are not available in stores. This is because these nuts are always sold pre-shelled since the interior of their shells contains a caustic resin, known as cashew balm, which must be carefully removed before they are fit for consumption. This caustic resin is actually used in industry to make varnishes and insecticides.
Cashews, known scientifically as Anacardium occidentale, belong to the same family as the mango and pistachio nut.
Cashew nut contains Heart-Protective Monounsaturated Fats. Not only do cashews have a lower fat content than most other nuts, approximately 75% of their fat is unsaturated fatty acids, plus about 75% of this unsaturated fatty acid content is oleic acid, the same heart-healthy monounsaturated fat found in olive oil. Studies show that oleic acid promotes good cardiovascular health, even in individuals with diabetes. Studies of diabetic patients show that monounsaturated fat, when added to a low-fat diet, can help to reduce high triglyceride levels. Triglycerides are a form in which fats are carried in the blood, and high triglyceride levels are associated with an increased risk for heart disease, so ensuring you have some monounsaturated fats in your diet by enjoying cashews is a good idea, especially for persons with diabetes.
The cashew tree grows in the tropics and subtropics requiring high humidity and fertile soil. Related to the mango and pistachio, the cashew can grow to a height of 15 metres and may bear fruit in the second year, be productive in the fourth year, and reach maximum yields in around ten years.
The outer shell is green and leathery and turns an orange red when mature. The inner shell is hard, similar to other nut shells, and contains the edible kernal. The oil enclosed in the nut’s shell (cashew nut shell liquid or CNSL [anacardic acid]) is toxic and can burn the skin. It is used in producing plastics and as a lubricant and insecticide.
Cashew nut could be found widely in tropical countries such as India, Vietnam, Cambodia, Thailand, Indonesia, Malaysia, Brazil, Mozambique, Tanzania, Mali and Nigeria and some part of Australia.