Cashew nuts commonly known as Kaju is a delicately flavored snack. It is also used as a popular ingredient in savory dishes worldwide. It is easily available and found in the local markets all year round. The nut is actually a conical shaped seed attached to the lower portion of a fruit known as cashew apple. Cashew is a close relative of pistachio, poison ivy, poison oak and mangoes.
In it’s appearance this nut is about one inch long with a smooth, curvy pointed tip. It is soft and white with a delicate creamy surface. When roasted, the nut turns golden brown in color having a buttery texture and a fruity aroma.
Cashew is a tropical evergreen tree belonging to the Anacaradiaceae family. Its scientific name is Anacardium occidentale.
The tree is native to Brazil’s Amazon rain forest and blossoms every year from November to January. Usually growing to a height of 12 meters, the tree can grow in a wide spectrum of climatic regions.
Cashew nut was first introduced by the Portuguese explorers in the 16th century for the purpose of soil conservation and afforestation. It has now emerged as a major cash crop and is cultivated widely in Brazil, Vietnam, India and other African countries. The cashew tree grows vigorously in the first three years of cultivation.
Each tree bears numerous edible pear shaped fruits know as the cashew apple. Botanically, this fruit is a drupe having a hard outer shell grey in color. The exterior shell of this fruit has a phenolic caustic skin irritant toxin. While processing, the outer shell is roasted in order to destroy the urushiol resin before it can be consumed.
Cashew is one of the extremely nutritious nuts. This delicate and sweet nut is packed with energy, fiber, antioxidants, minerals, vitamins and phytochemicals. It is rich in minerals like manganese, potassium, iron, copper, zinc, selenium and phosphorus. It also contains B complex vitamins like pantothenic acid, thiamine, pyridoxine, riboflavin and folate. Cashew apple contains five times more vitamin C than most of the citrus fruits. However, Cashew is a high calorie food and each 100 grams serving of cashew provides 553 calories.
Cashew nut oil:
The cold compression method is used to extract oil from Cashew shells. This oil is extremely beneficial for maintaining healthy skin. The high concentration of essential fatty oil helps in retaining moisture of the skin. A rich source of vitamin E cashew nut oil can help prevent the signs of aging like fine lines and wrinkles, if used regularly in body massages.
Health Benefits of Cashew:
Like many other nuts even Cashew nut has a wide list of health benefits. Here, we look at some of the common benefits.
1. Dental health:
Researchers have found that the chemicals present in cashew nuts can kill gram positive bacteria and pervasive mouth afflictions that cause tooth decay. It is also believed that moderate consumption of cashew nuts can eliminate the abscessed teeth, although it is not yet proven.
2. Eye health:
Cashew nuts contain small amounts of zea-xanthin an important antioxidant, which gets selectively absorbed into the retinal macula lutea in the eye. This gives our eyes the protective UV ray filtering functions, preventing age related macular degeneration in the elderly.
3. Weight loss:
Cashew nut is a highly fatty food but with good fat and 75% of the fat is unsaturated. Unsaturated fats provide more energy to the body, facilitating the body’s metabolism. This can help one lose weight, only if consumed in moderation.
4. Brain function:
Our brain relies on two types of fats – polyunsaturated and monounsaturated fats for the production of it’s brain cells. Cashew contains both of these fats. It also improves oxygen circulation to the brain, which helps in enhancing one’s memory.
5. Heart health:
Cashews are rich in several mono unsaturated fatty acids like oleic and palmitoleic acid. These essential fatty acids help in lowering of the harmful low-density lipoprotein, while increasing the good cholesterol. Monounsaturated fatty acids can help in reducing the triglyceride levels, preventing coronary artery diseases.
Magnesium found in cashew nuts promotes healthy bone structure. It also contains calcium that prevents bone mineral density loss.
Safety Profile – Know Your Cashews Before Eating Them:
Anaphylaxis is a common allergy caused by cashew nuts. The reaction may range from breathing difficulty, lower abdomen pain, vomiting, diarrhea to hives. Anaphylaxis is mainly caused due to the chemical compound urushiol present in shells, nuts and cashew apples.
Cashew nuts may cause swelling of the face and other areas of the body.
Other common side effects of excess consumption of cashew nuts is vomiting and diarrhea, which are the body’s natural reaction to get rid of impurities. If left untreated, it can cause dehydration.
The main objective of cashew processing is to extract the healthy and tasty kernel from the raw nut. Now a days modern factories are designed to obtain more of the whole nut and shell oil from cashew fruits. Processing process is divided into – drying, shelling, removal of the testa, grading and packaging.
Harvested nuts are first dried in the sun for a few days. The dried nuts are further stored for 2 years before being shelled. The nuts are again roasted to extract the caustic shell oil and acrid fumes. The nuts are soaked in water before roasting to facilitate the rupturing of the shells. This makes the kernels slightly rubbery, limiting the breakage of kernels.
This is the most difficult operation in the processing of cashews. Shelling is usually carried out by using a special wooden mallets and pieces of bent wire. Mechanical shelling of the cashew nuts is difficult to design because of it’s irregular shape. The latest method is to cut a groove around the shell and place it in a modified centrifuge fitted with metal plates. The nuts are then thrown against the plates and are cracked by centrifugal forces. You can obtain 85% of whole kernels by this method.
3. Removal of the testa:
The kernels are dried to remove the thin, papery seed coat of the cashew nut. Drying makes the testa dry and brittle, so that they can easily be removed. Bamboo knives are used to remove the remaining traces if any.
The broken cashew kernels are sorted into grading schedules. This sometimes varies as per the exporter.
The kernels are dried to 3% moisture content before they are packed. Drying extends the shelf life and prevents rancidity and fungal infections. Nuts of export quality are packed in tins for longer shelf life.