Four centuries ago, the adventurous Portuguese came sailing down the Indian coasts and brought with them the priceless tree nut - "Cashew", the wonder nut of the world. Cashew came, conquered and took deep roots in the entire coastal region of India. Cashew found the Indian soil more homely than its homeland. Later it spread as a popular crop to other parts of India. Cashew cultivation now covers a total area of 0.70 million hectares of land, producing over. 0.40 million M.T. of raw cashew nuts annually. By the end of the century India has targeted to achieve a production level of over 0.60 million M.T of raw cashew nuts. Cashew tree is a short, stocky, low-spreading, evergreen tropical tree. It flowers once a year, between the months of November and January. The fruit ripens fully within 2 months. The nuttiest feature of Cashewnut is that it is attached to the lower portion of the cashew apple which looks like a fruit, but in reality it is the enlarged stem of the cashew tree. The Cashewnut can be seen sitting smugly under the soft belly of the cashew' apple. Together, it is one of the fascinating sights of nature.The Cashewnut seed has within itself a whole kernel and this delicate kernel is covered by a testa membrane and a thick outer shell which effectively protects the tasty kernel from the ravages of nature from the time of harvesting to processing.In its raw form, the cashew kernel is soft, white and meaty. When roasted it changes colour and taste. The cashew kernel turns from a creamy white into a golden hue and the mellow pulp becomes crisp. Salted, it appeals to the palate as the most delicious nut. Cashewnut Processing
India was the first country to hit the world market with cashew kernels and it was she who pioneered cashew processing as an industry. India is the largest producer, processor and exporter of cashews in the world. The raw cashew nuts collected from the growing areas are moved to the factories for processing.. It is ensured that the raw nuts are thoroughly cleaned and are free from all foreign matter before they are taken for processing. The processing of cashew is done by any of the four methods -- Sun Drying, Drum Roasting, Oil Bath Roasting and Steam Cooking. Sun Drying is the raw cashew nuts are simply dried in the sun for a few days and shelled with out temp. In Drum Roasting, the nuts are heated at high temperature is a rotating drum and then shelled.In Oil Bath Roasting, the nuts get roasted in a bath or cashew shell liquid and also the cashew nut shell liquid (CNSL) is extracted. Steaming is another improved method adopted in Cashew processing. The nuts are steamed so as to make the shell soft and then cut open to get the kernel.The roasted /steamed rawnuts are opened by cutting or by using mallets and the testa is then removed after drying in a borma. The peeled kernels are then graded by size, shape and colour and packed for exports.The Cashewnut Shell Liquid (CNSL) is a by-product obtained during processing. This is an effective replacement of scarce and expensive petro chemicals. Before this liquid is utilized for various applications, it is treated to get rid of metallic impurities as well as traces of sulphur compounds. CNSL is described often as a versatile industrial raw material. It has wide application in the manufacture of friction lining materials, surface coating, lacquer, insulating varnishes, cement, composite wood etc.
Standard specifications for Indian cashew kernels for export have been laid down by the Government of India under the Export (Quality Control And Inspection) Act 1963. Characteristics of cashew processing technology
The most significant difficulty in processing cashew nuts is that the hard outer shell, which contains the edible kernel, contains a caustic oil which can burn the skin and produce noxious fumes when heated. Mechanized processing, using hot oil baths or drum roasting, followed by automated cutting...