Dehusking and milling process removes the outer part of paddy husker to make it edible. There are three main types of husking machine, which includes: stone dehullers, rubber roll and impeller type husker. Stone de-hullers are still common in tropical Asia, where BR is immediately milled with either an abrasive or friction mill. It has been reported that types of liner significantly affect the husking performance. It has also been reported that the Engleberg-type or steel hullers are no longer acceptable in the commercial rice milling sector, as they lead to low milling recovery and high grain breakage. Abrasive or friction type milling machines are used to remove the bran. It has been reported that the abrasive mill can over-mill readily. In the Engelberg or huller type mill, dehusking and milling are performed in one step with greater grain breakage. Using a dehusker before milling improves both the milling and head rice yields. During parboiling treatment the husk splits and loosen, which makes it easier for dehusking. The energy consumption during dehusking process is also induced by the severity of steaming treatment and it tended to have decreased with the increase of steaming time.

Rice is the staple food for nearly two-thirds of the world's population. Food components and environmental load of rice depends on the rice form that is resulted by different processing conditions. Brown rice (BR), germinated brown rice (GBR) and partially-milled rice (PMR) contains more health beneficial food components compared to the well milled rice (WMR). Although the arsenic concentration in cooked rice depends on the cooking methods, parboiled rice (PBR) seems to be relatively prone to arsenic contamination compared to that of untreated rice, if contaminated water is used for parboiling and cooking. A change in consumption patterns from PBR to untreated rice (non-parboiled), and WMR to PMR or BR may conserve about 43–54 million tons of rice and reduce the risk from arsenic contamination in the arsenic prone area. This study also reveals that a change in rice consumption patterns not only supply more food components but also reduces environmental loads. A switch in production and consumption patterns would improve food security where food grains are scarce, and provide more health beneficial food components, may prevent some diseases and ease the burden on the Earth. However, motivation and awareness of the environment and health, and even a nominal incentive may require for a method switching which may help in building a sustainable society.

Parboiling is an ancient method of rice processing, widely used in the developing countries like Bangladesh, India, Sri Lanka, and in some rice exporting countries. Parboiled rice (PBR) has been produced by both traditional and modern methods. Various parboiling devices and techniques have been developed. Modern methods are energy and capital intensive, and are not suitable for small-scale operation at village level. The local parboiling device consists of pottery to boiler, used for direct or indirect heating and single or double steaming, which consume a different amount of energy. Agri-residues are the main sources of energy for local parboiling, especially the residues of rice processing industries. However, sun drying is the common practice in local parboiling processes. A nearby pond, river, lake or tube-well is the source of the water for parboiling.

Parboiling treatment induces various physicochemical changes in paddy which play an important role in storage, milling, cooking and eating qualities. Although PBR is known to have a number of advantages, require more energy, water and time for processing and cooking than the untreated rice. The parboiling treatment gelatinizes the rice starch, improves the hardness of the rice upon drying, minimized the breakage loss and thus increases the milling yield. Over-parboiling resulted in over-opening of the husk components followed by bulging out of the endosperm which initiates surface scouring during milling and the resultant ground particles being lost into the husk and bran. However, incomplete or non-uniform parboiling produces white-bellied rice, which breaks easily during milling, and reduces the head rice yield. The parboiled rice produced in the boiler processes is considered to be suitable and better because it has greater customer acceptance and market value, but require a greater initial investment. The quality of PBR depends on the paddy, intensity of parboiling, drying condition and moisture content after drying, DOM and the milling devices

The rice whitener incorporates advanced techniques for whitening of brown rice. It uses the vertical abrasive grinding wheel top to bottom working principle.The rice is whitened very gently between grinding wheel & screen without distracting the original shape of the rice kernel. A specially designed aspiration system takes away the bran produced during the whitening process. This vertical rice whitening machine is equipped with a mechanism for adjusting the degree of whiteness. The accurate & precise assembly techniques ensure lowest broken content.

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