Parboiling

Rice hulls are rich in cellulose, lignin, and silica and have low nutritional value even for ruminants (Chapter 18). As a result, rice hulls are usually used for combustion-pyrolysis in rice mills and parboiling plants. The hulls are less efficient than coal in terms of energy released and produce more ash, which requires a more sophisticated grating system. Hulls are also used as poultry litter, although other litters are considered to be of better quality. The pure silica obtained from rice hulls is used to produce solar cells and microchips. 

Rice bran, consisting of the pericarp, seed coat, germ, and aleurone tissues, accounts for 7%-10% of the rough rice weight. The bran is rich in protein, fat, minerals, and B-vitamins (Juliano and Bechtel 1985) (Chapter 18). In Asia, rice bran is used as a raw material for production of rice oil. Both mechanical expellers and hexane extraction systems are used. Solvent extraction usually yields 16%-18% oil and defatted rice bran with less than 1% residual oil, whereas mechanical pressing leaves around 10% oil, yielding partially defatted rice bran prone to oxidation. Recently, whole stabilized and defatted rice bran has been viewed as a source of important antioxidants and nutraceuticals with health-promoting effects. In Europe and America, rice bran is mainly used as poultry, cattle, and swine feed (Chapter 18). 

Parboiling is defined as a hydrothermal process applied to rough rice in order to achieve high milling yields (Amato and Silveira 1991, Battacharya 1985). The 

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The three principal domestic uses for rice in 1988 were direct food (61%), processed food (18%), and beer (20%). The direct food use figure includes the conventional white milled rice plus specialty rice products (parboiled, precooked, aromatic, brown, and prepackaged mixes) shipped directly from the rice mills. The specialty products account for approximately one-fifth of the direct food use. Approximately two-thirds of the direct food use rice is ultimately distributed to consumers through retail outlets and one-third through food service outlets. 

Ansbrueh, m. wine of the first press outburst, outbreak, explosion, eruption excavation, auabriihen, v.t. scald, parboil. 

Ushakumari et al. (2007) developed a process for the preparation of expanded ragi. After parboiling and decortication, the grains were conditioned to 40% moisture, flattened in a roller flaker, and then toasted in salt maintained at 220-225 °C for 6 s. Shape factor (ratio of measurements on two peripendicular axes), the expansion ratio (ratio of the volume of expanded millet to that of the decorticated millet of equal weight), apparent bulk density (volume of known weight of expanded millet), and sensory characteristics were the criteria used. The optimum conditions to prepare a product with the highest expansion ratio was then determined. 

Jayasekera and Freitas were the first to investigate the content of 24 chemical elements in rice grain and flour from Sri Lanka [19]. The purpose of their study was to compare the data obtained with the maximum permissible levels prescribed by international guidelines. Determinations were made by means of INAA with k0 standardization. The rice samples were collected from local markets and were representative of two major varieties, raw polished and parboiled rice. Prior to analysis, samples were freeze-dried and ground to fine powder. The CRM IAEA V-8 rye flour was used to check the accuracy of experimental... 

Sample Collection Ten rice samples of Italian origin (five of which were parboiled) and 11 samples from Asian countries were obtained from Italian retailers. The Asian samples were from China (three), Thailand (two), Bangladesh (two), Sri Lanka (one), India (one), Pakistan (one), and Philippines (one). 

For the essential elements, higher concentrations were found in Asian rices, even though, in both cases, their levels are comparable with those obtained in previous studies [10, 42]. The observed ranges of concentration for Asian and Italian samples, expressed in nanograms per gram, are respectively as follows Co, 4-26 and 4-14 Cu, 1015-3005 and 961-2291 Fe, 1893-9949 and 1363-3673 Mn, 5505-17,612 and 3544-11,371 Zn, 6762-20,337 and 5977-18,574. In more detail Mn and Zn levels in parboiled Italian rice (see Table 12.2, rice varieties 5 through 9) were lower than in Asian rice, which may be a consequence of... 

R. J. B. Heinemann, P. L. Fagundes, E. A. Pinto, M. V. C. Penteado, U. M. Lanfer-Marquez, Comparative study of nutrient composition of commercial brown, parboiled and milled rice from Brazil, J. Food Comp. Anal., 18 (2005), 287-296. 

Parboiling of rice is also an example of wet heat stabilization. The lipase in rough rice is completely inactivated by either autoclaving for 3-20 minutes or by parboiling. 

The color of crude rice bran oil is dark greenish brown to light yellow depending on the condition of the bran, extraction method, and composition of the bran. The pigments include carotene, chlorophyll, and Maillard browning products (12, 28). Oil from parboiled rice bran is generally darker in color than oil from raw rice bran. 

Padmaja, G., Premkumar, T., Plumb, V., Bainbridge, A., and Wood, J.F. 1994. Amino acid and sugar profiles of insect infested and uninfested plain-dried versus parboiled cassava chips. Trop. Sci. 34, 409 415. 

Sudhakar, T.R. and Pandey, N.D. 1987. Changes in chemical constituents of raw and parboiled rice varieties due to infestation of rice weevil Sitophilus oryzae (L.). Indian J. Entomol. 49, 1-6. 

Parboiled rice 90004 Focus - 128 channel, 4 gravity chute, monochromatic sorting machine Remove spotted, discoloured rice and foreign material (stones, glass, paddy, etc.) 5 to 10... 

Sorghum and pearl Parboiling, Nutritional value Serna-Saldivar et al. 

Serna-Saldivar, S.O., Clegg, C., Rooney, L.W. 1994. Effects of parboiling and decortication on the nutritional value of sorghum (Sorghum bicolor L. Moench) and pearl millet (Pennisetum glaucum L.). Journal of Cereal Science 19 83-89. 

Barley Water. Wash away with cold water all extraneous matter from 5 ounces pearl barley then boil for a short time in i pint water, throw this away, and boil the parboiled barley in 4 pints water down to 2 pints, and strain. 

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