Effects of milling ratio on technology evaluation and biochemical parameters, lipid profile and folic acid content in rice grains.

O arroz ?? o cereal que est?? presente na dieta alimentar de mais da metade da popula????o mundial. As agroind??strias intensificam as opera????es de polimento para obter gr??os mais brancos. Essa opera????o melhora a cor em rela????o ?? prefer??ncia do consumidor, por??m reduz conte??dos de nutrientes importantes para a alimenta????o. Objetivou-se, com este trabalho, avaliar efeitos da intensidade do polimento sobre par??metros de avalia????o tecnol??gica e bioqu??mica, perfil lip??dico e conte??do de ??cido f??lico em gr??os de arroz, com o intuito de fornecer subs??dios para ampliar o uso de tecnologias de industrializa????o, estimulando o aumento do consumo do arroz e seus derivados, com valoriza????o de sua qualidade nutricional. O trabalho foi estruturado em dois estudos, que englobaram tr??s experimentos. No Experimento I foram comparados par??metros de avalia????o qu??mica, tecnol??gica e de qualidade de consumo, perfil lip??dico e conte??do de ??cido f??lico em gr??os de arroz de dois subgrupos, integral e branco, obtidos por duas formas de beneficiamento convencional na produ????o industrial. No Experimento II foram determinados efeitos da intensidade de polimento na produ????o industrial de arroz branco sobre os mesmos par??metros do Experimento I. No Experimento III foram avaliadas as respostas biol??gicas de ratos machos adultos Wistar, cepa UFPEL, alimentados com dietas contendo arroz integral e branco polido em quatro intensidades no processo industrial. Os resultados permitem concluir que gr??os beneficiados pelo processo convencional, nas formas integral e polido, diferem significativamente quanto aos par??metros de avalia????o qu??mica, tecnol??gica e de qualidade de consumo, teor de ??cido f??lico e a resposta biol??gica de ratos machos Wistar. A intensifica????o do polimento na remo????o de farelo modifica significativamente par??metros de avalia????o qu??mica, tecnol??gica e de qualidade de consumo na coc????o, bem como o conte??do de ??cido f??lico, sem alterar os atributos sensoriais, o perfil lip??dico e a resposta biol??gica de ratos machos Wistar.Rice is the cereal present in the alimentary diet of more of the half of the world population. The agribusinesses intensify the milling operations to obtain larger whiteness of the grains by removing the most outlying layers of the grains. This process improves the color in relation to the consumer's preference; however, it reduces important nutrients for the human feeding. The objective of this research was to evaluate the effects of milling ratio on technology evaluation and biochemical parameters, lipid profile and folic acid content in rice grains, long-thin class, from irrigated cultivation of the South of Brazil. The work was structured in two studies, which encompasses three experiments. In Experiment I were compared evaluation parameters chemistry, technology and quality of consumption, lipid profile and folic acid content in rice grains of two subgroups, brown and white, obtained by two conventional forms of processing in industrial production. In Experiment II were certain effects of intensity in industrial production of polished white rice on the same parameters as in Experiment I. In Experiment III were evaluated the biological responses of adult male Wistar rats, strain UFPEL fed diets containing white rice and polished in four different intensities in the industrial process. The results suggest that grains by conventional, brown and polished in the ways, differ significantly to the chemical evaluation, technology and quality of consumption parameters, folic acid content and biological response of male Wistar rats. The intensification of the polishing removal of bran significantly modifies chemical evaluation, folic acid content, technology and quality parameters for human consumption in cooking, without altering the sensory attributes, lipid profile and biological response of male Wistar rats