AVALIAÇÃO DA QUALIDADE DA PROTEÍNA DE ARROZ E FEIJÃO E DE DIETA DA REGIÃO SUDESTE DO BRASIL

Surveys to obtain data on food intake have been carried out and analyzed to fi nd out if the intake supplies the nutritional requirements. Protein adequacy, like that of other nutrients, depends on several factors, besides the amount available to the body. Knowledge of nutritional value is essential to an assessment of dietary quality and to make a diagnosis of protein defi ciency. In this study, the protein quality of food items in the lowincome diet in southeast Brazil was evaluated. The indices Protein Effi ciency Ratio and Apparent Digestibility were used. The amino acid profi le was evaluated by means of food composition tables. The evaluated food items, taken from IBGE surveys, were prepared, dried and powdered to obtain the experimental feed for the diet group. A rice and dried beans mixture was also tested. In the biological assay, 18 rats were fed on the experimental feeds (diet or rice and beans) or standard casein feed. Controlled measurements of weight, feed intake and collected feces were performed. The results showed lower indices in experimental groups than in the casein group. Digestibility was considered the most relevant factor in protein quality for the rice and beans group. For the diet group, the digestibility was 81% and limiting amino acids were threonine and sulfur amino acids. Thus, the protein quality, measured by its digestibility and chemical score, was inadequate both in mixed rice and beans and in the typical food items eaten by the study population