Métodos utilizados para determinação dos constituintes da fração fibrosa, uma revisão

The estimation of the chemical-bromatological composition of foods involves a series of studies that mainly evaluate the fibrous fraction, since it presents great variability when compared to the other components. The growing number of publications on the analytical techniques available for determining the nutritional value of food end up generalizing the use of poorly defined terms. There are several techniques for evaluating forage components, the detergent system being the most used, although there are more modern methods. However, the accessibility and cost of these modern methods are factors that limit their use in various laboratories. Moreover, some of these methods are not recognized as an official method of analysis. In this context, the objectives of this review were: to highlight the most important concepts in determining the nutritional value of foods; improve the use and difficulties of interpretation of analytical results. It was concluded that the use of analytical methods allows to estimate the composition and availability of different fractions of the cell wall. But variability of cell wall constituents requires knowledge of the different analytical methodologies available. Analytical methods, traditional or alternative, are still empirical as they present different results for the same analysis. These variations are mostly generated by the differences between the steps of the analytical procedures. It is clear that the improvement of analytical methods is extremely important for estimating the nutritional value of foods.