The present research had the objectives of determining the in natura potato tuber centesimal composition in the distilling process in order to produce ethanol and to verify the solid residues resulting from this tuber fermentation process. Based on the residue composition, it was evaluated the effect of its use in the substitution of different dietary fiber content of a standard diet observing the rats biological response to this diet. In order to evaluate the biological effect, 32 Wistar rats were used divided into four groups. One group was given the standard diet for growing rats, according to recommendations of the American Institute of Nutrition (AIN-93), and the other three groups were given this diet substituting 25, 50 or 100% of residue by dietary fiber. Throughout the experimental period (23 days), consumption, weight gain, food efficiency ratio (FER), dry and moist feces production, pH and nitrogen fecal excretion were evaluated. At the end of the experiment, liver and epididimal fat weights, triglycerides, total cholesterol, HDL cholesterol and total protein levels were evaluated. The residue presented centesimal composition of 8.2% protein, 16.7% of dietary fiber, 62.8% of carbohydrates and 288 Kcal. The results obtained in the biological assay suggest that the solid residue resulting from potato tuber fermentation can be employed as a source of nutrients having as basis the exchange of fiber fraction of an AIN-93 standard diet without endangering rats' growth and the analyzed biochemical parameters.
Solanumtuberosum L.; fermentation residue; centesimal composition; biological effects
