Estudo reológico de solução filmogênica utilizando fécula de araruta (Marantha Arudinacea).

Abstract

Starches are widely used in the food industry as a raw material in various products, mainly to provide greater consistency to foods. The main sources of commercial starch in the world are corn, potatoes and cassava. The use and production of starch from arrowroot starch, an unconventional food plant, is still scarce, with few studies on the rheology of arrowroot starch solutions. Thus, this work aimed to rheologically characterize solutions based on arrowroot starch at different temperatures 40, 50, 60, and 70°C and at different rotation speeds: 50, 60, 70, 75, 80, 90, 100 , 105, 120, 135, 140, 150, 160, 180 and 200 rpm. The experiments were conducted in two stages: characterization of the raw material; preparation and analysis of the filmogenic solution. The raw material was characterized regarding water content, ash, acidity, pH and scanning electron microscopy. The different formulations of the film-forming solution were produced using a complete 2² factorial design with 4 axial points and three replications at the central point to study the effect of plasticizer and arrowroot starch concentration on the rheological properties of the solutions. The results demonstrated that arrowroot starch presented a value for water content below all the maximum percentages required by legislation, being within the recommended range and allowing safe storage. The pH values were equal to 5.89, while the acidity presented a value equal to 0.9 g/100g. The amount of ash found was 0.5 g 100 g-1, which indicates a pure raw material. The results of the morphology of arrowroot starch revealed that the starch granules have a rounded shape and a smooth surface without grooves or pores, with average sizes equal to approximately 18.65 ± 2.80 µm. The rheological behavior of the film-forming solutions of the fluid presented a non-Newtonian character and pseudoplastic behavior, the Herschel-Bulkley and Mizrahi-Berk models presented similar adjustments and were also the best models for all formulations studied with R² > 98%. and DQM values lows.