Processo de desintoxicação da torta de mamona destinada à ração animal: secagem e simulação.

Abstract

The castor bean is the main by-product of castor oil production chain, produced from the extraction of oil from its seeds. Around the world, its use has been rife as organic fertilizer, despite its high protein content. The bean is produced in the ratio of approximately 1.2 tons for every ton of oil extracted. The high production of bio-fuel from the seeds of castor lead to an increase in the production of the bean, which, despite its high nutritional value, cannot be used for animal consumption, for possessing toxic protein (ricin) to allergen (2S albumin). The aim of this work was to study methods of detoxification and drying of castor bean to be able to take advantage of it as animal feed. The characterization and chemical, physical-chemical and physical composition of the bean "in nature" were established by analysis of the levels of water, oil, protein, carbs, ricin, pH, nameable acidity, ash, fiber, calories and specific heat. The humidity equilibrium contained in castor bean was determined by the static method, in salt solutions and distilled water to a relative humidity range of 10, 30, 50, 70 and 90% at temperatures of 15, 25, 35 and 45° C. Samples from the castor bean were placed in sealed containers containing salt solutions in a chamber with controlled temperature, until they achieve equilibrium. For adjustment of the sorption isotherms of the castor bean Halsey, Henderson, modified by Thompson, Oswin and Cavalcanti Mata models were used, and experimental data subjected to nonlinear regression analysis using a computer program Statistica7.0. With the exception of the Oswin model, the others sufficiently described the behavior of the humidity equilibrium isotherms for the relative humidity and studied temperatures, with the values of the coefficients of determination (R2) superior to 99% and average percent deviations (P) inferior to 10%. We found that the humidity of hygroscopic equilibrium is directly proportional to the water activity and decreases with the increase of temperature, to the same value for water activity. The detoxification process of the castor bean was made by basic hydrated calcium hydroxide Ca(OH)2 in aqueous solution at concentrations of 1, 2, 3, 4 and 5%. The drying of castor beans was made at temperatures of 50, 60, 70, 80 and 90° C, in a fixed bed dryer, in thin layers, with satisfactory adjustments of the mathematical models of com Henderson, Page, Midilli and Cavalcanti Mata. The thick layered drying xxi occurred in temperatures of 50, 70 and 90°C, in the concentrations of 1, 3 and 5% and the isotherms adjusted by the Thompson model, showing a coefficient of determination superior to 99%. After treatment and drying, the quantification of the castor bean was done, referring to the chemical and physical-chemical parameters, finding alterations in the pH content and acidity, caused by the increase in concentration; as to the ricin content, it was verified that the higher the concentration of calcium hydroxide present in the treatment and the drying temperature, the more it was removed, reaching 0% of ricin in the concentration of 5% and the drying temperature of 90°C, making it edible for animals.