Alternativas para as etapas de torra e despeliculagem no processo de beneficiamento de amêndoas de castanhas de caju.

Abstract

The removal of the cashew nut skin is largely responsible for the high rates of breakage of the almond and the frying stage has a direct influence on the color of the product. For these reasons, the biggest technological bottlenecks suffered by the nut processing industry are found in these two stages, although they are not the only ones responsible for the damages. The present work had as objective to develop new technological alternatives for the frying (drying / roasting) and dehulling stages of the cashew nuts and, to reach these objectives, it was necessary to study the variations in the physical characteristics of the almonds and after each stage of roasting and dehulling processing; study the drying kinetics of chestnuts, combining high drying temperatures 120, 140, 160 and 180 ° C with drying air speed, 3m.s-1, and adjust the models of Fick, Page, Cavalcanti Mata and Henderson & Pabis experimental data; develop equipment to depelicularize the nut, evaluating the parameters of the depeliculation index and minimizing the breakage index. For this, the method of drying through the system known as “air fryer” was used, specific methodologies to measure the physical properties of the almonds, preliminary studies of functional systems for the machinery and tests with prototypes for the development of the depeliculator, in addition to statistical treatments to compare the data obtained with the experiments carried out after using the developed equipment. It was possible to define ideal drying times and temperatures for the almond roasting that did not alter the physical properties of the nut, in addition to developing an efficient equipment, with about 75% of dehulled almonds, with a whole almond index of around 90%, with color uniformity for temperatures of 120 and 140 ° C, with accepted coloration for export-type nut.