Aplicação do processamento digital de imagens na caracterização de propriedades físicas de feijão ‘brsmg realce’ durante a secagem e estudo da qualidade física de grãos de bico ‘brs cristalino’ armazenados em diferentes embalagens

Abstract

Changes in the physical properties of the grains during drying have been widely studied, emphasizing their interference in the design of the equipment used in the post-harvest, and also during the storage with influence on the quality. Thus, this work aimed to determine the physical properties by digital images during drying of 'BRSMG Realce' beans and the quality of 'BRS Cristalino' bean during storage in different packages. The physicals properties of bean grains have been used since the use of orthogonal axes (length, width and thickness) by two methods of use: caliper and digital image analysis, using for photos displayed in the storage position and horizontal grain, an end to get the different axes in the digital camera. The methods were compared for each water content studied: 25, 23, 21, 19, 17, 15, 13 and 11% (wet basis). Therefore, the experiment was conducted in a randomized open design with three replications. From these data were used, by the average of 20 grains per repetition, the values of sphericity, circularity, grain unit mass, porosity and volumetric contractions of mass and grain unit, comparing by the test, the different measurements, in each water content. Also used during drying were a mass of 100 grains and an apparent specific mass. Determination of chickpeas quality, or the experiment was conducted in a casual casual design, in a 2x5 factorial scheme, consisting of two packages: Kraft paper and low density polyethylene bags, analyzed during five times of use: 0, 30, 60, 90 and 120 days, with estimates every 30 days. The product was kept under environmental conditions, from October to March (spring-summer). During this period, the following characteristics were used: apparent and unit specific mass, porosity, 100 grain mass, mass variation, coloration (luminosity, hue angle and chroma), as well as uniaxial grain variation. Both experiments were carried out at the Agricultural Products Drying and Storage Laboratory at Goiás State University in Anapolis-GO. The digital image analysis program, developed to analyze the bean grain axes, presents satisfactory results, the values considered as "optimum" for axis "a", "optimum" for axis "b" and axis "C" between "great" and “very good” in most of the analyzed water contents. Furthermore, we found no differences in the media data obtained from the different methods of using the axes (P> 0.05). During drying of bean grains, there was a linear trend to reduce orthogonal axes: length, width and thickness, as well as sphericity, circularity and mass of 100 grains (P≤0.05). However, for an apparent and unit specific mass and porosity, a reduction in the water content provided or an increase thereof. A volumetric contraction unit was estimated at 22.04% for axle capture by digital caliper and 28.63% for digital images, in the studied water contents. The adjusted model was exponential for measurement measurements, although for a volumetric contraction of bean grain mass or the best model was polynomial for image analysis and exponential for caliper recording, however, acceptable results, which kind of polynomial model can be used in two methodologies. Thus, the method of digital image analysis is viable. Already during the storage time, the chickpeas were influenced by the atmospheric conditions of the place, changing its initial water content and the remainder realized. Kraft paper packaging in the period analyzed presents the best results compared to low density polyethylene plastic packaging, with higher values of apparent density, higher brightness and chroma. A variation in mass, however, was greater for Kraft paper. A unit specific mass and a percentage of chickpeas do not differ in the reduction factors. The uniaxial compression of the grains shown, the quadratic behavior, with greater resistance to the end of the storage period, regardless of the packaging used. Thus, physical quality was influenced by environmental conditions, packaging and storage period.