Caracterização química e tecnológica de soja BRS 232 de diferentes safras

Abstract

Soybean [Glycine max (L.) Merrill] is the grain of greatest emphasis grown annually and is part of the set of agricultural crops with greater prominence in the world market due to its productive potential, its chemical composition and nutritional value that gives it a multiplicity of applications in human and animal nutrition. Soybean is influenced by numerous intrinsic and extrinsic factors throughout its cultural cycle and also during storage. During the storage stage, which begins in the post-harvest and goes through the industrialization process, the grains may undergo changes in their composition due to the storage environment. The objective of the work was to evaluate and compare the proximal composition and the techno-functional aspects of soybeans from cultivar BRS 232 from different harvests. The grains from the 2015/16, 2016/17, 2018/19 and 2019/20 harvests were donated by EMBRAPA Soja, which were grown in Ponta Grossa / PR, and were stored in a cold chamber (± 7ºC) until the time of analysis. The proximal composition showed that the major nutrient is protein (~ 36%), followed by carbohydrates (~ 28%) and lipids (~ 21%), the ash content was 5% and moisture (~ 9%) it was suitable for grains that are stored for more than a year. The grains of the analyzed crops did not show any significant difference for the swelling volume (~4mL.g-1). The soybeans of the 2015/16 crop showed the highest AAI and the lowest OAI, when compared to the other samples, probably due to the changes that can happen during the storage of the grains for long periods, since this was the sample with the longest storage. These grains also showed the highest density, differing from the others. The X-ray diffraction analysis showed a high intensity peak around the 2θ angle equal to 20° in all samples, indicating the crystalline region, and a peak at 35° was not seen in the sample with the shortest storage time (harvest 2019/20), suggesting that storage causes changes in the crystallinity of the grains. These peaks mainly represent cellulose from the hull, since the soybeans were completely crushed and it can be said that the material is mostly amorphous. The luminosity showed an intermediate value (~ 57) and the parameter b* (~ 26) showed yellow color, in both there was no significant difference, since the coordinate a* indicated the red color of the grains, varying from 5.47 to 8.02, showing statistical difference between the analyzed samples.