<b>Yield and acidity indices of sunflower and soybean oils in function of grain drying and storage

Abstract

ABSTRACT. The aim of this study was to identify the best conditions for drying and storing soybeans and sunflower grains to maintain their quality. In the first experiment, the soybeans were found to have initial moisture contents of 25 and 19% (w.b.) at different drying air temperatures (75, 90, 105, and 120°C). In the second step, the soybeans were evaluated after they were stored in paper bags and plastic polyethylene at temperatures of 3, 10 and 23°C for six months. In the third experiment, sunflower grains were tested after exposure to drying air temperatures of 45, 55, 65, and 75°C, and under storage conditions of 25°C and 50%, 20°C and 60%, 30°C and 40% RH over six months in paper bags and raffia. Drying the sunflower seeds at 45°C and storing them at 30°C and 40% RH led to higher oil yields and lower acid numbers. The oil that was extracted from the acid number was higher for soybean grains that were dried down from initial concentrations of 25% water at a drying air temperature of 120°C. The air temperature in storage at 3°C favored for yield and reduction of the soybean oil acidity.Keywords: postharvest, processing and quality.Rendimento e índice de acidez do óleo de girassol e soja em função da secagem e armazenamento dos grãos RESUMO. Este estudo teve como objetivo identificar as melhores condições para secagem e armazenamento de grãos de soja e de girassol para a qualidade. No primeiro experimento, avaliou-se grãos de soja com umidades iniciais de 25 e 19% (b.u.) em diferentes temperaturas do ar de secagem (75, 90, 105 e 120°C). Na segundo etapa, avaliou-se grãos de soja armazenadas em sacos de papel e de plástico polietileno nas temperaturas de 3, 10 e 23°C, durante seis meses. No terceiro experimento, testaram-se grãos de girassol na secagem com temperaturas do ar de 45, 55, 65 e 75°C e condições de armazenagem de 25°C e 50%, 20°C e 60%, 30°C e 40% de UR do ar, ao longo de seis meses, usando sacos de papel e ráfia. A secagem de grãos de girassol a 45°C e o armazenamento na condição de 30°C e 40% UR forneceu maior rendimento do óleo e menores índice de acidez. O índice de acidez do óleo extraído da soja foi maior para os grãos submetidos à secagem com teores iniciais de água de 25% e na temperatura do ar de secagem de 120°C. O armazenamento na temperatura do ar a 3°C foi favorável ao rendimento e a redução do índice de acidez do óleo de soja.Palavras-chave: pós-colheita, processamento e qualidade.

Mathematical modeling and multivariate analysis applied earliest soybean harvest associated drying and storage conditions and influences on physicochemical grain quality

“…The results indicated that there were effects of the association of the conditions of harvest, drying, and storage on the quality of the grains. It is important to highlight that storage time was the main study factor that impacted the groups formed 53 .…”

Energy-Qualitative and Sustainable Impacts on Differents Soy Grain Drying Technologies

“…However, improper handling of the grain or drying system can cause serious damage to the grains. Coradi et al (2017) described how drying soybeans with water content above 19% and drying air temperature at 120 °C significantly increases the acidity and yield of crude oil and protein compared to drying at lower temperatures such as 75, 90 and 105 °C. Hartmann Filho et al ( 2016) evaluated soybeans with water content of 23% (w.b.…”

“…Although drying is a fundamental operation, the thermal process must be gentle in terms of time and temperature, because in addition to removing water, drying can interfere with the physicochemical structure of the grains, causing cell tissue disruption and accelerating the process of grain deterioration. Consequently, this may increase the acidity index and reduce the oil and protein content (Alencar et al, 2009;Coradi et al, 2017;Hartmann et al, 2016;Samadi et al, 2013).…”

Qualidade De Grãos De Soja Transgênica Rr E Intacta Rr2 Pro Na Secagem

“…De acordo com Coradi et al (2017) Pode-se observar que os valores de condutividade elétrica para ambas as variedades de soja aumentaram, de acordo com o aumento da temperatura do ar de secagem. Na variedade de soja RR, o lote de grãos úmido teve menores valores de condutividade elétrica com 50,45 (µS cm -1 g -1 ), enquanto que o lote de grãos submetidos à secagem a 35 °C teve valores de 86,41 (µS cm -1 g -1 ), o lote seco a 45 °C teve valores de 99,12 (µS cm -1 g -1 ), não apresentando diferença significativa entre as temperaturas de secagem de 35 °C e a 55 °C, que teve valores de 112,03 (µS cm -1 g -1 ) de condutividade elétrica.…”