Abstract Thus, the objective of this work was to evaluate the performance of industrial drying and the quality of soybean grains using a direct-fire furnace automatically fed by wood chips. To represent the grains before drying, four samples were collected together with the sampling of the loads in the trucks carried out to classify the product in the storage unit. At drying, performance evaluations and specific energy consumption were carried out. The grains were evaluated for moisture content, germination, electrical conductivity, apparent specific mass, color, acidity index, and PAHs. Drying showed an average efficiency of 75.50%. The average chip consumption was 0.4403 kg of chip/kg of evaporated water. The specific energy consumption was 8,099.50 kJ/kg of evaporated water. The grains showed differences after drying in the characteristics of germination, electrical conductivity, and chroma. Six PAHs were detected in the samples before drying: (B(a)A, Chr, 5 MC, B(j)F, Dib(ai)P, and IcdP). After drying, in addition to the PAHs obtained before drying, five more were detected (B(b)F, B(k)F, B(a)P, Dib(al)P, and Dib(ah)A). Mean PAH concentrations were higher than the maximum values allowed by European Union legislation. Thus directfire direct fire chips unit content germination conductivity mass color index 7550 75 50 75.50% 04403 0 4403 0.440 chipkg water 809950 8 099 8,099.5 kJkg kJ chroma BaA, BaA B A, A (B(a)A Chr MC BjF, BjF j F, F B(j)F DibaiP, DibaiP Dib ai P, P Dib(ai)P IcdP. IcdP . IcdP) BbF, BbF b (B(b)F BkF, BkF k B(k)F BaP, BaP B(a)P DibalP, DibalP al Dib(al)P DibahA. DibahA ah Dib(ah)A) legislation 755 7 75.50 0440 440 0.44 80995 09 8,099. Dib(ah)A 75.5 044 44 0.4 8099 8,099 75. 04 4 0. 809 8,09 80 8,0 8,

Abstract The objective of this study was to evaluate the drying system using a dryer with furnace automatically fed with eucalyptus chips and another dryer manually fed with eucalyptus firewood, as well as assessing the quality of corn grains. Harvest was mechanically performed and the grains were transported by trucks to the storage unit for drying. Corn grain drying was conducted in mixed-flow dryers with a nominal capacity of 100 tons per hour. For air heating, two direct-fired furnaces were used, one automatically fed with eucalyptus chips and the other manually fed with firewood. Corn grains were evaluated for moisture content, apparent specific mass, thousand-grain weight, polycyclic aromatic hydrocarbons (PAHs), electrical conductivity and color. Drying corn grains with direct fire using firewood or chips as fuel causes contamination by PAHs. In general, the use of firewood or chips did not influence the quality of thousand-grain weight, apparent specific mass and color, while the use of chips increased electrical conductivity. It is essential that research advances in this subject, prioritizing the contamination of food, with proven carcinogenic activity, which should be treated as a high risk to public health.

O resfriamento artificial é uma ferramenta para conservação da qualidade de grãos nas regiões tropicais. Este trabalho foi realizado com o propósito de verificar o efeito da refrigeração artificial do ar, por meio de aeração, na preservação da qualidade de grãos de milho em armazém graneleiro horizontal, de fundo "V". Para o experimento foram utilizados dois septos, sendo um resfriado artificialmente (12ºC), com capacidade de 28 mil toneladas, e o outro aerado com ar natural, com capacidade de 29 mil toneladas. As amostragens foram realizadas, em ambos os septos, durante a carga, aos 60 e 120 dias após a primeira etapa de resfriamento e durante a expedição dos grãos. Durante o armazenamento, as amostragens foram realizadas considerando-se a posição e a profundidade da massa de grãos de milho. A avaliação qualitativa consistiu na determinação dos seguintes parâmetros: peso de mil grãos, temperatura da massa de grãos, teor e acidez de óleo, identificação de fungos, teor de aflatoxina, índice de infestação de insetos e porcentagem de grãos infestados. O resfriamento artificial promoveu a diminuição da temperatura da massa de grãos, independentemente das condições de temperatura e umidade do ar externo. A aeração artificial, com ar frio, preservou os parâmetros atribuídos à qualidade dos grãos e proporcionou redução na percentagem de grãos infestados e na população de insetos-praga na massa do produto. Assim, a utilização do resfriamento artificial no armazenamento de grãos de milho em regiões tropicais é eficaz na manutenção da qualidade dos grãos e no manejo de insetos e patógenos.

Artificial cooling is a tool used in the conservation of grain quality in tropical regions. In this study, we aimed to verify the effect of artificial cooling through aeration in preserving the quality of corn grains in bottom horizontal "V" warehouses. Two septa were used in the experiment: an artificially cooled (12ºC) septum with capacity of 28 thousand tons and a naturally aerated septum with capacity of 29 thousand tons. Sampling was carried out in both septa during loading, at 60 and 120 days after the first stage of cooling, and during expedition. During storage, sampling was performed considering the position and depth of the corn mass. A qualitative assessment was conducted to determine the following parameters: weight of thousand grains, grain mass temperature, oil content and acidity, identification of fungi, aflatoxin content, insect infestation rate, and percentage of infested grain. Artificial cooling temperature promoted a decrease in grain mass, regardless of the external conditions of air temperature and humidity. Artificial aeration, with cold air, preserved the parameters assigned to grain quality and provided reduced percentage of infested grain and reduced population of insect pests in the product mass. Therefore, the use of artificial cooling in the storage of maize grains in tropical regions is effective in maintaining grain quality and managing insects and pathogens.

The objective of this study was to evaluate the effects of genetic group and environmental factors, including farm of origin, season of calving and lactation number, on the individual lactation curves of 1,010 Holstein-Gyr, Guzerat-Holstein, Holstein-Nellore, and Holstein-Zebu F1 cows on the experimental farms of the Agricultural Research Company in Minas Gerais (Empresa de Pesquisa Agropecuária de Minas Gerais, EPAMIG). Least squares analysis and the incomplete gamma function were used to investigate differences in early milk yield, peak milk yield, time from onset to the lactation peak, persistency, total milk yield and lactation duration. The highest early yields were observed for Holstein-Gyr and Holstein-Zebu, and the lowest were observed for Holstein-Nellore cows. Early yield increased with lactation number, and the lactations that began in the late rainy and early dry seasons had the highest early yield. The time between lactation onset and the lactation peak was longer for primiparous Holstein-Gyr and Holstein-Guzerat cows. The lowest yields at the lactation peak were observed for the first lactation number. The highest values of persistency were observed for the first lactation number in Holstein-Guzerat cows. Total production from Holstein-Gyr and Holstein-Zebu cows were higher by approximately 14% and 29% compared with Holstein-Guzerat and Holstein-Nellore cows, respectively. The highest total yields were observed in lactations beginning in the dry season. Total yield increased with lactation number. The shortest lactation periods were observed in lactations beginning late in the rainy season. The incomplete gamma function was used to fit the individual curves from the genetic groups evaluated. The total yield differences were linked to early yields and yields at the peak of lactation.