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Fornecimento de flushing com silagem de milho moído e reidratado a cabras da raça Saanen
(Universidade Federal de Lavras, 2025-04-29) Dias, Brenda Veridiane; Alves, Nadja Gomes; Leite, Rafael Fernandes; Lima, Renato Ribeiro de; Bispo, Charles André Souza; Figueira, Lucas Machado
The objective was to evaluate the impact of replacing ground corn (GC) with rehydrated ground corn silage (RGCS) in flushing diets on productive performance, feeding behavior, metabolites, follicular development, and ovulations in Saanen goats. Thirty-six non-lactating goats were blocked by body condition score (BCS) and randomly assigned to one of three treatments: maintenance diet (control, n=12), GC flushing (n=12), or RGCS flushing (n=12) for 24 days. The estrus synchronization protocol began on the 12th day. Goats were weighed, and BCS and subcutaneous backfat thickness (SFT; mm) were measured on the day before feeding the diets (d-0; covariate) and on days 7, 14, and 21. Blood samples (days 0, 7, 14, and 21) were analyzed for glucose and urea. Feeding behavior was assessed (days 13-14) using 24-h scans at fiveminute intervals. Digestibility was evaluated via total fecal collection over five days, and apparent digestibility coefficients for dry matter (DM) and nutrients were calculated. Ovaries were assessed daily by ultrasonography from day 20 until ovulation. After 10 days, the corpora lutea was assessed. Analyses were performed in SAS software, with generalized models for intake, digestibility, feeding behavior, and reproductive data. Mixed models were used for metabolite concentrations. Treatment effects were compared using orthogonal contrasts: 1) control diet vs. flushing, and 2) GC vs. RGCS, with significance set at 5%. All nutrients, except NDF and ash, showed higher intake in flushing diets (GC and RGCS) compared to the maintenance diet (CON). Flushing diets with GC and RGCS did not differ (P>0.05) in terms of intake of DM, protein, ether extract, non-fibrous carbohydrates, and starch, indicating that both sources are equivalent. Final body weight was higher in the RGCS group (P<0.05). Plasma glucose concentrations did not differ between treatments (P>0.05). Plasma urea nitrogen (PUN) concentrations were lower (P<0.05) in goats fed flushing diets, suggesting better nitrogen utilization. On day 21, concentrations differed between goats fed GC and RGCS (13.0±1.26 mg and 8.3±1.24 mg dL⁻¹, respectively). Follicular growth was more pronounced in the flushing groups (P<0.05), but the total number of ovulations did not significantly differ between treatments (P>0.05). The number and diameter of follicles did not differ (P>0.05) between treatments, but a higher follicular growth rate (P<0.01) was observed in animals fed flushing diets. The number of ovulations was 1.47 in the control group, 1.18 in animals fed GC, and 1.94 in those fed RGCS (P>0.05). Total luteal area differed between flushing treatments and was greater in animals in the RGCS group (2.76 vs. 1.56; P<0.05). Goats fed flushing diets required less time for feeding, rumination, and total chewing activity. The feeding efficiency of DM and NDF was greater in animals fed RGCS, and a higher number of chews per ruminal bolus was observed in these animals. It was concluded that replacing GC with RGCS in flushing diets does not impair feeding behavior and improves DM and NDF efficiency, resulting in higher weight gain. Flushing diets resulted in a higher follicular growth rate, with a greater total luteal area observed in the RGCS diet.
Propriedades de painéis aglomerados de madeira com a substituição de Pinus oocarpa por resíduo de babaçu (Attalea SPP.)
(Universidade Federal de Lavras, 2026-01-21) Ribeiro, Pedro Henrique Garcia de Castro; Guimarães Júnior, José Benedit; Oliveira, Bárbara Maria Ribeiro Guimarães de; Batista, Felipe Gomes; Arantes, Lorran de Sousa; Lago, Rafael Carvalho do; Silva, Evandro Pereira da
Wood particleboards, widely used in the furniture, coverings, and civil construction sectors, play an essential role in optimizing the use of forest resources and promoting sustainability. The continuous improvement of their physical, mechanical, microstructural, and thermal properties has driven the search for alternative raw materials. In this context, the present study aimed to evaluate the properties of lignocellulosic composites produced on a laboratory scale by gradually incorporating Attalea spp. residue as a substitute for Pinus oocarpa in proportions of 0, 25, 50, 75, and 100%. The Pinus oocarpa particles and Attalea spp. residue were processed and classified to obtain the desired particle size distribution. The panels, measuring 25 × 25 × 1.5 cm with a nominal density of 0.75 g/cm³ (medium density), were manufactured using 90 g of urea–formaldehyde adhesive per unit. A manual pre-pressing was first carried out at room temperature under a pressure of 0.42 MPa, followed by hot pressing under the following parameters: 10 minutes, 4 MPa, and 150°C. The chemical properties of the lignocellulosic materials were analyzed. The physical properties of the panels were evaluated through tests of apparent density, compaction ratio, water absorption, thickness swelling, and thickness recovery rate. For the mechanical properties, static bending (modulus of rupture and modulus of elasticity) and internal bond strength tests were performed. Microstructural characterization was conducted using scanning electron microscopy and stereoscopic microscopy with fluorescence. The thermal properties of the panels were also analyzed. The treatment with 50% substitution showed the best performance in thickness swelling and thickness recovery rate, while the treatment with 25% substitution exhibited satisfactory mechanical results, achieving the highest internal bond strength. The panels containing 75% substitution presented the best thermal conductivity performance. Overall, all treatments met the requirements of technical standards for particleboards intended for indoor use under dry conditions, demonstrating the technical and environmental feasibility of using Attalea spp. residue as a sustainable alternative raw material for particleboard manufacturing.
Biocarvão de borra de café pelo processo hidrotermico com níquel (ii) ou cobre (ii) como precursor de carvão ativado
(Universidade Federal de Lavras, 2025-09-26) Alves, Rafael Pereira; Guerreiro, Mário César; Bianchi, Maria Lucia; Caetano, Aline Aparecida
Brazil, the world's largest coffee producer, generates large volumes of coffee grounds as waste, approximately 450 kg of dry grounds per ton of coffee processed. This work proposes the reuse of this byproduct as a carbonaceous precursor for the production of hydrochars by hydrothermal carbonization (HTC) catalyzed by metal ions (Ni2+ and Cu2+) and, subsequently, of activated carbon by physicochemical activation. The HTC process was conducted in the absence and presence of metal ions (Cu2+ and Ni2+), with the aim of evaluating their catalytic influence. The results demonstrated that HTC promoted the formation of carbonaceous and polyaromatic structures, with higher yields in hydrochars prepared with metal ions (Cu2+ and Ni2+), highlighting the catalytic effect of these ions in the hydrolysis, dehydration, and repolymerization reactions of the biomass. After physicochemical activation, the carbons presented estimated surface areas of 801 m2·g−1 (AC-Cu) and 729 m2·g−1 (AC-Ni), while the reference carbon Alpha-W810, evaluated by the same method, exhibited an area of 502 m2·g−1. In the methylene blue isotherms, the AC-Cu and AC-Ni carbons exhibited maximum adsorption capacities of 415 mg·g−1 and 378 mg·g−1, respectively, values higher than those obtained for the Alpha-W810 carbon (260 mg·g−1) under the same conditions. The isotherms were best fitted by the Langmuir model, confirming adsorption onto homogeneous monolayers, while the kinetics followed the pseudo-second-order model, suggesting a predominance of chemisorption. In summary, metal ion-catalyzed HTC proved to be an efficient strategy and, when combined with physicochemical activation, demonstrated the potential to produce activated carbons with high adsorptive performance, suitable for applications as adsorbents in the treatment of aqueous effluents and environmental remediation.
Compostos orgânicos voláteis em queijos minas artesanal de casca florida natural: estudos aplicados ás microrregiões da canastra e de Diamantina
(Universidade Federal de Lavras, 2025-07-17) Mansur, Bethânia Leite; Saczk, Adelir Aparecida; Magalhães, Elisângela Jaqueline; Botelho, Bruno Gonçalves; Boari, Cleube Andrade; Abreu, Luiz Ronaldo de; Pedroso, Marcio Pozzobon
Minas Gerais artisanal cheeses have achieved national and international awards in competitions. The traditional method of producing Artisanal Minas Cheese has been designated as Intangible Cultural Heritage of Humanity by UNESCO, underscoring its cultural significance. The primary objective of this study was to deepen the understanding of the volatile compound profile in Natural Bloomy Rind Artisanal Minas Cheese (NBRAMC) and Artisanal Minas Cheese produced in the Diamantina microregion. Emphasis was placed on regional identity and the influence of factors such as ripening time, production practices, and seasonal climatic conditions, utilizing HS-SPME coupled with GC-MS, alongside chemometric analyses such as Principal Component Analysis (PCA) and Partial Least Squares Discriminant Analysis (PLS-DA). In the first article, NBRAMC samples were analyzed, and 67 volatile compounds were identified. PCA revealed that the primary differentiation among samples was attributed to the cheese portion analyzed (surface or core), rather than ripening time or producer. The second article focused on the influence of climatic conditions (rainy and dry seasons) on the volatile compound profile of artisanal cheeses from the Diamantina microregion. Although PCA was unable to clearly group samples based on seasonality or cheese portion (surface or core), PLS- DA demonstrated a high classification capability between samples from the rainy and dry seasons. This indicates that, despite not being visually apparent in reduced dimensions, volatile patterns exist that allow for the discrimination of samples by seasonality. Supporting literature reinforces that the microbiota of artisanal cheese, and consequently volatile compound production, is significantly affected by seasonal conditions, including temperature and humidity variations, as well as pasture composition, which directly influences the milk. In conclusion, this thesis demonstrated the complexity and dynamism of the volatile compound profile in artisanal cheeses, revealing that both the producer's "know-how" and seasonal environmental conditions significantly impact the final product's sensory characteristics. The identification of these volatile compounds and the ability to classify them by various factors contribute to the cultural, social, and economic valorization of Brazilian artisanal cheeses, providing important tools for the authenticity and quality control of these products.
Potencial biotecnológico de leveduras para elaboração de cervejas com baixo teor alcoólico com e sem jenipapo
(Universidade Federal de Lavras, 2025-08-22) Casimiro, Lucas Kenzo Shimabukuro; Schwan, Rosane Freitas; Bressani, Ana Paula Pereira; Dias, Disney Ribeiro; Junqueira, Mateus da Silva; Dragone, Giuliano Marcelo; Magalhães, Karina Teixeira
Beer is one of the most consumed alcoholic beverages in the world, and the craft beer market has expanded significantly, driven by the search for products with sensory appeal and added value. In this context, there is growing interest in the use of natural ingredients that offer different sensory characteristics. Genipap, a fruit native to the Amazon and the Brazilian Cerrado, stands out for containing genipin, a compound capable of forming natural blue pigments and conferring distinct sensory characteristics, making it a promising alternative in the production of craft beers. Growing consumer health concerns have stimulated the development of reduced-alcohol beers, considered lighter and more balanced. Thus, the use of genipap combined with selected yeasts represents an innovative strategy to produce low-alcohol beers with different sensory attributes. The objective of this study was to evaluate the biotechnological potential of different yeast strains in the production of reduced-alcohol beers, with and without the addition of genipap extract. Pre-tests were performed for yeast selection, followed by physicochemical analyses, including pH, soluble solids, apparent attenuation, cell count, quantification of organic acids, carbohydrates, volatile compounds, total phenolics, antioxidant activity, and sensory evaluation. In tests without genipap addition, the yeast Saccharomyces cerevisiae CCMA 2122 showed greater attenuation (51.3%) and organic acid production (1.92 g/L) compared to Pichia kluyveri CCMA 0615. P. kluyveri, in turn, produced beers with a lower alcohol content (2.20% v/v) and a more complex aromatic profile, resulting from the formation of different esters. Sensory analysis indicated greater acceptance of the beer fermented with S. cerevisiae, which obtained higher average scores for aroma (7.2), flavor (7.1), and overall impression (7.1). In formulations with added genipap extract, the CCMA 2122 strain resulted in beers with higher alcohol content (3.05% v/v), lower carbohydrate content (2.69 g/L), greater citric acid production (1.45 g/L), and a volatile profile associated primarily with the formation of alcohols and hydrocarbons. Sensorially, these samples were associated with the "happy" emoji ( ) after tasting. The P. kluyveri CCMA 0615 strain produced beers with lower alcohol content (2.39% v/v), higher carbohydrate concentration (5.73 g/L), a volatile profile rich in esters and acids, and higher total phenolic compounds content (545.09 mg AGE/L). Co-inoculation of the strains produced beers with intermediate ethanol and carbohydrate contents, as well as greater bioaccessibility of bioactive compounds (55.7% for total phenolics, 56.09% for FRAP, and 50.18% for ABTS). In the acceptance test the overall average score for all treatments was approximately 6.0, indicating that consumers slightly enjoyed the beverage. Overall, the S. cerevisiae CCMA 2122 strain exhibited the best fermentation performance, making it suitable for both conventional and low-alcohol beers. The P. kluyveri CCMA 0615 strain stood out for producing aromatic and distinctive beers, while co-inoculation showed potential for the development of balanced beers with enhanced functional and antioxidant characteristics.