http://repositorio.ufgd.edu.br/jspui/handle/prefix/1624 2026-01-22T05:24:13Z http://repositorio.ufgd.edu.br/jspui/handle/prefix/6785 Título: A qualidade físico-química e microbiológica do músculo Longissimus dorsi em diferentes tempos de armazenamento Autor(es): Alves , Erica Mirian Teixeira Primeiro Orientador: de Goes, Rafael Henrique de Tonissi e Buschinelli Abstract: This study aimed to evaluate the physicochemical and microbiological characteristics of beef sirloin (Longissimus dorsi) sold in the city of Dourados-MS, over different storage periods. The samples were purchased from a local butcher and stored in polystyrene trays covered with plastic film. The experimental design was completely randomized, with 20 trays distributed across five shelf-life periods, each with four replications. Analyses included pH, color (CIELAB system), water-holding capacity (WHC), cooking loss (CL), shear force (SF), proximate composition (dry matter, crude protein, ether extract, and ash), and microbiological evaluation (coliforms, Staphylococcus spp., Salmonella spp., molds and yeasts). Results showed significant pH variations (5.47 to 5.79) during storage, within the expected range for good-quality meat. Color parameters changed, with a decrease in redness (a* = 19.48 to 13.43) and an increase in yellowness (b* = 4.83 to 8.12), indicating myoglobin and lipid oxidation. WHC increased from 80.61% to 90.28%, enhancing juiciness, while CL ranged from 23.85% to 44.54%, indicating greater liquid loss during cooking. SF decreased from 9.29 kgf to 2.84 kgf, reflecting improved tenderness. Proximate composition showed 62.86% dry matter, 15.94% crude protein, 3.29% ash, and 33.98% ether extract. Microbiological results showed the absence of Salmonella spp., Escherichia coli, coagulase-positive Staphylococcus, and coliforms, with counts of mesophilic aerobes (<3.0 × 10¹ CFU/g) and molds and yeasts (<3.0 × 10 CFU/g) within legal limits, indicating good sanitary quality. It is concluded that storage time significantly influences the physical and sensory quality of the meat, improving tenderness and water retention capacity, although increasing cooking loss. The meat was considered microbiologically safe and nutritionally suitable for consumption during the evaluated periods. Editor: Universidade Federal da Grande Dourados Tipo: Trabalho de Conclusão de Curso 2025-07-04T00:00:00Z http://repositorio.ufgd.edu.br/jspui/handle/prefix/6784 Título: Análise das estratégias de controle de temperatura em uma estufa de secagem Autor(es): Rossi, Weslen Felipe Magri Primeiro Orientador: Gibelli, Gerson Bessa Abstract: This work presents the development and simulation-based evaluation of control strategies applied to a laboratory drying oven whose original commercial controller became non operational. The thermal dynamics of the system were experimentally characterized, allowing the identification of a First Order Plus Dead Time (FOPDT) model capable of representing the oven’s heating behavior under disturbances and variations in power. Based on this model, a Proportional–Integral (PI) controller was designed using Internal Model Control (IMC) tuning rules, and a static feedforward action was incorporated to anticipate the steady-state power required to reach a given temperature setpoint. The performance of the PI+FF strategy was compared with the traditional On-Off control in multiple operating conditions, including different temperature setpoints and abrupt drops in temperature simulating door opening. The results show that the PI+FF controller eliminates oscillations, improves transient response, enhances temperature accuracy, and achieves higher energy efficiency for low and medium thermal loads. In contrast, the On-Off approach exhibited substantial oscillations, potential actuator stress due to frequent switching, and limited capability to maintain high temperatures with stability. The findings indicate that physical implementation of the PI+FF controller is a feasible and effective solution to restore and improve the oven’s operation, offering a robust alternative for high-inertia thermal processes. Editor: Universidade Federal da Grande Dourados Tipo: Trabalho de Conclusão de Curso 2025-12-10T00:00:00Z http://repositorio.ufgd.edu.br/jspui/handle/prefix/6777 Título: Análise de componentes principais no estudo de medidas de ultrassom in vivo em animais da raça nelore Autor(es): Boveda, Brenda Beatriz Dutra Primeiro Orientador: Seno , Leonardo de Oliveira Abstract: Carcass ultrasound is a valuable tool for evaluating traits associated with meat quality, offering accurate, low-cost, and rapid in vivo assessments. This technique enables the measurement of key carcass characteristics, including ribeye area (REA), subcutaneous fat thickness (SFT), and marbling score—typically assessed between the 12th and 13th ribs using real-time ultrasound. These traits, may be influenced by environmental factors such as birth year and month, sex, dam age at calving, and the animal's age. This study aimed to investigate the influence of environmental factors on ultrasound carcass traits using mixed factor analysis. The dataset included approximately 3,250 ultrasound records collected at weaning from male and female Nellore cattle raised on a farm in Bela Vista, MS, Brazil, between 2018 and 2022. Multivariate analysis was performed using the mixed factor analysis (MFA) method in the R statistical software, allowing for the exploration of interrelationships among multiple variables and graphical interpretation for decision-making. The average body weight was 194.7 kg; REA averaged 41.73 cm²; SFT was 2.63 mm; and the marbling score averaged 2.98. Principal component analysis (PCA) reduced 13 variables to five principal components, which explained 71.87% of the total variance. Component 1 was primarily associated with weight, age, REA, and SFT; component 2 was related to sex; and component 3 to birth year. Marbling and birth month were strongly associated with component 5, indicating potential seasonal effects. Graphical outputs revealed groupings among individuals based on multiple factors. While no clear separation was observed by sex or dam age, birth year, birth month, and calf age significantly influenced carcass traits. These findings highlight the importance of strategic management during the calving season and suggest promising potential for genetic selection. Editor: Universidade Federal da Grande Dourados Tipo: Trabalho de Conclusão de Curso 2025-07-03T00:00:00Z http://repositorio.ufgd.edu.br/jspui/handle/prefix/6776 Título: Utilização da casca do abacaxi (Ananas comosus) desidratada como amaciante para carne bovina Autor(es): Fachim, William Golfetto Primeiro Orientador: Fernandes, Alexandre Rodrigo Mendes Abstract: Beef quality, especially tenderness, has been increasingly under pressure from consumers. In this case, the use of natural and commercial tenderizers has been an alternative to improve the tenderness of meat cuts. The present study aimed to evaluate the efficiency of different meat tenderizers in relation to the fresh cut. A commercial tenderizer based on papain and two products obtained from drying pineapple peel by freeze-drying and in an oven were used on samples of sirloin (Longissimus dorsi), in relation to the parameters of pH, colorimetry, water retention capacity, cooking loss and shear force. The experiment was conducted at LAPAGRO/UFGD using four treatments with four replicates (steaks) each. From the pineapple peel, the experiment was conducted by drying in an oven (60°C/72h) and freeze drying (−40°C for 7 days). Data were analyzed by ANOVA and Tukey's test at 5% significance. The results indicated that there was no significant difference between treatments for pH, WHC and shear force. Cooking loss was significantly lower in treatments with softeners, specifically in the commercial softener. Colorimetry showed significant differences in components A* and B*, in the intensity of red and yellow, influenced by the color of the softeners applied. It was concluded that, although treatments with bromelain were not statistically significant compared to the control in relation to instrumental softness, they showed a positive trend in water retention and reduction of cooking loss, with emphasis on freeze-dried pineapple peel as a promising alternative for natural softener. Editor: Universidade Federal da Grande Dourados Tipo: Trabalho de Conclusão de Curso 2025-06-26T00:00:00Z