19 research outputs found

    Desarrollo sostenible en la producción agroalimentaria

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    PREF√ĀCIO: O desenvolvimento sustent√°vel √© considerado atualmente o paradigma dominante que guia o planejamento do desenvolvimento mundial e em particular, dos pa√≠ses latino-americanos. √Č um novo modelo de uso dos recursos naturais que n√£o compromete a disponibilidade destes elementos para as gera√ß√Ķes futuras, e al√©m disso inclui componentes econ√īmicos e sociais. Isso significa adotar um padr√£o de produ√ß√£o e consumo de modo a n√£o afetar o futuro da humanidade, combinando harmonicamente o desenvolvimento econ√īmico com a responsabilidade social e ambiental. A Associa√ß√£o de Universidades Grupo de Montevid√©u, tamb√©m conhecida pelo acr√īnimo AUGM, √© uma associa√ß√£o formada por universidades da Argentina, Bol√≠via, Brasil, Chile, Paraguai e Uruguai. Foi criada em 9 de agosto de 1991 com os objetivos de fortalecer e consolidar os recursos humanos, a pesquisa cient√≠fica e tecnol√≥gica, a forma√ß√£o cont√≠nua e a intera√ß√£o de seus membros com a sociedade. A AUGM possui treze comit√™s acad√™micos, entre eles o Comit√™ Agroalimentar, que foram concebidos para abordar, com enfoque multi interdisciplin√°rio, grandes configura√ß√Ķes tem√°ticas qualificadas como estrat√©gicas, por serem transversais e de car√°ter regional. Durante as XXVI Jornadas de Jovens Pesquisadores da AUGM, realizadas em 2018 em Mendoza, Argentina, discutiu-se dentro do Comit√™ Agroalimentar, a import√Ęncia e necessidade de se produzir uma publica√ß√£o envolvendo diferentes atores em prol do desenvolvimento sustent√°vel nos pa√≠ses da Associa√ß√£o. Na sequ√™ncia, tivemos muitas sugest√Ķes de temas e de autores, por diversos membros do Comit√™ Agroalimentar que estavam presentes na reuni√£o. Ap√≥s uma √°rdua sele√ß√£o, convidamos dezoito grupos de excel√™ncia para que redigissem seus cap√≠tulos em temas diversos e que se encontram reunidos nesta publica√ß√£o. O m√©rito e a responsabilidade de cada cap√≠tulo s√£o devidos aos autores, aos quais expressamos os nossos agradecimentos. Queremos ainda agradecer √†queles que atuaram como revisores dos cap√≠tulos, bem como a todas as Institui√ß√Ķes e aos colegas que acreditaram e apoiaram esta proposta. Por fim, esperamos que esta colet√Ęnea se transforme em uma ferramenta √ļtil de consulta √†queles que se interessam e se dedicam a estudos sobre o desenvolvimento sustent√°vel na produ√ß√£o agroalimentar

    Dynamic optimization of double-sided cooking of meat patties

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    10 p√°ginas, 6 tablas, 8 figurasOptimal operating procedures for double-sided cooking of frozen hamburger patties were computed using dynamic optimization techniques. The mathematical statement was to find the optimal control (e.g., heating surface temperature) over cooking time to minimize (or maximize) the performance index J, for example minimize cooking loss, and to ensure the required lethality and safe cooking temperature. The control vector parameterization framework was applied, and stochastic algorithm was used to locate the global optimum withreasonable computation effort (Integrated Controlled Random Searchfor Dynamic Systems). The performance index improved when the heating temperature profile was considered as control variable and when two control elements of variable size were used (compared withth e constant-temperature process or nominal case, DJ < 3%). When the lower bound was relaxed and two control elements were used, the performance index improved significantly (DJ < 7%). However, when the top and bottom plate temperatures were considered as two different controls, the plate temperature profiles obtained did not significantly improve the results compared with the nominal cases. When the temperature of the top and bottom plates and gap thickness were considered as control variables, and when two control elements of variable size for gap thickness were used, the performance index improved for long periods of cooking time (DJ < 2:5%).This research was supported partially by USDA NRI Grant # 9801542, NATO Grant # CRG-971581, and Consejo Nacional de Investigaciones Cient ńĪficas y T ecnicas (CONICET) de la Rep ublica Argentina.Peer reviewe

    Dynamic optimization of double-sided cooking of meat patties

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    10 p√°ginas, 6 tablas, 8 figurasOptimal operating procedures for double-sided cooking of frozen hamburger patties were computed using dynamic optimization techniques. The mathematical statement was to find the optimal control (e.g., heating surface temperature) over cooking time to minimize (or maximize) the performance index J, for example minimize cooking loss, and to ensure the required lethality and safe cooking temperature. The control vector parameterization framework was applied, and stochastic algorithm was used to locate the global optimum withreasonable computation effort (Integrated Controlled Random Searchfor Dynamic Systems). The performance index improved when the heating temperature profile was considered as control variable and when two control elements of variable size were used (compared withth e constant-temperature process or nominal case, DJ < 3%). When the lower bound was relaxed and two control elements were used, the performance index improved significantly (DJ < 7%). However, when the top and bottom plate temperatures were considered as two different controls, the plate temperature profiles obtained did not significantly improve the results compared with the nominal cases. When the temperature of the top and bottom plates and gap thickness were considered as control variables, and when two control elements of variable size for gap thickness were used, the performance index improved for long periods of cooking time (DJ < 2:5%).This research was supported partially by USDA NRI Grant # 9801542, NATO Grant # CRG-971581, and Consejo Nacional de Investigaciones Cient ńĪficas y T ecnicas (CONICET) de la Rep ublica Argentina.Peer reviewe

    Calcium-induced skim milk gels: Effect of milk powder concentration and pH on tribo-rheological characteristics and gel physico-chemical properties

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    The physico-chemical and tribo-rheological characteristics of calcium-induced skim milk gels obtained by heating of milk dispersions prepared with different concentrations of skim milk powder (10, 20 and 30% w/w) and calcium chloride (30, 60 and 90 mmol kg‚ąí1) were studied. The effect of pH on the gelation and on the final gel structure was also analyzed. For this purpose, the pH of selected samples was readjusted to the natural pH of milk of 6.66 after the calcium salt addition. The gelation process was analyzed by rheometry throughout temperature and time sweeps. Gelation at temperatures lower than 70 ¬įC was observed in samples with 10% w/w of skim milk powder (SM) and 30 mmol kg‚ąí1 of calcium chloride or similar ratio, when the amount of calcium remaining in the serum phase is enough to induce gel formation. The results obtained from temperature sweeps also suggest that the pH strongly affects the temperature at which gelation initiates. Structuring parameters confirmed these results. From time sweeps, it was observed that the kinetics of gelation depended on both composition and pH. Gels obtained using higher SM concentrations (20 and 30% w/w) showed better physical properties (low syneresis and high water holding capacity). Confocal laser microscopy images also showed a more homogeneous structure in those samples. Higher SM and calcium chloride concentrations improved the lubrication characteristics analyzed by tribology. Friction factors at 10 mm s‚ąí1 (typical speed in oral processing) decreased as the SM concentration increased. It is concluded that calcium-induced skim milk gels with different microstructure can be obtained by varying the concentration of skim milk powder and calcium salt added, and pH adjustment.EEA RafaelaFil: Olivares, Mar√≠a Laura. Consejo Nacional de Investigaciones Cient√≠ficas y T√©cnicas. Centro Cient√≠fico Tecnol√≥gico Conicet - Santa Fe. Instituto de Desarrollo Tecnol√≥gico para la Industria Qu√≠mica, ArgentinaFil: Olivares, Mar√≠a Laura. Universidad Nacional del Litoral. Facultad de Ingenier√≠a Qu√≠mica. Instituto de Desarrollo Tecnol√≥gico para la Industria Qu√≠mica; ArgentinaFil: Costabel, Luciana Maria. Instituto Nacional de Tecnolog√≠a Agropecuaria (INTA). Estaci√≥n Experimental Agropecuaria Rafaela. Instituto de Investigaci√≥n de la Cadena L√°ctea; ArgentinaFil: Costabel, Luciana Maria. Consejo Nacional de Investigaciones Cient√≠ficas y T√©cnicas. Instituto de Investigaci√≥n de la Cadena L√°ctea; ArgentinaFil: Zorrilla, Susana E. Consejo Nacional de Investigaciones Cient√≠ficas y T√©cnicas. Centro Cient√≠fico Tecnol√≥gico Conicet - Santa Fe. Instituto de Desarrollo Tecnol√≥gico para la Industria Qu√≠mica; ArgentinaFil: Zorrilla, Susana E. Universidad Nacional del Litoral. Facultad de Ingenier√≠a Qu√≠mica. Instituto de Desarrollo Tecnol√≥gico para la Industria Qu√≠mica; ArgentinaFil: Vicente, J. de University of Granada. Faculty of Sciences. Department of Applied Physics and Excellence Research Unit ‚ÄúModeling Nature‚ÄĚ (MNat); Espa√Ī

    Milk fortified with calcium: Changes in the physicochemical and rheological characteristics that affect the stability

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    The objective of this work was to analyze the changes in the physicochemical and rheological characteristics of milk fortified with different calcium salts. Reconstituted milk samples using skim milk powder with different concentrations of calcium chloride and calcium lactate (0, 5 and 30 mmol kg‚ąí1) were obtained. Several physicochemical and rheometric techniques were used to analyze the effect of milk fortification. According to the results, all the applied techniques indicated that some of the added calcium migrates into the casein micelle forming colloidal calcium phosphate, and that the calcium added as lactate enters the micelles to a greater extent. A part of whey proteins would also be integrated into the micellar structure. An addition of 5 mmol kg‚ąí1 of calcium chloride and calcium lactate would be practically feasible, due to the mineral balance and the thermal stability that were not significantly affected at that concentration level. In conclusion, the results obtained with physicochemical techniques commonly used in literature are in agreement with those obtained in this study by rheometry, demonstrating that this simple and rapid technique allows inferring about the changes in mineral balance and effects on thermal stability when different salts are used for milk fortification.EEA RafaelaFil: Acosta, Nadia Belen. Instituto Nacional de Tecnolog√≠a Agropecuaria (INTA). Estaci√≥n Experimental Agropecuaria Rafaela; ArgentinaFil: Sihufe, Guillermo Adri√°n. Consejo Nacional de Investigaciones Cient√≠ficas y T√©cnicas. Centro Cient√≠fico Tecnol√≥gico Conicet - Santa Fe. Instituto de Desarrollo Tecnol√≥gico para la Industria Qu√≠mica. Universidad Nacional del Litoral. Facultad de Ingenier√≠a Qu√≠mica. Instituto de Desarrollo Tecnol√≥gico para la Industria Qu√≠mica; ArgentinaFil: Meza, B√°rbara Erica. Consejo Nacional de Investigaciones Cient√≠ficas y T√©cnicas. Centro Cient√≠fico Tecnol√≥gico Conicet - Santa Fe. Instituto de Desarrollo Tecnol√≥gico para la Industria Qu√≠mica. Universidad Nacional del Litoral. Facultad de Ingenier√≠a Qu√≠mica. Instituto de Desarrollo Tecnol√≥gico para la Industria Qu√≠mica; ArgentinaFil: Marino, Fernanda. Consejo Nacional de Investigaciones Cient√≠ficas y T√©cnicas. Centro Cient√≠fico Tecnol√≥gico Conicet - Santa Fe. Instituto de Desarrollo Tecnol√≥gico para la Industria Qu√≠mica. Universidad Nacional del Litoral. Facultad de Ingenier√≠a Qu√≠mica. Instituto de Desarrollo Tecnol√≥gico para la Industria Qu√≠mica; ArgentinaFil: Costabel, Luciana Maria. Instituto Nacional de Tecnolog√≠a Agropecuaria (INTA). Estaci√≥n Experimental Agropecuaria Rafaela; ArgentinaFil: Zorrilla, Susana E. Consejo Nacional de Investigaciones Cient√≠ficas y T√©cnicas. Centro Cient√≠fico Tecnol√≥gico Conicet - Santa Fe. Instituto de Desarrollo Tecnol√≥gico para la Industria Qu√≠mica. Universidad Nacional del Litoral. Facultad de Ingenier√≠a Qu√≠mica. Instituto de Desarrollo Tecnol√≥gico para la Industria Qu√≠mica; ArgentinaFil: Olivares, Mar√≠a Laura. Consejo Nacional de Investigaciones Cient√≠ficas y T√©cnicas. Centro Cient√≠fico Tecnol√≥gico Conicet - Santa Fe. Instituto de Desarrollo Tecnol√≥gico para la Industria Qu√≠mica. Universidad Nacional del Litoral. Facultad de Ingenier√≠a Qu√≠mica. Instituto de Desarrollo Tecnol√≥gico para la Industria Qu√≠mica; Argentin

    Numerical modelling of the food freezing process in a quasi-hydrofluidisation system

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    The paper presents a study of food freezing using hydrofluidisation method, characterised by very high heat transfer coefficients exceeding 2500 W ¬∑ m‚ąí2 K‚ąí1, which constitutes a novel and promising technology. A numerical analysis of a system with a stationary group of food products was performed. This study aimed to investigate the geometrical parameters governing the freezing process, i.e., the position of food products above the orifices (from 50 mm to 70 mm), their mutual position, the diameter of orifices (3 mm or 5 mm), and the spacing of the orifices in an array (from 8 mm to 12 mm). In this method, the freezing time was from 3 min for 10 mm spherical food sample in moderate refrigerating medium temperatures up to 12 min for 30 mm spherical sample. Moreover, the freezing times at different liquid temperatures were compared in the range of ‚ąí20 ¬įC to ‚ąí5 ¬įC. Reducing the temperature by 5 K may lead to shortening the process by up to 50%. The hydrofluidisation method was assessed versus the immersion freezing for spherical products of different sizes showing the reduction of the process time from about 35% to over 60%.Fil: Stebel, M. Silesian University Of Technology; PoloniaFil: Smolka, Jochen. Silesian University Of Technology; PoloniaFil: Palacz, M. Silesian University Of Technology; PoloniaFil: Piechnik, E. Silesian University Of Technology; PoloniaFil: Puchalski, Cecilia Mabel. Silesian University Of Technology; PoloniaFil: Knap, M,. Silesian University Of Technology; PoloniaFil: Felissia, Fernando Esteban. Silesian University Of Technology; PoloniaFil: Eikevik, Tm. Norges Teknisk-naturvitenskapelige Universitet; NoruegaFil: Tolstorebrov, I. Norges Teknisk-naturvitenskapelige Universitet; NoruegaFil: Peralta, Juan Manuel. Consejo Nacional de Investigaciones Cient√≠ficas y T√©cnicas. Centro Cient√≠fico Tecnol√≥gico Conicet - Santa Fe. Instituto de Desarrollo Tecnol√≥gico para la Industria Qu√≠mica. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnol√≥gico para la Industria Qu√≠mica; ArgentinaFil: Zorrilla, Susana. Consejo Nacional de Investigaciones Cient√≠ficas y T√©cnicas. Centro Cient√≠fico Tecnol√≥gico Conicet - Santa Fe. Instituto de Desarrollo Tecnol√≥gico para la Industria Qu√≠mica. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnol√≥gico para la Industria Qu√≠mica; Argentin

    Prognostic and Predictive Biomarkers in Patients with Locally Advanced Rectal Cancer (LARC) Treated with Preoperative Chemoradiotherapy

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    Neoadjuvant chemoradiotherapy (CRT) is one of the standards of care in locally advanced rectal cancer (LARC). This retrospective study examines clinical, analytical, and pathological parameters collected from 77 patients with locally advanced (cT3-4 or cN+) rectal carcinoma diagnosed between 2007 and 2017 at our institution that were treated with preoperative CRT and surgery. In the prognosis analysis, lower hemoglobin levels (p = 0.008), lower lymphocyte/monocyte ratio (LMR) (p = 0.011), and higher platelet/lymphocyte ratio (PLR) (p = 0.029) in the second determination (Hb2, LMR2 and PLR2) were associated with the relapse group. The number of positive nodes after surgery (N+) showed a statistically significant association with relapse (p = 0.012). KRAS mutations were associated with a worse prognosis for 5 years progression-free and overall survival (p = 0.005 and 0.022; respectively). We propose a prognostic model based on four parameters (number of positive lymph nodes after surgery, hemoglobin levels, LMR, and PLR after neoadjuvant therapy) that can be a useful tool to estimate relapse risk. Moreover, bilirubin could be a useful parameter to predict the response to neoadjuvant CRT
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