Tratamentos Alternativos No Controle Da Antracnose E Sobre A Qualidade De Goiabas ‘pedro Sato’

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)One of the major problems in guava commercialization is the incidence of postharvest diseases, which coincides with fruit ripening. The effect of alternative products [potassium phosphite, calcium chloride, cassava starch, 1-methylcyclopropene (1-MCP), ethanol followed by sodium dichloro s. triazinetrione dehydrate (ethanol+chlorine)] and hydrothermal treatment, singly and in association, was evaluated on anthracnose control and on the physicochemical characteristics of ‘Pedro Sato’ guava. Treatments were applied to naturally infected guavas, in three maturity stages, which were stored at 22 or 25ºC for eight days. The incidence of anthracnose was evaluated by visual observation of symptoms and signs of the pathogens under an optical microscope, and the evaluated physicochemical parameters were skin color, pulp firmness, fresh mass loss, soluble solids, titratable acidity and ascorbic acid. The association of treatments ethanol+chlorine/cassava starch, hydrothermal treatment/cassava starch and ethanol+chlorine/1-MCP reduced the incidence of anthracnose in all three maturity stages in at least one storage period, leading to longer shelf life of fruits and a delay of two to four days in the onset of the disease. The maintenance of guava quality by means of treatment association was evidenced by delayed change in the skin color and less reduction in pulp firmness, especially for ethanol+chlorine/1-MCP. There was a positive correlation between the incidence of anthracnose and the maturity stage, expressed by the fruit skin color. The higher efficiency of treatment association in controlling anthracnose was directly related to the delay in fruit ripening, evidenced by the parameters skin color and pulp firmness. © 2016, Universidade Estadual Paulista (UNESP). All rights reserved.4243233392012/07207-7, FAPESP, Fundação de Amparo à Pesquisa do Estado de São PauloFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Application Of Artificial Intelligence Techniques For Temperature Prediction In A Polymerization Process

The main feature of the polymerization reaction is its complex nonlinear behaviour, which poses a challenging control system design for the batch reactor. The present work is concerned with the development of intelligent mathematical models to predict the styrene polymerization temperature. In order to improve the final product quality, these models will be used in predictive control schemes. Two techniques from the artificial intelligence field were used: Neuro-fuzzy and artificial neural networks. The pilot plant of styrene production consisted of: A stainless steel jacketed stirred reactor, a storage tank and a variable speed pump for the thermal fluid, temperature sensors (inside reactor, inlet and outlet of the jacket), a densimeter, and a PLC (Programmable Logic Controller). The temperature of the reactor is the process variable to be predicted using the historical data acquired from the pilot plant. Software MatLab 6.0 was used to implement neural and neuro-fuzzy models. The results showed that both models were able to predict online the reactor temperature profile successfully and that they were fast enough to be used in nonlinear predictive control strategies as well. © 2011, AIDIC Servizi S.r.l.24385390Buragohain, M., Mahanta, C., A novel approach for ANFIS modelling based on full factorial design (2008) Applied Soft Computing Journal, 8 (1), pp. 609-625. , DOI 10.1016/j.asoc.2007.03.010, PII S1568494607000464Cosenza, B., Galluzzo, M., Development of a predictive Type-2 neurofuzzy controller (2009) Chemical Engineering Transaction, 17, pp. 1203-1208Ghasem, N.M., Sata, S.A., Hussain, M.A., Temperature control of a bench-scale batch polymerization reactor for polystyrene production (2007) Chemical Engineering and Technology, 30 (9), pp. 1193-1202. , DOI 10.1002/ceat.200700165Lepore, R., Wouwer, A.V., Remy, M., Findeisen, R., Nagy, Z., Allgower, F., Optimization strategies for a MMA polymerization reactor (2007) Computers and Chemical Engineering, 31 (4), pp. 281-291. , DOI 10.1016/j.compchemeng.2006.07.005, PII S0098135406001967Pan, L., Yang, S.X., Analysing livestock farm odour using an adaptive neuro-fuzzy approach (2007) Biosystems Engineering, 97 (3), pp. 387-393. , DOI 10.1016/j.biosystemseng.2007.03.012, PII S1537511007000797Vasickaninova, A., Bakosova, M., Meszaros, A., Klemes, J., Neural network predictive control of a heat exchanger (2010) Chemical Engineering Transaction, 21, pp. 73-7

Design Of Automatic Control System For The Precipitation Of Bromelain From The Extract Of Pineapple Wastes [desenvolvimento De Sistema De Controle Para Precipitação De Bromelina A Partir De Resíduos De Abacaxi]

In this work, bromelain was recovered from ground pineapple stem and rind by means of precipitation with alcohol at low temperature. Bromelain is the name of a group of powerful protein-digesting, or proteolytic, enzymes that are particularly useful for reducing muscle and tissue inflammation and as a digestive aid. Temperature control is crucial to avoid irreversible protein denaturation and consequently to improve the quality of the enzyme recovered. The process was carried out alternatively in two fed-batch pilot tanks: a glass tank and a stainless steel tank. Aliquots containing 100 mL of pineapple aqueous extract were fed into the tank. Inside the jacketed tank, the protein was exposed to unsteady operating conditions during the addition of the precipitating agent (ethanol 99.5%) because the dilution ratio "aqueous extract to ethanol" and heat transfer area changed. The coolant flow rate was manipulated through a variable speed pump. Fine tuned conventional and adaptive PID controllers were on-line implemented using a fieldbus digital control system. The processing performance efficiency was enhanced and so was the quality (enzyme activity) of the product.30410331040Arakawa, T., Yoshiko, K., Timasheff, S., Protein precipitation and denaturation by dimethyl sulfoxide (2007) Biophysical Chemistry, 131 (1-3), pp. 62-70Backer, K.N., Rapid monitoring of recombinant protein products: A comparison of current technologies (2002) Trends In Biotechnology, 20 (4), pp. 149-156Bequette, B.W., Process control: Modelling, design, and simulation (2003) New Jersey: Prentice HallCesar, A.C., Silva, R., Lucarini, A.C., Pineapple stem and rind proteolytic enzymes recovery (In Portuguese) (1999) Revista De Iniciação Científca, 1, pp. 47-53Desai, M., Downstream Processing of Proteins: Methods and Protocols, pp. 1-10. , France: 2000, (Methods in Biotechnology, 9)Double, M., Kruthivent, A.K., (2007) Green, Chemistry and Engineering, p. 320. , India: Elsevier Science and TechnologyFiksdal, L., Tryland, I., Application of rapid enzyme assay techniques for monitoring of microbial water quality (2008) Environmental Biotechnology, 19, pp. 289-294Freiman, L.O., Sabaa Srur, A.U.O., Determination of total protein and aminoacid composition of bromelain extracted from pineapple plant residues (Ananás Comosus, (L.) Merril) (1999) Ciência E Tecnologia De Alimentos, 2, p. 19Gadkar, K.G., Mehra, S., Gomes, J., On-line adaptation of neural networks for bioprocess control (2005) Computers & Chemical Engineering, 29, pp. 1047-1057Hedhammar, M., Karlstron, A.E., Hober, S., (2006) Chromatographic Methods For Protein Purifcation, , Stockholm: Royal Institute of TechnologyHolwill, I., Rapid analysis of biosensor data using initial rate determination and its application to bioprocess monitoring (1996) Process Control and Quality, 8 (4), pp. 133-145Kim, W.-S., Hirasawa, I., Kim, W.-S., Aging characteristics of protein precipitates by polyelectrolyte precipitation in turbulently agitated reactor (2002) Chemical Engineering Science, 57, pp. 4077-4085Kim, W.-S., Hirasawa, I., Kim, W.-S., Effects of experimental conditions on the mechanism of particle aggregation in protein precipitation by polyelectrolytes with a high molecular weight (2001) Chemical Engineering Science, 56, pp. 6525-6534Locher, G., Sonnleitner, B., Fiechter, A., On-line measurement in biotechnology: Techniques (1992) Journal of Biotechnology, 25, pp. 23-5