A study on the rehydration ability of isolated apple cells after osmotic dehydration treatments

[EN] A study on rehydration of isolated apple cells is presented. Isolated cells previously dehydrated in 35% and 25% sucrose solutions were rehydrated in 5% sucrose under the microscope with the aim of analyzing the phenomena that take place during rehydration. Cells response to rehydration was found to be more heterogeneous than their response to hypertonic treatments. Cells showed different degrees of delay in their response, which was related to differences in the formation and preservation of membrane-to-wall connections. Results confirmed that rehydration success is based on the preservation of the structures along both, dehydration and rehydration treatments. During swelling, Hechtian strands are reincorporated to the protoplast as far as they are formed and preserved during dehydration and rehydration; their absence or shortage leading to a loss of rehydration capacity or even membrane lysis. Different stages have been identified during rehydration, mass transfer being coupled with deformation–relaxation phenomena once the protoplast reaches the cell wall. Phenomenological coefficients for water transfer indicated that rehydration kinetics is faster than water transfer during dehydration.The authors would like to acknowledge Ministerio de Educacion y Ciencia (Spain) for financial support (Project AGL2009-09905).Seguí Gil, L.; Fito Suñer, PJ.; Fito Maupoey, P. (2013). A study on the rehydration ability of isolated apple cells after osmotic dehydration treatments. Journal of Food Engineering. 115(2):145-153. https://doi.org/10.1016/j.jfoodeng.2012.08.038S145153115

EXTENSION OF THE PROJECT FOR OBTAINING BIOETHANOL FROM CITRUS WASTE

[EN] The production of citrus fruit in Spain generates more than 0.5 million tons of waste. This is mainly due to rejects when packing fresh fruit and the waste generated by processing industries. An important challenge for the citrus sector is the use of this waste to unlock its economic value and eliminate the environmental problems that it generates. The Instituto Universitario de Ingeniería de Alimentos para el Desarrollo (Iu-IAD) at the Universitat Politècnica de Valencia (UPV) has developed a system for transforming citrus waste into bioethanol and into high value-added products such as essential oils. The purpose of this study was to find the most appropriate sites to implement a bioethanol industry from citrus waste. A spreadsheet has been created to calculate the bioethanol mass flow from oranges, tangerines, lemons, and limes and grapefruits flow waste. Total waste of the main citrus producers was estimated as the sum of the rejects when packing fresh fruits and the waste generated by processing industries. Total waste value (oranges, tangerines, lemons and, limes and grapefruits) was multiplied by the ratio between mass flow and citrus waste flow in order to calculate the bioethanol production in different countries. The results suggest that Brazil, USA, Mexico, China, India and Italy would be the most appropriate countries to implement a bioethanol industry from citrus waste.Conesa Domínguez, C.; Fito Suñer, PJ.; Fito Maupoey, P. (2015). EXTENSION OF THE PROJECT FOR OBTAINING BIOETHANOL FROM CITRUS WASTE. Acta Horticulturae. (1065):1693-1702. doi:10.17660/ActaHortic.2015.1065.217S16931702106

Understanding osmotic dehydration of tissue structured foods by means of a cellular approach

[EN] This contribution presents a study on osmotic dehydration of tissue structured foods based on a microstructural approach in which simplified systems such as isolated apple cells and protoplasts have been used. An appropriate description of the microstructure of the raw material and its evolution during processing has been evidenced as critical in order to better understand and describe osmotic dehydration processes; as a direct consequence, it is stated that predictive models should incorporate this microstructural information so as to be more reliable. Microstructural changes observed by examining the isolated cells under the microscope along the treatments have been used to identify critical points that separate the stages that a cell undergoes, and which depend also on its particular response to the osmotic treatment (lysis, shrinkage or complete plasmolysis). Irreversible thermodynamics has been used to mathematically describe the process by distinguishing two main stages: one at which significant deformation-relaxation phenomena are coupled with mass transfer, and another one at which the former may be neglected. (C) 2011 Elsevier Ltd. All rights reserved.The authors would like to thank the Ministerio de Educacion y Ciencia (Spain) for financial support, and the organising committee of the International Conference on Food Innovation 2010 (FoodInnova2010) for granting this work with the best oral communication for young scientists award.Seguí Gil, L.; Fito Suñer, PJ.; Fito Maupoey, P. (2012). Understanding osmotic dehydration of tissue structured foods by means of a cellular approach. Journal of Food Engineering. 110(2):240-247. doi:10.1016/j.jfoodeng.2011.05.012S240247110

Study of the effect of microwave power coupled with hot air drying on orange peel by dielectric spectroscopy

[EN] Monitoring moisture and water activity during drying is crucial for process optimization, avoiding inadequate uses of energy. The main objective of this work was to study the dielectric properties of orange peel during hot air drying at 55 °C (HAD) and microwave power coupled with hot air drying at different power intensities (2 W/g, 4 W/g and 6 W/g). At 5, 15, 40, 60 and 120 min mass, aw, moisture, and permittivity were measured in fresh and dried samples. Results allowed developing a dielectric isotherm technique by adapting the GAB model to predict aw in dried orange peel by using ε'ε' (20 GHz). The physical meaning of the dielectric isotherm parameters (View the MathML sourceε0' and Cd) was studied. The value of View the MathML sourceε0' at 20 GHz (γ-dispersion) represents the induction effect of the minimum quantity of adsorbed water or the monomolecular moisture layer. The parameter Cd is related with isosteric heat, as well as the C parameter of the GAB model. The application of MW power produced an increase of isosteric heat or adsorption energy of the monomolecular layer, improving surface tension of samples and thus the hygroscopicity, explaining the reduction of the View the MathML sourceε0' independently of the quantity of the water molecules adsorbed.The authors would like to acknowledge the Basque Government for the financial support of the project (LasaiFood). The author Marta Castro-Giraldez wants to thanks to the UPV Postdoctoral Program (PAID-10-14) from Universidad Politecnica de Valencia for their support. The authors acknowledge the financial support from the Spanish Ministerio de Ciencia e Innovacion throughout the project AGL2011-30096.Talens Vila, C.; Castro Giraldez, M.; Fito Suñer, PJ. (2016). Study of the effect of microwave power coupled with hot air drying on orange peel by dielectric spectroscopy. LWT - Food Science and Technology. 66:622-628. https://doi.org/10.1016/j.lwt.2015.11.015S6226286

Effect of Microwave Power Coupled with Hot Air Drying on Sorption Isotherms and Microstructure of Orange Pee

[EN] Drying is one of the most cost-effective methods of worthwhile by-product valorisation. This study had two main objectives. The first was to determine the effect of hot air drying (HAD) combined with microwave (MW) irradiation on the treatment kinetics and the macrostructural and microstructural properties of the dried product. The second aim was to develop engineering tools to predict the extent of dehydration. Drying was performed using hot air at 55 A degrees C and the combined (HAD + MW) treatment at different power intensities (2, 4, and 6 W/g). After 5, 15, 40, 60, and 120 min, the mass, surface, volume, water activity and moisture were measured in fresh and dried samples. Sorption isotherms were obtained and fitted to the GAB model, with high correlation coefficients. The macroscopic and microscopic analyses showed shrinkage and swelling in the peel tissue caused by the MW treatment. The HAD + MW methods not only resulted in increased moisture reduction but also induced microstructural changes that generated higher sorption capacity.The authors would like to thank the Basque Government for the financial support of the project (LasaiFood). They also acknowledge the financial support from the Spanish Ministerio de Economia, Industria y Competitividad, Programa Estatal de I+D+i orientada a los Retos de la Sociedad AGL2016-80643-R. This paper is contribution no. 777 from AZTI (Food Research Division). The authors would like to thank the Electronic Microscopy Service of the Universidad Politecnica de Valencia for its assistance in the use of Cryo-SEM.Talens Vila, C.; Castro Giraldez, M.; Fito Suñer, PJ. (2018). Effect of Microwave Power Coupled with Hot Air Drying on Sorption Isotherms and Microstructure of Orange Pee. Food and Bioprocess Technology. 11(4):723-734. https://doi.org/10.1007/s11947-017-2041-xS723734114Al-Muhtaseb, A. H., McMinn, W. A. M., & Magee, T. R. A. (2002). Moisture sorption isotherm characteristics of food products: a review. Food and Bioproducts Processing, 80(2), 118–128. https://doi.org/10.1205/09603080252938753 .Andrade, R. D., Lemus, R., & Pérez, C. E. (2011). Models of sorption isotherms for food: uses and limitations. Vitae, 18(3), 325–334.Bejar, A. K., Ghanem, N., Mihoubi, D., Kechaou, N., & Mihoubi, N. B. (2011). Effect of infrared drying on drying kinetics, color, total phenols and water and oil holding capacities of orange (Citrus sinensis) peel and leaves. International Journal of Food Engineering, 7(5). https://doi.org/10.2202/1556-3758.2222 .Bergese, P. (2006). Specific heat, polarization and heat conduction in microwave heating systems: a nonequilibrium thermodynamic point of view. Acta Materialia, 54(7), 1843–1849. https://doi.org/10.1016/j.actamat.2005.11.042 .Castro-Giráldez, M., Fito, P. J., Chenoll, C., & Fito, P. (2010). Development of a dielectric spectroscopy technique for the determination of apple (Granny Smith) maturity. Innovative Food Science & Emerging Technologies, 11(4), 749–754. https://doi.org/10.1016/j.ifset.2010.08.002 .Castro-Giráldez, M., Fito, P. J., Dalla Rosa, M., & Fito, P. (2011a). Application of microwaves dielectric spectroscopy for controlling osmotic dehydration of kiwifruit (Actinidia deliciosa cv Hayward). Innovative Food Science & Emerging Technologies, 12(4), 623–627. https://doi.org/10.1016/j.ifset.2011.06.013 .Castro-Giráldez, M., Fito, P. J., & Fito, P. (2011b). Application of microwaves dielectric spectroscopy for controlling long time osmotic dehydration of parenchymatic apple tissue. Journal of Food Engineering, 104(2), 227–233. https://doi.org/10.1016/j.jfoodeng.2010.10.034 .Demirel, Y., & Sandler, S. I. (2001). Linear-nonequilibrium thermodynamics theory for coupled heat and mass transport. International Journal of Heat and Mass Transfer, 44(13), 2439–2451. https://doi.org/10.1016/S0017-9310(00)00291-X .Edrisi Sormoli, M., & Langrish, T. A. G. (2015). Moisture sorption isotherms and net isosteric heat of sorption for spray-dried pure orange juice powder. LWT—Food Science and Technology, 62(1, part 2), 875–882. https://doi.org/10.1016/j.lwt.2014.09.064 .Fava, F., Zanaroli, G., Vannini, L., Guerzoni, E., Bordoni, A., Viaggi, D., Robertson, J., Waldron, K., Bald, C., Esturo, A., Talens, C., Tueros, I., Cebrián, M., Sebők, A., Kuti, T., Broeze, J., Macias, M., & Brendle, H. G. (2013). New advances in the integrated management of food processing by-products in Europe: sustainable exploitation of fruit and cereal processing by-products with the production of new food products (NAMASTE EU). New Biotechnology, 30(6), 647–655. https://doi.org/10.1016/j.nbt.2013.05.001 .Fernández-López, J., Sendra-Nadal, E., Navarro, C., Sayas, E., Viuda-Martos, M., & Alvarez, J. A. P. (2009). Storage stability of a high dietary fibre powder from orange by-products. International Journal of Food Science and Technology, 44(4), 748–756. https://doi.org/10.1111/j.1365-2621.2008.01892.x .Ghanem, N., Mihoubi, D., Kechaou, N., & Mihoubi, N. B. (2012). Microwave dehydration of three citrus peel cultivars: effect on water and oil retention capacities, color, shrinkage and total phenols content. Industrial Crops and Products, 40, 167–177. https://doi.org/10.1016/j.indcrop.2012.03.009 .Gómez, A., López, R., Esturo, A., Bald, C., Tueros, I., Talens, C., & Raynaud, C. (2015). From waste products to raw materials for the development of new foods. Proceedings of the Institution of Civil Engineers: Waste and Resource Management, 168(2), 55–62. https://doi.org/10.1680/warm.13.00038 .Hossain, M. D., Bala, B. K., Hossain, M. A., & Mondol, M. R. A. (2001). Sorption isotherms and heat of sorption of pineapple. Journal of Food Engineering, 48(2), 103–107. https://doi.org/10.1016/s0260-8774(00)00132-1 .Igual, M., Contreras, C., & Martinez-Navarrete, N. (2010). Non-conventional techniques to obtain grapefruit jam. Innovative Food Science & Emerging Technologies, 11(2), 335–341. https://doi.org/10.1016/j.ifset.2010.01.009 .Kowalski, S. J., Rajewska, K., & Rybicki, A. (2005). Stresses generated during convective and microwave drying. Drying Technology, 23(9–11), 1875–1893. https://doi.org/10.1080/07373930500210226 .Labuza, T. P., & Altunakar, B. (2007). Water activity prediction and moisture sorption isotherms. In G. V. Barbosa-Cánovas, A. J. Fontana, S. J. Schmidt, & T. P. Labuza (Eds.), Water Activity in Foods: Fundamentals and Applications (Vol. 109–154). Iowa: IFT Press and Blackwell Publishing. https://doi.org/10.1002/9780470376454.ch5 .Larrauri, J. A. (1999). New approaches in the preparation of high dietary fibre powders from fruit by-products. Trends in Food Science & Technology, 10(1), 3–8. https://doi.org/10.1016/S0924-2244(99)00016-3 .Martín, M. E., Martínez-Navarrete, N., Chiralt, A., & Fito, P. (2003). Diseño y construcción de una instalación experimental para el estudio de la cinética de secado combinado por aire caliente y microondas. Alimentación Equipos y Tecnología, 22(181), 101–107.Quirijns, E. J., van Boxtel, A. J. B., van Loon, W. K. P., & van Straten, G. (2005). Sorption isotherms, GAB parameters and isosteric heat of sorption. Journal of the Science of Food and Agriculture, 85(11), 1805–1814. https://doi.org/10.1002/jsfa.2140 .Rizvi, S. S. H., & Benado, A. L. (1984). Thermodynamic properties of dehydrated foods. Food Technology, 38(3), 83–92.Robertson, J. A., de Monredon, F. D., Dysseler, P., Guillon, F., Amado, R., & Thibault, J.-F. (2000). Hydration properties of dietary fibre and resistant starch: a European collaborative study. Lebensmittel-Wissenschaft und -Technologie, 33(2), 72–79. https://doi.org/10.1006/fstl.1999.0595 .Schieber, A., Stintzing, F. C., & Carle, R. (2001). By-products of plant food processing as a source of functional compounds—recent developments. Trends in Food Science & Technology, 12(11), 401−+.Schiffmann, R. (2001). Microwave processes for the food industry. In A. Datta & R. Anantheswaran (Eds.), Handbook of microwave Technology for Food Applications (pp. 299–352). New York: Marcel Dekker.Talens, C., Castro-Giráldez, M., & Fito, P. J. (2016a). A thermodynamic model for hot-air microwave drying of orange peel. Journal of Food Engineering, 175, 33–42. https://doi.org/10.1016/j.jfoodeng.2015.12.001 .Talens, C., Castro-Giráldez, M., & Fito, P. J. (2016b). Study of the effect of microwave power coupled with hot air drying on orange peel by dielectric spectroscopy. LWT - Food Science and Technology, 66, 622–628. https://doi.org/10.1016/j.lwt.2015.11.015 .Talens, C., Arboleya, J. C., Castro-Giraldez, M., & Fito, P. J. (2017). Effect of microwave power coupled with hot air drying on process efficiency and physico-chemical properties of a new dietary fibre ingredient obtained from orange peel. LWT - Food Science and Technology, 77, 110–118. https://doi.org/10.1016/j.lwt.2016.11.036 .Traffano-Schiffo, M. V., Castro-Giráldez, M., Fito, P. J., & Balaguer, N. (2014). Thermodynamic model of meat drying by infrared thermography. Journal of Food Engineering, 128, 103–110. https://doi.org/10.1016/j.jfoodeng.2013.12.024 .Traffano-Schiffo, M. V., Castro-Giráldez, M., Colom, R. J., & Fito, P. J. (2015). Study of the application of dielectric spectroscopy to predict the water activity of meat during drying process. Journal of Food Engineering, 166, 285–290. https://doi.org/10.1016/j.jfoodeng.2015.06.030 .van den Berg, C., & Bruin, S. (1981). Water activity and its estimation in food systems—theoretical aspects. In L. B. Rockland & G. F. Stewart (Eds.), Water Activity: Influences on Food Quality (pp. 1–61). New York: Academic Press. https://doi.org/10.1016/B978-0-12-591350-8.50007-3 .Waldron, K. W. (2009). Part III exploitation of co-products as food and feed ingredients. In K. W. Waldron (Ed.), Handbook of waste management and co-product recovery in food processing (pp. 255–265). UK: Elsevier Science. https://doi.org/10.1533/9781845697051 .Yan, Z., Sousa-Gallagher, M. J., & Oliveira, F. A. R. (2008). Sorption isotherms and moisture sorption hysteresis of intermediate moisture content banana. Journal of Food Engineering, 86(3), 342–348. https://doi.org/10.1016/j.jfoodeng.2007.10.009

New technique of combined hot air and microwave drying to produce a new fiber ingredient from industrial by-products

[EN] The search for solutions to transform the by-products generated by the agri-food sector in high value-added ingredients is a priority. The aim of this research was to develop a microwave coupled with hot air drying technique allowing maximizing profits by reducing time and operational costs and to produce a dietary fiber ingredient with interesting technological properties for the development of healthy foods. The shrinkage-swelling phenomena occurred during drying changed the rehydration properties of the fibre ingredient obtained. An increase in particle size improved the fibre's swelling capacity when hydrated, allowing 50 % fat substitution in potato purees.Talens, C.; Castro Giráldez, M.; Fito Suñer, PJ. (2018). New technique of combined hot air and microwave drying to produce a new fiber ingredient from industrial by-products. En IDS 2018. 21st International Drying Symposium Proceedings. Editorial Universitat Politècnica de València. 49-56. https://doi.org/10.4995/IDS2018.2018.7875OCS495

Effect of microwave power coupled with hot air drying on process efficiency and physico-chemical properties of a new dietary fibre ingredient obtained from orange peel

[EN] Orange by-products are an excellent source of dietary fibre. The main objective of this work was to compare the physico-chemical and technological properties of fibres obtained from orange by-products by applying two different drying methods: hot air (HAD) and hot air coupled with microwave drying (HAD + MW). Process efficiency was also compared. 92% reduction in processing time and 77% reduction in energy consumption was achieved with HAD + MW. The drying treatment did not affect the physico-chemical properties of the fibres; however, the shrinkage-swelling phenomena that occurred during drying changed the rehydration properties of the fibre. HAD mainly affected the mechanical energy whereas HAD + MW affected the surface tension. An increase in particle size due to an increase in porosity during HAD + MW improved the fibre swelling capacity. HAD + MW can reduce drying time resulting in a more efficient drying process that positively affects the orange fibre's technological properties.The authors would like to acknowledge the Basque Government for the financial support of the project (LasaiFood). The author Marta Castro-Giraldez wants to thanks to the UPV Postdoctoral Program (PAID-10-14) from Universidad Politecnica de Valencia for their support. The authors acknowledge the financial support from the Spanish Ministerio de Economia, Industria y Competitividad, Programa Estatal de I + D + i orientada a los Retos de la Sociedad AGL2016-80643-R. This paper is contribution no 738 from AZTI (New Foods).Talens Vila, C.; Arboleya, JC.; Castro Giráldez, M.; Fito Suñer, PJ. (2017). Effect of microwave power coupled with hot air drying on process efficiency and physico-chemical properties of a new dietary fibre ingredient obtained from orange peel. LWT - Food Science and Technology. 77:110-118. https://doi.org/10.1016/j.lwt.2016.11.036S1101187

Encapsulation of lactase in Ca(II)-alginate beads: Effect of stabilizers and drying methods

[EN] The purpose of the present work was to analyze the effect of trehalose, arabic and guar gums on the preservation of beta-galactosidase activity in freeze-dried and vacuum dried Ca(II)-alginate beads. Freezing process was also studied as a first step of freeze-drying. Trehalose was critical for beta-galactosidase conservation, and guar gum as a second excipient showed the highest conservation effect (close to 95%). Systems with T-g values similar to 40 degrees C which were stables at ambient temperature were obtained, being trehalose the main responsible of the formation of an amorphous matrix. Vacuum dried beads showed smaller size (with Feret's diameter below 1.08 +/- 0.09 mm), higher circularity (reaching 0.78 +/- 0.06) and large cracks in their surface than freeze-dried beads, which were more spongy and voluminous. Ice crystallization of the beads revealed that the crystallization of Ca(II)-alginate system follows the Avrami kinetics of nucleation and growth. Particularly, Ca(II)-alginate showed an Avrami index of 2.03 +/- 0.07, which means that crystal growing is bidimensional. Neither the addition of trehalose nor gums affected the dimension of the ice growing or its rate. These results open an opportunity in the development of new lactic products able to be consumed by lactose intolerance people.This work was supported by Universidad de Buenos Aires (UBACyT 20020130100610BA), Agencia Nacional de Promoción Científica y Tecnológica (ANPCyT PICT 2013 0434 and 2013 1331), CIN-CONICET (PDTS 2015 n° 196). The author María Victoria Traffano Schiffo wants to thank Programa para la Formación de Personal Investigador (FPI) Pre-doctoral Program of the Universitat Politècnica de València (UPV) for support her PhD studies and also her mobility to Argentina.Traffano-Schiffo, MV.; Castro Giraldez, M.; Fito Suñer, PJ.; Santagapita, P. (2017). Encapsulation of lactase in Ca(II)-alginate beads: Effect of stabilizers and drying methods. Food Research International. 100(1):296-303. https://doi.org/10.1016/j.foodres.2017.07.020S296303100

Aplicación de la diferencia de temperatura media logarítmica a los intercambiadores de calor

En este artículo se explican las características básicas que hay que tener en cuenta a la hora de trabajar con transporte de calor en intercambiadores de calor, haciendo especial hincapié en el hecho de que la variación de temperatura a lo largo del recorrido de los tubos por los que viajan el fluido calefactor y el fluido refrigerante no es constante. Por ello, se recurre al concepto de la diferencia de temperatura media logarítmicaCastelló Gómez, ML.; Tarrazo Morell, J.; Fito Suñer, PJ. (2020). Aplicación de la diferencia de temperatura media logarítmica a los intercambiadores de calor. http://hdl.handle.net/10251/145778DE

Transporte de materia molecular en régimen estacionario en mezclas binarias

En este objeto de aprendizaje se detallan diferentes casos de transporte de materia en régimen estacionario en los que se aplica la ley de Fick. Concretamente, se trata la contradifusión molecular, la difusión de un componente cuando el resto permanecen en reposo y la difusión de dos componentes en el mismo sentido. Para entender mejor las ecuaciones, se incluyen ejemplos prácticas en cada caso.Castelló Gómez, ML.; Tarrazo Morell, J.; Fito Suñer, PJ. (2019). Transporte de materia molecular en régimen estacionario en mezclas binarias. http://hdl.handle.net/10251/122007DE