Effect of edible quinoa protein-chitosan based films on refrigerated strawberry ( Fragaria 7 ananassa ) quality

Background: Strawberries are non-climacteric fruits with a low respiration rate, but are subject to serious fungal deterioration during postharvest handling. The edible coatings based on chitosan (CH), quinoa protein-chitosan (Q/CH) and quinoa protein-chitosan-sunflower oil (Q/CH/SO) may provide a solution to this problem. Thus, in this work CH, Q/CH and Q/CH/SO were elaborated and applied to fresh strawberries, and its effect on the strawberries shelf life during storage for 15 d was evaluated by mold and yeast count, fungal decay, carbon dioxide rate, physicochemical properties, and sensory evaluation. Results: On all analysis days, the strawberries coated with the film-forming CH, Q/CH and Q/CH/SO solutions presented a significant lower amount of mold and yeast growth than the uncoated strawberries. Coated strawberries with Q/CH/SO decreased the CO2 emission rate by 60% compared to the uncoated strawberries. The color of the strawberries was not influenced by the films. There was no significant difference between the different coating groups and the uncoated group in the physicochemical parameters. Sensory analysis showed that the coating application retained the total sensorial quality. Conclusions: Fresh strawberries coated with CH, Q/CH/SO and Q/CH edible films had longer shelf lives than uncoated fruits

The gluten-free diet: Testing alternative cereals tolerated by celiac patients

A strict gluten-free diet (GFD) is the only currently available therapeutic treatment for patients with celiac disease, an autoimmune disorder of the small intestine associated with a permanent intolerance to gluten proteins. The complete elimination of gluten proteins contained in cereals from the diet is the key to celiac disease management. However, this generates numerous social and economic repercussions due to the ubiquity of gluten in foods. The research presented in this review focuses on the current status of alternative cereals and pseudocereals and their derivatives obtained by natural selection, breeding programs and transgenic or enzymatic technology, potential tolerated by celiac people. Finally, we describe several strategies for detoxification of dietary gluten. These included enzymatic cleavage of gliadin fragment by Prolyl endopeptidases (PEPs) from different organisms, degradation of toxic peptides by germinating cereal enzymes and transamidation of cereal flours. This information can be used to search for and develop cereals with the baking and nutritional qualities of toxic cereals, but which do not exacerbate this condition. © 2013 by the authors; licensee MDPI, Basel, Switzerland.This work was supported by the Spanish Ministry of Economy and Competitiveness (AGL2010-19643-C02-02 and TRA2009_0047), the European Regional Development Fund (FEDER) and Junta de Andalucía (Project P09AGR-4783).Peer Reviewe

Artificial intelligence application for classification and selection of fish gelatin packaging film produced with incorporation of palm oil and plant essential oils

Supplementary material related to this article can be found, in the online version, at doi:https://doi.org/10.1016/j.fpsl.2020.100611.The k-Nearest Neighbor (KNN) algorithm was used to classify and select biodegradable packaging produced from fish gelatine incorporated with palm oil and clove and oregano essential oils. All reinforced films are highly resistant to attraction, with an emphasis on a sample of clove essential oil with a value of 53.18 MPa. Also, the addition of palm oil and essential oils increases the elasticity and thickness of the packages. The packages have antioxidant and antimicrobial properties with an inhibition zone for S. aureus of 11.73 and 11.23 mm for the film with essential oil of oregano and film with palm oil, respectively. KNN proved to be efficient for the classification and selection of packaging. The results highlighted the packaging with clove essential oil as the best for presenting the highest values of antioxidant activity, tensile strength, and elongation. Palm oil is an interesting alternative for applications in biodegradable films due to its antimicrobial activity, antioxidant properties, abundance, and low cost. Packaging made of fish gelatin with the addition of vegetable oils is a promising alternative for food applications.The authors thank the Coordination for the Improvement of Higher Education Personnel (CAPES) for the financial support.info:eu-repo/semantics/publishedVersio

Relación estructura-funcionalidad de glutelinas y aislados proteicos de amaranto (Amaranthus hypocondriacus)

Facultad de Ciencias Exacta

Estudio de estabilidad de pequeña perturbación del sistema eléctrico chileno considerando la política energética 2050

Memoria para optar al título de Ingeniero Civil EléctricoAnte los efectos nocivos que se proyectan debido al cambio climático, existe un interés global en impulsar políticas y tecnologías que permitan disminuir la huella de carbono. En el caso particular de los sistemas eléctricos de potencia (SEP), se han fijado metas a nivel global respecto a los niveles de generación basada en energías renovables no convencionales (ERNC). En este ámbito Chile se ha propuesto tener una generación basada en al menos un 70% por ERNC para el año 2050 [1]. En base al contexto anterior, es importante tener en cuenta los efectos que esta alta penetración de energías renovables puede tener en la red. Los principales son: reducción en la inercia sistémica y disminución de los niveles de cortocircuito del sistema. En adición, se debe considerar la topología longitudinal del sistema eléctrico nacional (SEN) que lo hace aún más propenso a problemas de estabilidad. En esta línea, el objetivo del trabajo consiste en desarrollar un análisis de pequeña perturbación del SEN para el año 2046, considerando una matriz con un 72% de ERNC y un 28% de generación sincrónica. Para dicha proyección se utilizó como base un escenario energético del informe del Ministerio de energía denominado Planificación Energética de Largo Plazo (PELP) [2]. Posteriormente, dicho escenario se modificó para adaptarlo a un caso de baja inercia y concentrada principalmente en el sur del SEN. En cuanto a la modelación propiamente tal, se utilizó el software DigSilent (PowerFactory), en particular se tomó como base el modelo de descarbonización desarrollado por el Coordinador eléctrico nacional (CEN) [3]. Los resultados obtenidos muestran que, con una gran adopción de energías renovables aún es posible obtener un sistema estable, al menos en una primera etapa de un análisis de estabilidad, como lo es un análisis de pequeña perturbación. Si bien aparecen modos electromecánicos mal amortiguados, estos son estables y es posible amortiguarlos. Por lo tanto, se puede asegurar la estabilidad en régimen permanente para pequeñas perturbaciones. El trabajo entrega una base para un posterior estudio dinámico sobre un sistema dominado por energías renovables y, puede ser extendido a partir de las líneas de trabajo presentadas en las conclusiones y trabajos futuros