Juan Antonio Monsoriu Serra

Effect of partial sodium replacement on physicochemical parameters of smoked sea bass during storage

The objective of this work was to study the effect of partial sodium replacement by potassium and packaging conditions on the physicochemical properties of smoked sea bass during cold storage. Sea bass fillets were salted with 100% NaCl (Na samples) or with 50% NaCl–50% KCl (Na:K samples), smoked, packaged under three different conditions (air, vacuum and modified atmosphere) and stored at 4 °C for 42 days. Physicochemical parameters, color and texture were periodically determined in the raw material and in smoked samples during cold storage. The smoking process led to a reduction in moisture, pH and aw values, and an increase in water holding capacity, ash and mineral contents. Smoked fish exhibited significant differences in color and texture as compared to fresh fish. The type of packaging had an effect on the pH, water holding capacity and texture. Samples in air exhibited the highest pH values and water holding capacity in these samples gradually decreased during storage. Textural parameters decreased during storage in samples packaged in vacuum and modified atmosphere. The pH of Na samples was initially higher than in Na:K samples, and this difference remained over the rest of the study. The type of salt did not affect the texture or other physicochemical parameters.

Influence of the Presence of Skin on the Salting Kinetics of European Sea Bass

The objective of this work was to study the influence of the presence of skin, as well as the effect of size, thickness, initial weight and salting time on the dry salting kinetics of European sea bass, in order to characterise the salting process to obtain a lightly salted product. Fillets salted by the skin side showed lower salt gain and water and weight losses, which would indicate the barrier effect of skin on mass transfer. Processing time, contact area, initial weight and volume had significant effect on weight loss. Meanwhile, only processing time and initial weight were significant variables for water and NaCl weight changes, however thickness, contact area and volume were not significant due to the high effect of initial weight. However, it could be considered that thickness, contact area and volume had an indirect effect on mass transfer because initial weight was directly related to these variables. Salt diffusivity value in samples salted on the flesh side (7.54 × 10-11 m 2/s) was similar to that reported in other studies.

Evolution of Volatile Fraction and ATP Related Compounds During Storage of Desalted Cod (Gadus morhua)

The objective of this work was to study the evolution of the volatile fraction, and ATP and its breakdown products, in desalted cod thermally treated (water blanching, steam blanching and microwave heating), stored at 4 °C. All analyses were carried out at 0, 7, 14, 21, and 28 days of storage, as in the treated samples as in the control samples (desalted cod without thermal pre-treatment). The study of the volatile fraction revealed a similar behavior of the water blanched and steam blanched samples, by one hand, and of the control samples and those treated with microwave, on the other hand. This fact would imply a lower effectiveness of the microwave treatment on the preservation of the initial odor of desalted cod. The initial K1-values were lower in control and microwave samples than in water and steam blanched samples. However, the higher increase of K1-values throughout the storage in control and microwave samples would indicate a higher spoilage for these samples during the studied period. According to these results, the two blanching treatments were more effective than microwave heating in the preservation of desalted cod.

Smartphysics: el uso docente del Smartphone para el desarrollo de competencias transversales

En este trabajo proponemos introducir nuevas practicas de laboratorio de fisica, y modificar algunas existentes, con el objetivo principal de que nuestros estudiantes desarrollen algunas de las competencias transversales establecidas por la Universitat Politecnica de Valencia (UPV), tales como pensamiento critico, comprension e integracion, aplicacion pensamiento practico, aprendizaje permanente, comunicacion efectiva, y trabajo en equipo y liderazgo. El instrumento que vamos a utilizar para alcanzar este objetivo es el telefono movil inteligente (smartphone), que operara tanto como dispositivo de medida como de almacenamiento de datos. Creemos que el uso del telefono movil sera un elemento motivador para el alumno ya que estan acostumbrados a su uso y ademas tendran la oportunidad de conocer nuevas aplicaciones de este dispositivo.

Criterios de combinación de colores para la arquitectura en Salubra I: estudio de tonos

Resumen: Realizamos un nuevo estudio de las combinaciones de colores seleccionados por Le Corbusier en los ‘claviers’ para la empresa de papeles pintados Salubra en 1931, mediante su analisis en el espacio de color Natural Color System NCS, que permite comprender las variables perceptivas de los colores (tono, negrura y cromaticidad) y sus criterios de armonia. En este articulo discutimos las gamas tonales seleccionadas y aquellas que estan ausentes., e intentamos desentranar el orden subyacente en las combinaciones de colores mediante el estudio de las similitudes y contrastes de sus tonalidades en NCS. De manera grafica, se demuestran algunos principios de armonia como el recurso habitual de contrastar tonos frios con calidos, algo que difiere ligeramente del tradicional contraste de complementariedad. El trabajo completo ha sido publicado en Color Research and Application