Procedimiento de preparado de rodajas de berenjena frita con posterior congelación

Referencia OEPM: P9001681.-- Fecha de solicitud: 18/06/1990.-- Titular: Consejo Superior de Investigaciones Científicas (CSIC).El procedimiento de preparado de rodajas de berenjena frita con posterior congelación describe la obtención a partir de berenjena de un producto no perecedero mediante el tratamiento de fritura, congelación y conservación al estado congelado. Con la fritura se consigue evitar el pardeamiento enzimático. Este procedimiento es aplicable al mercado del producto vegetal al estado congelado y la utilización de un cocinado previo (fritura) del producto vegetal antes de su congelación.Peer reviewe

Actinidin in kiwifruit cultivars

Actinidin content was determined in four kiwifruit cultivars: Hayward, Abbot, Bruno and Monty, all grown in Spain. The flesh contains the highest actinidin activity, followed by the zones with seeds and core. Among the four cultivars assayed, Bruno and Hayward had the greatest activity of actinidin in the flesh (Zone A). The molecular weight determined by gel electrophoresis for actinidin was 28 kDa. Kiwifruit could be a good source of proteinases in countries which do not grow papaya and pineapple. © 1995 Springer-Verlag.The research reported here was supported by Consejo Superior de Investigaciones Científicas.Peer Reviewe

Peroxidase of Kiwifruit

Peroxidase from kiwifruit (Actinidia chinensis) was extracted, precipitated with ammonium sulfate, and purified by DEAE-cellulose chromatography. Only one band with peroxidase activity with an estimated molecular weight of 40,00–42,000 daltons was found by sodium do-decyl sulfate-polyacrylamide gel electrophoresis.This research was supported by CONACYT-México and Organización de los Estados Americanos.Peer reviewe

Protective effect of ascorbic acid against the browning developed in apple fruit treated with high hydrostatic pressure

Apple Reineta variety was used as an apple dessert. The 1-1.5-cm cubes were immersed in a sucrose solution (30% w/v) and subjected to high pressure (HP) of 400 MPa for 30 min at 5°C. Different ascorbic acid concentrations were used to protect the fruit from the browning developed after the HP treatment. After 2 months of storage at 5°C, no brown color was observed in the samples treated with 20 mM ascorbic acid, and they were acceptable to consumers. However, untreated samples presented fermentation, and they were not acceptable to consumers. The electric conductivity and potassium content were found to be good indicators of the metabolites released from the fruit to the solution in samples treated with high pressure. HP did not affect the peroxidase activity but eliminated the microbial population.Peer Reviewe

Effects of pressure processing on strawberry studied by nuclear magnetic resonance

Two different nuclear magnetic resonance techniques, namely magnetic resonance imaging and 1H-HR-MAS NMR spectroscopy, have been employed to study the extent of the damage caused by relatively low pressures (100-200 MPa) in strawberry. MRI maps showed important changes in the relaxation behavior of water molecules in pressurized samples. These differences increased with the pressure level applied. ADC values clearly showed the destruction of biological barriers and the loss of cell compartments produced by pressure. This induced major water redistribution in the tissues and; therefore, substantial changes in the interactions between water molecules and their environment. Relaxation times in T1 and T2 maps clearly depicted these pressure induced modifications. Moreover, NMR spectroscopy showed significant differences in the main sugars content in control and pressurized samples. Sucrose hydrolysis seems to be enhanced by the pressure treatment. Industrial relevance: The research data presented in this paper show a deep insight into the phenomena which take place during pressure processing in a soft plant tissue. The Nuclear Magnetic Resonance (NMR) techniques employed offered the opportunity of studying the whole product without any preparative manipulation which could mask the pressure effects. The results obtained should be useful to understand how and why pressure causes damage to vegetal tissues and, therefore, to design optimized high-pressure treatments which minimize this damage. © 2009 Elsevier Ltd. All rights reserved.This work has been supported by the “National Plan of Spanish I+D+I” of the Ministry of Education and Science (MEC) through the projects AGL2007-63314/ALI and CSD2007-00045 MALTA CONSOLIDER-INGENIO 2010.Peer Reviewe

Recubrimiento prebiótico a base de okara para fritos y precocinados

Solicitud de patente (concesión en curso).-- Referencia OEPM: P200401674.-- Fecha de presentación: 08/07/2004.-- Solicitantes: Consejo Superior de Investigaciones Científicas (CSIC), Universidad Complutense de Madrid (UCM).Recubrimiento prebiótico a base de okara para fritos y precocinados. El objeto de la invención es el empleo de la okara en la alimentación humana, para la realización de recubrimientos en fritos y prefritos congelados fundamentalmente por su alto contenido en fibra y proteína. La okara es el residuo que queda en la obtención de la bebida de soja (mal llamada leche de soja) y del tofu. Tiene un alto contenido de fibra (49%) y proteína (33%). Debido a su composición podría ser usado para enriquecer en fibra y proteínas algunos alimentos y como suplemento en la dieta humana. Tiene un sabor muy agradable (similar a almendras). Es un residuo bastante perecedero, por lo que se debe eliminar su alto contenido en agua, mediante técnicas de secado (60°C) o liofilizado, antes de su utilización.Peer reviewe

Biological response of rats fed with tofu treated with high hydrostatic pressure

Emerging technologies for food preservation have arisen in recent years, such as high-pressure (HP) hydrostatic treatment, and the biological response for this kind of food preservation is not well-known. Forty female rats (six weeks old) were used in the experiment to evaluate the biological effects of HP treatment of tofu. The animals were divided into groups that were fed with tofu (untreated), tofu treated with HP, and conventional food (as control) for 28 days. The glucose level, mineral content (calcium, potassium, zinc, and magnesium), shinbone maximum shear force, weight of the body, and weight of organs (heart, liver, spleen, and kidneys) were analyzed. The biological response for the rats was that significant differences were found in the calcium amount determined on the serum of the rats fed with untreated tofu and those fed with tofu treated with HP, and the calcium amount was lower on the rats fed with tofu treated with HP. Also, there were significant differences in the weight of the liver, and it was lower in the rats fed with tofu treated with HP. It was quite remarkable how the weight of the body and organs were smaller in the rats fed with tofu in comparison to the weight of the control rats. In the other components assayed no significant differences were found. HP produces a potential effect on tofu as it is observed in the rats response to the tofu treated with HP.Peer Reviewe

Variation of cherimoya (Annona cherimola) texture during storage, as determined with an Instron food testing instrument

Two varieties of cherimoya (known in U.S as custard apple) were harvested at the green-ripe stage and subsequently ripened under the following conditons: 5°C and 40% relative humidity (RH); 10°C and 85% RH; 20°C and 40% RH. Samples of the fruits were taken every 2 or 3 days and the following determinations were made: weight losses, specific weight, total soluble solids content (relating it with a taste panel) and texture measurements (compression, puncture, and shearing tests) by means of an Instron Food Testing Instrument. The deformation increased with the storage time and the temperature. In the puncture test the force required to break the skin decreased with the storage time down to limit value, which was maintained. The force distance curves obtained in the shearing test showed a decrease of the force during storage until ripeness was reached.Peer reviewe

High hydrostatic pressure effects on vegetable structure

Cryo-fracture scanning electron microscopy revealed the changes that cauliflower and spinach leaves undergo after treatment with high hydrostatic pressure. High pressure changed cell permeability and enabled movement of water and metabolites from inside to outside of the cell. The ultrastructure showed that parenchyma organization disappeared in spinach leaf and cavity formation occurred after treatment. However, cauliflower exhibited a firm structure with a soaked appearance and would be more suitable than spinach for high hydrostatic pressure treatment.The authors are grateful to The CSIC, project ALI94-07786-C02-01, Madrid, Spain, for financial support.Peer reviewe

Detection of peroxidase activity in two-dimensional gel electrophoresis

Two-dimensional gel electrophoresis is a well-known technique to detect proteins and identify them by mass spectrometry. Peroxidase activity is commonly revealed in different fields of investigation by adding a substrate to the enzyme in the sample, in the presence of hydrogen peroxide. From these two points, a useful procedure to detect this enzymatic activity on two-dimensional gels is described. The novelty and interest of this technique is that the electrophoresis developed combines a nondenaturing gel with running denaturing conditions, allowing peroxidase activity to remain after the whole process. Therefore, the isoelectric point and the molecular weight can be used to separate different isoforms of peroxidase on a two-dimensional gel. © Springer-Verlag 2005.s This research was carried out with financial support from the Commission of the European Communities, specific RTD program “Quality of life and management of living resources”, QLK1- CT- 2002- D2230 projectPeer Reviewe