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FT Raman and FTIR/FTFIR skeletal spectra of different TiO2 powders, of both synthetic and commercial origin, and of Sr, Ba, Co and Ni metatitanates are reported and discussed in relation to the predictions of factor group analyses. The ability of vibrational techniques to show the presence of brookite impurities in both anatase and rutile, and of rutile in anatase, as well as to give morphological and surface information is emphasized. The spectra of SrTiO3, BaTiO3, NiTiO3 and CoTiO3 are also discussed in relation to their different structures (pervoskite and ilmenite-type).

5 páginas, 9 tablas, A zonal lipid study of albacore before and after the cooking process was carried out. Lipid classes as well as their corresponding fatty acids were identified and quantified. Triglycerides (TG) were found to be the major components (78-92%), followed by phosphatidylcholine (1-4%) and free fatty acids (2-7 70 ). Due to cooking, a slight loss in TG was obtained, accompanied by variable increases in all the other lipid classes. The fatty acid qualitative composition was very similar in all the lipid classes, although big differences from a quantitative point of view were obtained. A very high level of polyunsaturated fatty acids was found in phosphatidylcholine (40-47%) while this was very low in free fatty acids (16-26%). During cooking no significant changes in the fatty acid composition of lipid classes were obtained., Financial support for the Research Project (PR 84-0043) provided by the Comision Asesora de Investigacion Cientifica y Tecnica

13 páginas, 1 tabla, 9 figuras, A semi-empirical model of precooking of albacore was developed. This model was used in a simulation program to predict the optimal (minimum) precooking times. The simulations showed close agreement with experimental results. Regression equations were also calculated relating the precooking times with the initial total fish weight and its initial temperature. These equations can easily be used in albacore canning factories without having to use a computer, This work was supported by a research grant from the Comision Asesora de Investigacion Cientifica y Tecnica (PR 84-0042, 43, Spain).

4 páginas, 4 tablas, 1 figura, [EN] The effects of cooking and sterilization at several temperatures on the free amino acids (FAA) content in albacore (Thunnus alalunga) muscle were studied during the processing of canned tuna. FAAs were derivatized witho-phtalaldehyde, separated on a C18 column by HPLC and detected by both fluorescence and ultra-violet detectors. After cooking the loss of FAAs was not significant. However, in the final product sterilized at 115 °C and 110 °C (throughout the whole process) there were significant losses with regard to the start material, but not at 118 °C (all temperatures leading to the same lethal F-value). The influence of the thermal process time at 115 °C was evaluated for 60 and 100 min. Significant losses were found between both canned products (≈25%) and between the raw fish and the final product (≈12% and ≈34%, process time 60 and 100 min, respectively). The determination of the content of FAA present in canned albacore may be a useful indication of the severity of the thermal processing., [DE] Die Wirkung des Kochens und Sterilisierens bei verschiedenen Temperaturen auf den Gehalt an freien Aminosäuren (FAA) im Thunfischmuskel (Thunnus alalunga) wurde während der Herstellung von Thunfischkonserven untersucht. Die freien Aminosäuren wurden mito-Phtalaldehyd derivatisiert, auf einer C-18-Kolonne mit HPLC abgetrennt und durch Fluorescenz und UV-Detektoren nachgewiesen. Nach dem Kochen war der Verlust an FAA nicht signifikant, jedoch in dem bei 110° und 115 °C sterilisierten Endprodukt ergaben sich signifikante Verluste bezogen auf das Ausgangsmaterial, aber nicht auf das bei 118 °C erhitzte; alle Erhitzungstemperaturen führen zu demselben letalen F-Wert. Der Zeiteinfluß der Erhitzung bei 115 °C wurde bei 60 und 100 min bewertet. Signifikante Verluste sind bei beiden Dosenkonserven aufgetreten (≈25%) und zwischen diesen und dem Rohfisch ( ≈12% und ≈34%) bei einer Erhitzungszeit von 60 und 100 min). Die Bestimmung des FAA-Gehalts in Thunfischkonserven kann für den Nachweis der Einwandfreiheit des thermischen Prozesses sehr nützlich sein., Commission Asesora de Investigacion Cientifica y Tecnica (PR 84-0043).

5 páginas, 4 figuras, 5 tablas, [EN] Thermal conductivity values of dried and raw albacore muscle were determined by means of a thermal conductivity probe. A microcalorimetric method and differential scanning calorimetry were used to obtain specific heat values of dried and raw muscle and of dried muscle, respectively, at several temperatures between 20 °C and 150 °C. Thermal diffusivity was calculated during precooking of headed and eviscerated albacore and during heat treatment of cylindrical cans filled with edible parts of precooked albacore. The experimental temperature curves were adjusted to those obtained from an analytical solution of the heat transmission equation assuming cylindrical geometry, conduction mechanism and constant thermal properties of the material. From experimental thermal conductivity, specific heat and density values, thermal diffusivity values of 1.43 x 10−7 m2/s with perpendicular heat flux to fibers and 1.65 x 10−7 m2/s with parallel heat flux were calculated for raw albacore. The values of apparent thermal diffusivity were found 1.51 x 10−7 m2/s and 1.29 x 10−7 m2/s during precooking and heat treatment of cans, respectively., [DE] Die Wärmeleifähigkeit von getrocknetem und frischem Thunfisch wurde durch eingehende Untersuchungen bestimmt. Hierfür wurde eine mikorcalorimetrische Methode sowie die Differentialabtast-Calorimetrie angewandt, um damit die Werte für die spezifische Wärme des getrockneten und des frischen Muskels bei Temperaturen zwischen 20 °C und 150 °C zu bestimmen. Die Wärmediffusion wurde während des Vorkochens des ausgeweideten Thunfisches (aber mit Kopt) und während der Erhitzung der in Dosen abgefüllten eßbaren Teile des vorgekochten Thunfisches berechnet. Die experimentell erhaltenen Temperaturkurven wurden mit dene aus der analytischen Lösung der Wärmeübertragungsgleichung erhaltenen (bei Annahme einer cylindrischen Geometrie), des Leitfähigkeitsmechanismus und den konstanten thermischen Eigenschaften des Materials abgestimmt. Aus den experimentell gefundenen Werten wurde eine Wärmediffusion von 1,65·10−7 m2/s bei parallelem Wärmefluß für rohen Thunfisch gemessen, während beim Vorkochen bzw. bei Erhitzung von Dosen diese Werte bei 1,51·10−7 m2/s bzw. 1,29·10−7 m2/s lagen., This work was supported by a research grant from the Comision Asesora de Invesfigacion Cientifica y Tecnica (PR 84-0042,43, Spain).

Background High consumption of fish carries a lower risk of cardiovascular disease as a consequence of dietary omega-3 long chain polyunsaturated fatty acid (n-3 PUFA; especially EPA and DHA) content. A controversy exists about the component/s responsible of these beneficial effects and, in consequence, which is the best proportion between both fatty acids. We sought to determine, in healthy Wistar rats, the proportions of EPA and DHA that would induce beneficial effects on biomarkers of oxidative stress, and cardiovascular disease risk. Methods Female Wistar rats were fed for 13 weeks with 5 different dietary supplements of oils; 3 derived from fish (EPA/DHA ratios of 1:1, 2:1, 1:2) plus soybean and linseed as controls. The activities of major antioxidant enzymes (SOD, CAT, GPX, and GR) were determined in erythrocytes and liver, and the ORAC test was used to determine the antioxidant capacity in plasma. Also measured were: C reactive protein (CRP), endothelial dysfunction (sVCAM and sICAM), prothrombotic activity (PAI-1), lipid profile (triglycerides, cholesterol, HDLc, LDLc, Apo-A1, and Apo-B100), glycated haemoglobin and lipid peroxidation (LDL-ox and MDA values). Results After three months of nutritional intervention, we observed statistically significant differences in the ApoB100/ApoA1 ratio, glycated haemoglobin, VCAM-1, SOD and GPx in erythrocytes, ORAC values and LDL-ox. Supplementation with fish oil derived omega-3 PUFA increased VCAM-1, LDL-ox and plasma antioxidant capacity (ORAC). Conversely, the ApoB100/ApoA1 ratio and percentage glycated haemoglobin decreased. Conclusions Our results showed that a diet of a 1:1 ratio of EPA/DHA improved many of the oxidative stress parameters (SOD and GPx in erythrocytes), plasma antioxidant capacity (ORAC) and cardiovascular risk factors (glycated haemoglobin) relative to the other diets., This investigation was supported, in part, by the Spanish Ministry of Science and Innovation (Grants AGL2009-12374-C03-01, -02 and -03).

Crystalline phases have been coprecipitated from Al/Cr mixed-nitrate aqueous solutions with ammonium carbonate. These phases have been characte rized as probably layered hydroxycarbonates with the likely composition (NH 4 ) 2 (Al,Cr) 6 (OH) 14 (CO 3 ) 3 ·H 2 O, using XRD, FTIR and TG–DTA analyses. The calcination of these materials gives rise to amorphous mixed oxides where Cr is partly in the hexavalent state, while further calcination at 1173 K gives rise to polyphasic materials. Samples with Al: Cr atom ratio between 5:1 and 1:1 give rise to four phase materials with three corundum-type phases and a spinel-type phase. All these phases contain both Al and Cr.