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11.
Ricardo I. Perez-Martin Jose M. Franco Santiago Aubourg Jose M. Gallardo 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1988,187(5):432-435
Summary 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.
Veränderung im Gehalt an freien Aminosäuren in Thunfischmuskel (Tunnus alalunga) während der Wärmebehandlung
Zusammenfassung 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.相似文献
12.
Fernando Corvillo Laura Gonzlez-Snchez Alberto Lpez-Lera Emilia Arjona Giovanni Ceccarini Ferruccio Santini David Araújo-Vilar Rebecca J Brown Joan Villarroya Francesc Villarroya Santiago Rodríguez de Crdoba Teresa Caballero Pilar Nozal Margarita Lpez-Trascasa 《International journal of molecular sciences》2021,22(12)
13.
Raffaele Sacchi Isabel Medina Santiago P. Aubourg Francesco Addeo Livio Paolillo 《Journal of the American Oil Chemists' Society》1993,70(3):225-228
Based on proton nuclear magnetic resonance (1H-NMR) spectroscopy, a rapid and structure-specific method for the determination of ω-3 polyunsaturated fatty acids (PUFAs)
in fish lipids is presented. The different chemical shift observed for the methyl resonance of ω-3 PUFAs (δ=0.95 ppm) with
respect to the methyl resonance of all other fatty acids (δ=0.86 ppm) has provided the possibility of proposing a new and
rapid method for the determination of ω-3 PUFA content. Twenty-four fish lipid samples (raw, cooked and canned albacore tuna)
produced results that showed good agreement between1H-NMR analysis and gas chromatographic determination. Raw and cooked samples showed significantly higher levels of ω-3 PUFA
than canned tuna. 相似文献
14.
Miguel Martínez-Espronceda Jesús D. Trigo Santiago Led H. Gilberto Barrón-González Javier Redondo Alfonso Baquero Luis Serrano 《Computer methods and programs in biomedicine》2014
Experiences applying standards in personal health devices (PHDs) show an inherent trade-off between interoperability and costs (in terms of processing load and development time). Therefore, reducing hardware and software costs as well as time-to-market is crucial for standards adoption. The ISO/IEEE11073 PHD family of standards (also referred to as X73PHD) provides interoperable communication between PHDs and aggregators. Nevertheless, the responsibility of achieving inexpensive implementations of X73PHD in limited resource microcontrollers falls directly on the developer. Hence, the authors previously presented a methodology based on patterns to implement X73-compliant PHDs into devices with low-voltage low-power constraints. That version was based on multitasking, which required additional features and resources. This paper therefore presents an event-driven evolution of the patterns-based methodology for cost-effective development of standardized PHDs. The results of comparing between the two versions showed that the mean values of decrease in memory consumption and cycles of latency are 11.59% and 45.95%, respectively. In addition, several enhancements in terms of cost-effectiveness and development time can be derived from the new version of the methodology. Therefore, the new approach could help in producing cost-effective X73-compliant PHDs, which in turn could foster the adoption of standards. 相似文献
15.
Santiago P. Aubourg Julia Vinagre Alicia Rodríguez Vanesa Losada M. Anglica Larraín Vilma Quitral Julio Gmez Liliana Maier Emma Wittig 《European Journal of Lipid Science and Technology》2005,107(6):411-417
Coho salmon (Oncorhynchus kisutch) is a fatty fish species whose farming production has greatly increased in recent years. Lipid damage produced during Coho salmon chilled storage was studied for up to 24 d. Lipid hydrolysis (free fatty acids, FFA) and oxidation (conjugated dienes; peroxide value, PV; thiobarbituric acid index, TBA‐i; fluorescent compounds formation, FR; browning development) were determined and compared to lipid composition (polyene index, PI; astaxanthin, AX) changes and sensory assessment (rancid odour development) results. Most lipid damage indices developed slowly during storage; thus, values obtained for FFA, PV, TBA‐i and FR were in all cases under 1.5 g/100 g, 4.0 meq oxygen/kg lipid, 0.40 mg malondialdehyde/kg muscle and 0.40, respectively. Odour assessment showed a significant (p <0.05) rancidity development at day 10, when compared to starting fish material; then, non‐acceptable values were obtained at days 19 and 24. The PI analysis showed not many differences during the storage time, with the lowest mean value at day 19. AX analysis indicated a relatively high content in the white muscle, which was maintained till the end of the experiment. A low oxidation development is concluded for Coho salmon lipids when compared to other fatty fish species under the same chilling conditions. AX was found to contribute to the oxidation stability of Coho salmon lipids, due to its free radical scavenger properties. 相似文献
16.
Modern MRI measurements deliver volumetric and time‐varying blood‐flow data of unprecedented quality. Visual analysis of these data potentially leads to a better diagnosis and risk assessment of various cardiovascular diseases. Recent advances have improved the speed and quality of the imaging data considerably. Nevertheless, the data remains compromised by noise and a lack of spatiotemporal resolution. Besides imaging data, also numerical simulations are employed. These are based on mathematical models of specific features of physical reality. However, these models require realistic parameters and boundary conditions based on measurements. We propose to use data assimilation to bring measured data and physically‐based simulation together, and to harness the mutual benefits. The accuracy and noise robustness of the coupled approach is validated using an analytic flow field. Furthermore, we present a comparative visualization that conveys the differences between using conventional interpolation and our coupled approach. 相似文献
17.
Vanesa Losada Jorge Barros‐Velzquez Jos M. Gallardo Santiago P. Aubourg 《European Journal of Lipid Science and Technology》2004,106(12):844-850
Slurry ice is a biphasic system consisting of small spherical ice crystals surrounded by seawater at subzero temperature. Its effect on lipid damage (hydrolysis and oxidation) was evaluated during the chilled storage of a fatty fish species, sardine (Sardina pilchardus). Slurry ice treatment was checked alone and in combination with ozone and compared to traditional flake icing during a 22‐day storage. Different lipid damage indices (free fatty acids, FFA; peroxide value, PV; thiobarbituric acid index, TBA‐i; fluorescent compounds, FR) were checked and compared to sensory assessment and nucleotide degradation (K value). According to lipid hydrolysis (FFA) and oxidation (PV and FR) developments, slurry ice showed an inhibitory effect (p <0.05) on lipid damage during storage, as well as an inhibition of nucleotide autolytic degradation. Ozonised slurry ice did not provide differences (p >0.05) from slurry ice alone when considering lipid hydrolysis, nucleotide degradation and some lipid oxidation indices (PV and FR), although a higher (p <0.05) TBA‐i was observed at day 22 of storage when compared to flake ice and slurry ice treatments. However, a lower (p <0.05) fluorescence development was observed for fish treated under ozonised slurry ice when compared to traditionally iced fish. Sensory assessment showed a higher shelf life for fish samples treated under ozonised slurry ice than for their counterparts under slurry ice (15 d versus 12 d), while flake icing led to a far shorter shelf life (5 d). According to sensory and biochemical (lipid matter and nucleotide) analysis, slurry ice has proved to be a promising technology for damage inhibition and quality retention in a fatty fish species such as sardine. Ozonised slurry ice was also shown to be useful, since a longer shelf life was obtained in the present experiment and a pro‐oxidant effect of ozone on sardine lipids was not proved. 相似文献
18.
A comparative study of the phospholipids of white muscle of six of the comercially utilized tuna species, including quantitative
analyses of phospholipid classes and studies of the acyl composition of the major components. Plasmalogen compounds also were
identified and quantified. Choline and ethanolamine glycerophospholipids were the most abundant classes in all the samples,
as well as the only molecules containing plasmalogens (16∶0, 18∶0, and 18∶1 alkenyl ether chains). The patterns of fatty acid
distribution within each of the phospholipid classes showed general similarities in the species analyzed. However, ratios
between certain saturated and polyunsaturated fatty acids in different phospholipid classes showed remarkable diffences. The
high content of n−3 polyunsaturated fatty acids in the principal phospholipids, such as the plasmalogens, and taking into
account the fatty acids possible importance in human nutrition, indicates that the white muscle of tuna species may be a potentially
important dietary item. 相似文献
19.
Software development is a fast-paced environment where developers need constant update to ever-changing technologies. Furthermore, process improvement initiatives have been proven useful in increasing the productivity of a software organization. As such, these organizations need to decide where to invest their training budget. As a result, training in technological update to their workforce or training in process conformance with its productive processes become conflicting alternatives. This paper presents a system dynamics simulation of a software factory product line. The objective of this simulation is to understand the changes in behavior when selecting either one of the above-training alternatives. The system dynamics model was validated with an expert panel, and the simulation results have been empirically validated—using statistical process control—against the performance baseline of a real software development organization. With the simulation under statistical control and performing like the baseline, the independent variables representing process conformance (process training) and technology skills (skills training) were modified to study their impact on product defects and process stability. Our results show that while both variables have positive impact on defects and process stability, investment in process training results in a process with less variation and with fewer defects. 相似文献
20.
The present study was designed to examine the effects of EFA deficiency (EFAD) on biochemical, functional, and structural
aspects of the kidney in growing and adult rats fed a normal or EFAD diet for 9 wk after weaning. Food and fluid intake (FI),
urine volume, and Na+ and K+ excretions were measured weekly from weeks 4 to 8 by placing the rats in individual metabolic cages for 24 h. At week 9,
Li+ and a 5% water load, respectively, were administered at 14 and 1.5 h prior to glomerular and proximal tubular function studies,
as assessed by 3-h creatinine (CCr) and Li+ (CLi+) clearances. Hematocrit and urine volume; serum and urine [Cr], [Li+], [Na+], and [K+]; and renal FA distribution were also measured. Data [corrected to 100 g/body weight (bw) and presented as means ±SEM] were
significant, at P<-0.05. Despite a similar ingestion of solids from weeks 4 to 7 (weeks 7 to 10 of life), the rats on the EFAD diet showed
a decreased body weight from week 5. From weeks 4 to 8, Fl and urine volume were similar for both groups, but the Fl increased
at week 6 in the EFAD group; 24-h Na+ and K+ excretions were similar at all weeks, except for an increase in the EFAD group for both ions at week 7. In the EFAD group,
CCr and CLi+ decreased by 27 and 56.3%, respectively (385.7±33.4 vs. 280±21.1, and 21.0±2.1 vs. 9.2±1.1 μL/min/100 g; n=9 vs. 10), the latter result suggesting increased proximal reabsorption. The 3-h Na+ and K+ excretions were similar, but the Li+ decreased (0.78±0.06×10−2 vs. 0.32±0.03×10−2 μeq/min/100 g) in the EFAD group, giving additional support to the suggestion. Renal structure was normal and similar for
both groups, but the EFAD group showed a more prominent proximal tubule brush border, together with heavier periodic acid-Schiff
staining in all specimens from weeks 5 to 9. In the EFAD group, FA of the n−9 and n−7 series were higher, but most of the
n−6 series were lower as a percentage of total lipids in the medulla and cortex. Medullary levels of 20∶4n−6 were maintained,
22∶4n−6 declined twice, arachidonic acid was maintained, and 20∶5n−3 was lower. The EFAD diet affected glomerular function,
proximal tubular structure and function, and FA distribution in the rat kidney. 相似文献