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91.
Physicochemical and sensory characteristics were measured in veal and beef from the Portuguese Mertolenga breed having 3 quality labels as follows: Mertolenga-PDO beef and veal which apply to purebred animals and “Vitela Tradicional do Montado”-PGI veal which applies to crossbred animals. Measurements were made in longissimus lumborum muscle aged for 6 days. The temperature 3 h post-mortem (T3), cooking losses and Warner–Bratzler shear force (WBSF) reflected carcass weight (CW) differences between groups. The pigment content was influenced by age, with beef having higher values than veal. WBSF correlated negatively with intramuscular fat in Mertolenga-PDO beef, but not on veal. WBSF correlated positively with cooking losses and negatively with myofibrillar fragmentation index, tenderness, juiciness and overall acceptability. Cooking losses and juiciness were the main contributors for the tenderness differences. Vitela Tradicional do Montado-PGI and Mertolenga-PDO veal had lighter colour and were considered tender. The three meat types were well discriminated based on pHu, a* and C* parameters by canonical discriminant analysis.  相似文献   
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As a result of the economic crisis faced in Brazil, industries in the red ceramic sector have economic problems. The objective of this work was to evaluate, technologically and economically, through analysis of economy, the implementation of the production of ceramic tiles, a material with higher added value than bricks and ceramic blocks, in a ceramic industry located in the state of Rio de Janeiro, Brazil. The ceramic tiles were produced containing the incorporation of ornamental rock waste (ORW). The state has a region that has a red ceramic pole, but produces only products with lower added value. For this, specimens were produced with four different ceramic masses burned at temperatures in the range of 800 to 1050°C. Three masses were produced with different clays from the region (ceramic mass 1, 2 and 3) and a ceramic mass 4 was evaluated containing the clay that presented the best results and with the inclusion of sand and ORW, aiming at the analysis of economy. It was found that the masses containing only clays showed satisfactory parameters of resistance, but showed deficiencies in water absorption. The fourth mass, however, presented acceptable values in all the evaluated properties and was chosen to carry out a full-scale industrial test, which enabled the development of economic analysis and an economic analysis using the theory of real options. The results obtained in this last stage were also positive, providing an internal rate of return of 16.82%, above the minimum practiced rate of 15%, proving the efficiency of the economy applied to the manufacture of extruded tiles in the industries of the study region.  相似文献   
95.
The capability of Pleurotus ostreatus mushroom to accumulate lithium (Li) and the accessibility of this Li compared with lithium carbonate (Li2CO3), often used as psychiatric medicine, were investigated. Mushrooms were produced on a substrate-based on coffee husk, with different added concentrations of lithium chloride (LiCl). Biological efficiency (BE), the crude protein content, the concentration of Li and other elements present in mushrooms were determined. The sequential extraction and in vitro test were used to verify the accessibility and the degree of solubility of this element. Li concentration in mushrooms was directly influenced by increasing LiCl concentration in the substrate (P < 0.05). The BE was not affected by different concentrations of LiCl. Li present in enriched mushrooms showed greater accessibility than in Li2CO3. Therefore, P. ostreatus mushrooms, enriched with lithium can be an alternative source of Li, as well as being a food with high nutritional value.  相似文献   
96.
Blue polydiacetylene vesicles were studied with regard to their behaviour under variations in storage temperature, heating, potentiometric titration and in the presence of chemical components of milk, to evaluate their application as a sensor in the food industry. Vesicles were prepared using 10,12-pentacosadienoic acid (PCDA)/1,2-dimyristoyl-sn-glycero-3-phosphatidylcholine (DMPC). Their changes were monitored using UV-Vis absorption. Temperatures not exceeding 25°C did not cause colour change in PCDA/DMPC vesicles for a period of up to 60days of storage. Heating for 10min at 60 and 90°C, exposure to pH higher than 9.0 and the simulant solutions of the whey proteins, β-lactoglobulin and α-lactalbumin, promoted colour change from blue to red for the vesicles studied. The effects of routine factors on the characteristics and stability of polydiacetylene vesicles is important in defining the parameters related to their application as a sensor for the food industry.  相似文献   
97.
Color stability of swine blood was studied over 12 weeks of storage in plastic bags, after pH (7.40, 6.70, or 6.00) adjustment, saturation with carbon monoxide (CO) and spray-drying. CO-treated dried blood presented a redder color and higher reflectance between 610 and 700 nm, compared to a brownish-red color and lower reflectance of untreated samples. As indicated by reflectance spectra, blood pH adjustment did not influence (P > 0.05) the initial color of dried blood but influenced (P < 0.05) its color stability (browning index). During storage, CO-treated blood showed a reduction in reflectance percentages as well as in CIE L and a values, which was more pronounced in polyethylene (OTR = 4130 cm3/m2/day/atm) packaged samples. After 12 weeks of storage, CO-treated samples packaged in high OTR bags presented color indexes similar to those of the untreated dried samples. CO-treated samples packaged in nylon-polyethylene (OTR = 30–60 cm3/m2/day/atm) bags showed a smaller rate of discoloration and color difference (ΔE) between the CO-treated and untreated samples. Even with some darkening, packaging CO-treated dry blood in low OTR bags still gives an acceptable reddish color after 12 weeks of storage while untreated dry blood has a brownish color just after drying.  相似文献   
98.
BACKGROUND: L (+)‐Lactic acid is used in the pharmaceutical, textile and food industries as well as in the synthesis of biodegradable plastics. The aim of this study was to investigate the effects of different medium components added in cassava wastewater for the production of L (+)‐lactic acid by Lactobacillus rhamnosus B 103. RESULTS: The use of cassava wastewater (50 g L?1 of reducing sugar) with Tween 80 and corn steep liquor, at concentrations (v/v) of 1.27 mL L?1 and 65.4 mL L?1 respectively led to a lactic acid concentration of 41.65 g L?1 after 48 h of fermentation. The maximum lactic acid concentration produced in the reactor after 36 h of fermentation was 39.00 g L?1 using the same medium, but the pH was controlled by addition of 10 mol L?1 NaOH. CONCLUSION: The use of cassava wastewater for cultivation of L. rhamnosus is feasible, with a considerable production of lactic acid. Furthermore, it is an innovative proposal, as no references were found in the scientific literature on the use of this substrate for lactic acid production. Copyright © 2010 Society of Chemical Industry  相似文献   
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Scientometrics - Qualified human capital produces intellectual capital in institutions of higher education in the form of scientific articles and technological products, from the research...  相似文献   
100.
In the present study, 710 isolates of Aeromonas spp. have been collected from pig carcasses, diaphragm muscle, faeces, dehairing equipment and water in slaughterhouses at the North of Portugal. The isolates were obtained from a total of 154 samples. All presumptive Aeromonas isolates were subjected to ERIC-PCR analysis and those which presented a different pattern were taken and the species classified by gyrB gene sequencing. We have found the species A. hydrophila, A. salmonicida, A. bestiarum, A. caviae, A. media, A. veronii, A. allosaccharophila, A. simiae and A. aquariorum. To our knowledge, this extent of Aeromonas species diversity has not been previously described from meat or from the slaughter environment, perhaps due to the unreliability of available identification methods. A noticeable level of isolate redundancy (strains with identical gyrB sequence) from different samples collected in different dates was also obtained, indicating that only a few predominant strains of these species persist at the slaughter system. It is also important to emphasise the presence of Aeromonas species previously associated with illness in man.  相似文献   
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