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91.
A total of 78 female and male Nero Siciliano pigs were used. Forty-one pigs were reared following the traditional management system, 37 pigs were reared in pens with a small outdoor paddock and fed to appetite using commercial rations according to the growing period. Both male and female pigs were castrated. All pigs were weighed and measured periodically. Body measurements included height at withers, chest girth, body length, width at shoulders and at rump. Age and body weight at slaughter ranged respectively from 371 to 572 days and from 79 to 113 kg. The carcasses were weighed and dissected into lean, fat and bone cuts. In the early and final stages indoor-pigs grew faster than those reared outdoors. Trends in body length were similar for the two rearing systems, for width at shoulders and rump, chest girth and height at withers, indoor pigs showed higher values than the outdoor ones. Carcasses of similar weight were longer in outdoor than in indoor pigs but the latter showed greater subcutaneous fat thickness. Outdoor pigs had the lowest dressing percentage and the highest percentage of lean cuts, such as shoulder and ham, but not of neck and loin. Sex did not significantly affect the analysed characteristics. 相似文献
92.
This article provides details of research work which aims to increase the range of applications in which membranes can be used by improving the epoxies used to form tube-sheets, making them more chemically and thermally stable, more resistant to organic solvents, and with improved mechanical properties. 相似文献
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94.
Carolina Griebeler Gianluca Tondi Thomas Schnabel Carmen Iglesias Sergio Ruiz 《Holz als Roh- und Werkstoff》2018,76(5):1495-1504
A new method that consists of combining wood pre-grading by surface colour followed by the application of homogeneity thermal treatments is proposed to reduce the surface colour variability of the thermally modified blue gum wood. To identify the conditions of the homogeneity thermal treatment for two pre-graded groups with different initial surface colours (pinkish and yellowish), the effects of applying 25 different thermal treatment intensities to such groups were analysed. The effects of this method on mass loss and volumetric swelling were also analysed. Results show that an optical pre-grading of the wood samples and treatments under different conditions can reduce the colour variability of the blue gum wood samples, as well as the volumetric swelling. Mass loss was not homogenised after the treatment, but the difference of masses between the two groups was similar to their untreated state. The application of this new methodology may be of interest for the sawn timber industry to bring more uniform boards on the markets and to promote Eucalyptus globulus as a price-competitive and sustainable alternative timber. 相似文献
95.
The use of bovine rumen protein (raw and extruded) as a replacement for extruded soy protein concentrate in three meat products (pork sausage, chicken hamburger, and kibbe) was investigated. Similarity between rumen and soy protein meat products was assessed using triangle tests and sensory acceptability evaluated by consumer panelists using a nine-point hedonic scale. The addition of raw rumen protein was detected in all meat product types tested, while extruded rumen protein was only detected in kibbe. The addition of raw rumen protein decreased the acceptability of pork sausage aroma and flavor, but improved kibbe appearance, texture and overall acceptability. The addition of extruded rumen protein reduced the acceptability of chicken hamburger texture, but improved pork sausage flavor. Replacement of soy protein by bovine rumen protein is feasible based upon sensory results, but depended upon its form and the type of meat product to which it was added. 相似文献
96.
Carolina Rojas-Garbanzo Ana M. PérezJairol Bustos-Carmona Fabrice Vaillant 《Food research international (Ottawa, Ont.)》2011,44(7):2377-2384
The identification and quantification of carotenoids has been carried out on tropical and non tropical fruits because of two important carotenoid's properties: as antioxidant compounds having a prevention role in some diseases, and as a source of provitamin A needed for a good human nutrition. This study aimed to identify carotenoids present during different steps for producing flour from Costa Rican peach-palm fruit (Bactris gasipaes H.B.K). Nine carotenoids were tentatively identified and quantified by HPLC-DAD in raw pulp, and 14 were detected in cooked pulp, the additional five being products of isomerization and hydroxylation of carotenoids in the raw pulp. The flour contained 13 carotenoids, one less (all-trans-??-criptoxanthin) than in cooked pulp, with the main one being all-trans ??-carotene. This carotenoid was also present in raw pulp at a concentration of 96.0 ± 1.7 ??g equiv. of ??-carotene g−1 dw. The concentration decreased significantly (P < 0.05) during cooking and drying to reach a final concentration of 33.3 ± 1.0 ??g equiv. ??-carotene g−1 dw in the flour. Flour production reduced (P < 0.05) the total carotenoid content from 373.4 to 237.7 ??g of ??-carotene g−1 dw, with a final retention rate of 63.7% by the end of the process. Moreover, 9 of the 14 carotenoids account for high levels of provitamin A, which, even so, had decreased from 2723 retinol equivalents (RE) 100 g−1 in raw pulp to 1614 RE 100 g−1 in cooked pulp and 1289 RE 100 g−1 in flour. Provitamin A level is still high when compared to other common provitamin A sources. Our study shows that while there is a change in the levels and profile of carotenoids during the peach-palm flour process, and a reduction of provitamin A value, peach-palm fruit is a great source of bioactive compounds. 相似文献
97.
98.
Nalda Romero Paz Robert Lilia Masson Jaime Ortiz Jacquelinne Pavez Carolina Garrido Mariela Foster Carmen Dobarganes 《Journal of the science of food and agriculture》2004,84(9):943-948
The high temperature antioxidant efficiency of α‐tocopherol, α‐tocotrienol and a mixture of both on hazelnut oil were evaluated. Crude hazelnut oil (HZO), crude hazelnut oil treated with alumina (THZO), as well as three samples of THZO to which 150 mg kg?1 of α‐tocopherol, 140 mg kg?1 of α‐tocotrienol or a mixture containing 70 mg kg?1 of α‐tocopherol and 70 mg kg?1 of α‐tocotrienol, were added and submitted to thermal treatment at 180°C for 18 h. The addition of tocols to THZO decreased the formation of polar compounds and increased its oxidative stability in all the systems studied. However, α‐tocopherol showed a higher antioxidant capacity than α‐tocotrienol at high temperature. In addition, α‐tocotrienol showed a more rapid degradation rate than α‐tocopherol under the conditions studied. Copyright © 2004 Society of Chemical Industry 相似文献
99.
Mary A. Jamieson Carolina Quintero Dana M. Blumenthal 《Journal of chemical ecology》2013,39(9):1204-1208
Global environmental change alters the supply of multiple limiting resources that regulate plant primary and secondary metabolism. Through modifications in resource availability, acquisition, and allocation, global change is likely to influence plant chemical defenses, and consequently species interactions that are mediated by these compounds. While many studies focus on individual global change factors, simultaneous changes in abiotic factors may interact to influence plant allelochemicals. In this study, we examined the individual and interactive effects of nitrogen enrichment and altered precipitation patterns on chemical defense compounds (iridoid glycosides) of an invasive plant, Linaria dalmatica. Plants were grown from seed in native mixed-grass prairie for 2 years. Nitrogen and water treatments were applied in each growing season over this period. Results indicate that soil water and nitrogen availability interact to shape plant chemical defense concentrations in L. dalmatica. Nitrogen addition decreased iridoid glycoside concentrations by approximately 25 % under reduced water availability, increased concentrations by 37 % in ambient water plots, and had no effect on these chemical defenses for plants growing under augmented water supply. Thus, results show differing patterns of allelochemical response to nitrogen enrichment, with respect to both the magnitude and direction of change, depending on water availability. Our study demonstrates the importance of examining multiple environmental factors in order to predict potential changes in plant chemical defenses with climate change. 相似文献
100.
Xudong Feng Darrell Alec Patterson Murat Balaban Emma Anna Carolina Emanuelsson 《Chemical Engineering Research and Design》2013
Optimal loading and operating conditions for a new, superior immobilization of amano lipase from Pseudomonas fluorescens on woolen cloth were determined. The optimal enzyme loading was 46.8 mg g dry cloth−1 with activity of 200 U. A batch reactor was used to characterize process conditions important to industrial application of the wool immobilized lipase. The optimal pH for immobilized lipase in tributyrin hydrolysis was 7, slightly lower than that of free lipase (pH 8). The optimal temperature for both free and immobilized lipase was 45 °C. The immobilized lipase was more stable to reuse than some other lipase immobilizations, maintaining 85% of its activity after 6 long term runs and 75.8% of the original activity after storage of 40 weeks at 4 °C. The thermal stability of lipase was improved by 2.4 times after immobilization. The thermal deactivation rate of immobilized lipase followed the Arrhenius law with Ed = 199 kJ mol−1. The Michaelis–Menten constant (Km) of the lipase increased from 1.63 mM to 4.48 mM after immobilization. The immobilized lipase was also successfully applied for tributyrin hydrolysis in a novel enzyme process intensification technology – the spinning cloth disc reactor (SCDR): conversion increased by around 13% under similar conditions compared to a conventional batch stirred tank reactor. The SCDR is therefore key to exploiting the advantages of the wool immobilized lipase developed in this work. 相似文献