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31.
32.
Bignardi AB El Faro L Rosa GJ Cardoso VL Machado PF Albuquerque LG 《Journal of dairy science》2012,95(4):2157-2164
A total of 46,089 individual monthly test-day (TD) milk yields (10 test-days), from 7,331 complete first lactations of Holstein cattle were analyzed. A standard multivariate analysis (MV), reduced rank analyses fitting the first 2, 3, and 4 genetic principal components (PC2, PC3, PC4), and analyses that fitted a factor analytic structure considering 2, 3, and 4 factors (FAS2, FAS3, FAS4), were carried out. The models included the random animal genetic effect and fixed effects of the contemporary groups (herd-year-month of test-day), age of cow (linear and quadratic effects), and days in milk (linear effect). The residual covariance matrix was assumed to have full rank. Moreover, 2 random regression models were applied. Variance components were estimated by restricted maximum likelihood method. The heritability estimates ranged from 0.11 to 0.24. The genetic correlation estimates between TD obtained with the PC2 model were higher than those obtained with the MV model, especially on adjacent test-days at the end of lactation close to unity. The results indicate that for the data considered in this study, only 2 principal components are required to summarize the bulk of genetic variation among the 10 traits. 相似文献
33.
María V. Fernández Rosa J. Jagus Sandra L. Mugliaroli 《Food and Bioprocess Technology》2014,7(9):2528-2537
The effect of nisin alone and in combination with Microgard? on the natural microbial flora of ricotta cheese and in post-process contamination with Listeria innocua was studied. Microbial groups studied were mesophilic, psychrotrophic, proteolytic, lactic acid and coliform bacteria, and total molds and yeasts. Considering the evolution of all microbial groups and failure criteria adopted for mesophilic and coliform bacteria, this product reached the end of its shelf life before 5 days, which is insufficient time for product commercialization. The combined use of nisin and Microgard? proved to be more effective than the individual application on these microbial groups, resulting in a 13 days shelf life extension. Additionally, the combined treatment reduced the growth of L. innocua as a post-process contamination. 相似文献
34.
Virginia Glicerina Federica Balestra Marco Dalla Rosa Bjorn Bergenhstål Eva Tornberg Santina Romani 《Journal of food science》2014,79(7):E1359-E1365
The effect of different process stages on microstructural and visual properties of dark chocolate was studied. Samples were obtained at each phase of the manufacture process: mixing, prerefining, refining, conching, and tempering. A laser light diffraction technique and environmental scanning electron microscopy (ESEM) were used to study the particle size distribution (PSD) and to analyze modifications in the network structure. Moreover, colorimetric analyses (L*, h°, and C*) were performed on all samples. Each stage influenced in stronger way the microstructural characteristic of products and above all the PSD. Sauter diameter (D [3.2]) decreased from 5.44 μm of mixed chocolate sample to 3.83 μm, of the refined one. ESEM analysis also revealed wide variations in the network structure of samples during the process, with an increase of the aggregation and contact point between particles from mixing to refining stage. Samples obtained from the conching and tempering were characterized by small PS, and a less dense aggregate structure. From color results, samples with the finest particles, having larger specific surface area and the smallest diameter, appeared lighter and more saturated than those with coarse particles. 相似文献
35.
Emilio Alvarez-Parrilla Laura A. de la Rosa Ryszard Amarowicz Fereidoon Shahidi 《Food chemistry》2012
The potential of fresh and processed Jalapeño and Serrano pepper extracts for the control of lipid oxidation in several systems was investigated. The assays used included β-carotene/linoleate model system, striped corn oil, ground pork meat and Cu(II)-induced oxidation of human low-density lipoprotein (LDL). The results showed that all extracts were effective in at least one system, although their potency varied. Extracts of smoked Jalapeño were particularly effective. The lipid-protective effect of the extracts was mainly due to the presence of phenolic compounds, but other phytochemicals, such as chlorophylls were also involved. 相似文献
36.
A H2-based, denitrifying membrane-biofilm reactor (MBfR) was effective for removing trichloroethene (TCE) by reductive dechlorination. When TCE was first added to the MBfR, reductive dechlorination took place immediately and then increased over 18 weeks, and TCE was completely dechlorinated to ethene by about 120 days. These results indicate that TCE-dechlorinating bacteria were present naturally in the H2-based biofilm, and that enrichment for TCE-dechlorinating bacteria occurred. Dehalococcoides were documented in the MBfR biofilm before and after TCE feeding. Their proportion, quantified using the 16S rRNA gene, increased from 2.9 to 12% after TCE addition. This is the first report in which Dehalococcoides are proven to be present as part of an autotrophic biofilm community active in reductive dechlorination of TCE to ethene in a laboratory controlled experiment. Based on the complete reduction of TCE to ethene, the 16S rRNA clone libraries results, and the amount of tceA and bvcA, it appears that at least two Dehalococcoides strains were present in the enriched biofilm. One of them seems to be a new strain that is unique for having tceA and bvcA reductive dehalogenases. 相似文献
37.
T. Xu F.C. Cardoso A. Pineda E. Trevisi X. Shen F. Rosa J.S. Osorio J.J. Loor 《Journal of dairy science》2017,100(11):9153-9162
Long-term feeding of high-grain diets to dairy cows often results in systemic inflammation characterized by alterations in acute-phase proteins and other biomarkers, both in plasma and immune-responsive tissues like the liver. The molecular and systemic changes that characterize an acute grain feeding challenge remain unclear. The current study involved 6 Holstein and 6 Jersey cows in a replicated 2 × 2 Latin square. Periods (10 d) were divided into 4 stages (S): S1, d 1 to 3, served as baseline with total mixed ration (TMR) ad libitum; S2, d 4, served as restricted feeding, with cows offered 50% of the average daily intake observed in S1; S3, d 5, a grain challenge was performed, in which cows were fed a TMR ad libitum without (CON) or with an additional pellet wheat-barley (1:1; HIG) at 20% of dry matter intake top-dressed onto the TMR; S4, d 6 to 10, served as recovery during which cows were allowed ad libitum access to the TMR. Among the 28 biomarkers analyzed in blood 12 h after grain challenge on d 5, the concentrations of fatty acids and bilirubin increased in HIG Holstein but not Jersey cows. In Holsteins, feeding HIG also increased total protein and albumin while decreasing ceruloplasmin, myeloperoxidase, and alkaline phosphatase concentrations. At the molecular level, hepatic genes associated with inflammation (IL1B, IL6, TNF, TLR4, MYD88, and NFKB1) were upregulated in Holstein cows fed HIG versus CON. Despite such response, expression of the acute-phase proteins SAA and HP in Holsteins fed HIG compared with CON was markedly downregulated. In Holsteins fed HIG versus CON, the marked downregulation of SCD, ELOVL6, and MTTP along with upregulated CPT1A, ACOX1, and APOA5 indicated alterations in fatty acid and lipoprotein metabolism during grain challenge. Genes related to ketogenesis (HMGCS2 and ACAT1) were upregulated in Jerseys, and gluconeogenic genes (PDK4 and PCK1) were upregulated in Holstein cows fed HIG, suggesting alterations in ketone body and glucose production. Expression of phosphorylated p70S6K1, RPS6, and 4EBP1 proteins, as well as total mechanistic target of rapamycin (mTOR) protein, decreased in Holsteins fed HIG, whereas phosphorylated mTOR and 4EBP1 proteins increased in Jerseys fed HIG. From a metabolic and inflammatory biomarker standpoint, data indicate that Jersey cows better tolerated the acute grain challenge. Alterations in mTOR signaling proteins in both Jerseys and Holsteins fed HIG suggest a potential role for exogenous AA in the hepatic adaptations to grain challenge. It remains to be determined if these acute responses to a grain challenge can elicit long-term liver dysfunction, which could negatively affect welfare of the cow. 相似文献
38.
39.
Tiziano Tempesta Rosa Arboretti Giancristofaro Livio Corain Luigi Salmaso Diego Tomasi Vasco Boatto 《Food quality and preference》2010,21(7):827-836
This work’s aim is to evaluate the importance of landscape in wine quality perception using a novel integrated approach based on two statistical techniques, i.e. choice-based conjoint analysis (Gustafsson et al., 2001) and combination-based permutation tests (Corain and Salmaso, 2004, Pesarin and Salmaso, 2009a). To this end we developed a preference choice experiment which was submitted to a sample of respondents during blind wine tasting meetings. The obtained results allow us to weigh up and emphasise the importance of an attractive landscape to the perception of a finer quality of wine. Indeed, we noticed that associating wine to an image of greater visual impact, i.e. an evocative landscape, induces a significantly higher preference for the tasted wine. Moreover, the integrated application of choice-based conjoint analysis and combination-based permutation tests allows us to identify the specific relationship each market segment has with landscape, price and wine quality. 相似文献
40.
Carmen Cuadrado Gemma Ayet Luz Maria Robredo Javier Tabera Rosa Villa Mercedes M. Pedrosa Carmen Burbano Mercedes Muzquiz 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1996,203(3):268-271
The effects of natural fermentation upon phytic acid and less phosphorylated inositol phosphates ofLens culinaris var vulgaris cultivar Magda-20 were investigated. Seven fermentation runs were made following a 22 complete factorial design with three replicated centre points to study the effect of different conditions of temperature (28, 35 and 42°C) and broth concentration (79, 150 and 221 g/l). Samples were taken for each of them at daily intervals (0, 24, 48, 72 and 96 h). The pH value declined sharply in the first 24 h of fermentation, becoming stabilized from this time. The relation between lactic acid and titratable acidity presented important differences between the different fermentations, ranging from 30–80%. Phytic acid (IP
6), inositol pentakis (IP
5), tetrakis (IP
4) and tris-(IP
3) phosphates were quantitatively determined. The content of total inositol phosphates showed a maximum reduction of 63% at 72 h under the fermentation conditions of 42°C and 79 g/l. 相似文献