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991.
Marion P. Costa Maria Lucia G. Monteiro Beatriz S. Frasao Vitor L.M. Silva Bruna L. Rodrigues Claudete C.J. Chiappini Carlos A. Conte-Junior 《Journal of dairy science》2017,100(1):157-168
Although the demand for goat milk products has been growing, they have lower consumer acceptability than products derived from cow milk. However, the addition of cupuassu pulp can be used to improve the formulation of these products. For this reason, the aim of this study was to investigate the influence of new goat milk yogurt manufactured with cupuassu pulp on physicochemical properties, consumers’ perceptions, and overall consumer acceptance. In addition, the effect of antioxidant health information on consumer acceptance and purchase intention of cupuassu goat milk yogurts was evaluated. The results demonstrated a positive expectation regarding linking and familiarity to goat milk products and products with cupuassu pulp. The pH, total phenolic content, lightness, redness, yellowness, and apparent viscosity were potentially affected by the addition of cupuassu, with the highest concentration of cupuassu (10%) exhibiting the greatest changes in parameters. Based on principal component analysis, partial least squares regression, and just-about-right and penalty analysis, the addition of cupuassu pulp improved some sensory attributes of goat milk yogurt, such as cupuassu aroma, cupuassu flavor, yellow color, consistency, and viscosity, which positively influenced product acceptance. In addition, antioxidant health information increased the acceptance and purchase intention of cupuassu goat milk yogurts. Taking into account the parameters investigated in this study, the best scoring formulation was goat milk yogurt with 10% cupuassu pulp. Our results suggest that cupuassu pulp can be considered a potential ingredient to improve the sensory and texture properties of goat milk yogurt. Furthermore, the antioxidant health information could be a sensory strategy to increase the acceptance of cupuassu goat milk yogurts. 相似文献
992.
Yoshimi Sato Nilo Bazzoli Elizete Rizzo Maria Beatriz Boschi Mario O. T. Miranda 《河流研究与利用》2005,21(8):939-950
The curimatã‐pacu Prochilodus argenteus is an important characiform from the São Francisco River basin that performs long‐distance migrations for spawning upstream during the rainy season, when the temperature and photoperiod are elevated. Despite the interruption of the migratory routes by the Três Marias Dam and accentuated decline in fishing, the curimatã‐pacu still sustains the fisheries at the Três Marias region in recent decades. The objective of this study was to evaluate the reproductive activity of P. argenteus in two sections of the São Francisco River, downstream from the Três Marias Dam, during the rainy season. In the first 34 km of the river, immediately below the dam, most of the females were in gonadal resting. At 34–54 km downstream from the dam, following the confluence with a medium‐sized tributary, the Abaeté River, there was a high frequency of males and females in reproductive activity. Follicular atresia was more frequent in the upper section of the river while postovulatory follicles occurred predominantly in the lower section. Fulton's condition factor and gonadosomatic index indicated that the females were in a better physiological and reproductive condition below the confluence with the Abaeté River. In contrast to the females, the males were less affected by damming, and testicular maturation was largely achieved in two river sections. Thus, although the section of the São Francisco River immediately below the Três Marias Dam was found to be unfavourable for the reproduction of the migratory fishes due principally to the hypolimnetic water from the reservoir, reproductive success of P. argenteus was achieved below the Abaeté River. In this section, the species encountered appropriate conditions for maturation and spawning, i.e. warm temperatures above 24°C, high water flow and dissolved oxygen, and low water transparency. These results indicate the importance of a non‐regulated tributary to minimize the ecological impact of a dam on the downstream native fish communities. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
993.
Beatriz Rodríguez Galdón Rafael Oropeza González Elena Rodríguez Rodríguez Carlos Díaz Romero 《Journal of the science of food and agriculture》2008,88(9):1554-1561
BACKGROUND: P, Na, K, Ca, Mg, Fe, Cu, Zn, Mn and Se were determined in five traditional onion cultivars (Allium cepa L.) from Tenerife (Guayonje, San Juan de la Rambla, Carrizal Alto, Carrizal Bajo and Masca) and a commercial cultivar (Texas Early Grano 502) grown under the same agronomic, soil and climatic conditions in order to find out differences between these cultivars. RESULTS: Carrizal Alto presented the highest K content and lowest P, Na, Fe, Zn, Mn and Se. Texas cultivar had the highest P, Mg and Se contents, and the lowest contents of Ca, Cu and Mn. There were clear differences in the mineral and trace elements contents between the two seed origins of San Juan de la Rambla cultivar. Many correlations were found between the parameters analyzed, emphasizing the Fe? Zn and Ca? Mn correlations. CONCLUSION: There were differences in the mineral and trace element composition between the onion cultivars. The environment and agronomic practices could affect the genetic information of the seeds, determining changes in the mineral and trace element composition. Linear discriminant analysis is a useful tool for differentiating onion samples according to cultivar and seed origin. Copyright © 2008 Society of Chemical Industry 相似文献
994.
Barros-Velázquez J Carreira L Franco C Vázquez BI Fente C Cepeda A 《Journal of food protection》2003,66(11):2085-2092
The effect of an advanced vacuum skin packaging system on the microbiological and physicochemical properties of fresh retail cuts of beef (including meat portions from six different anatomical regions) stored at 4 degrees C was compared with the effect of traditional vacuum packaging. The vacuum skin packaging system whose effect on meat quality was evaluated in this work displayed two remarkable features: (i) the instantaneous heating of the lower surface of the upper film of the package before the film descended over the meat surface and (ii) the tight disposition of the plastic film on the meat surface, which avoided wrinkles and purges. Throughout storage at 4 degrees C, rates of bacterial growth were statistically significantly slower in beef portions processed with the vacuum skin packaging system than in those processed with traditional vacuum packaging, with average differences of 2.07, 1.60, and 1.25 log CFU/g in counts of aerobic mesophiles, anaerobes, and lactic acid bacteria, respectively. pH values were statistically significantly lower for beef portions packaged with the vacuum skin system than for those that were vacuum packaged in the traditional manner, probably because of the relative predominance of lactic acid bacteria observed in such samples, which coincided with both higher meat firmness values and a slower meat tenderization process. The vacuum skin system prevented the appearance of undesirable coloration on the meat surface and also significantly improved the commercial color of the meat as determined on the basis of luminosity (L*) and the redness (a*). Overall, the quality (as determined by microbiological and physicochemical analyses and by visual examination) of fresh retail cuts of beef packaged with the vacuum skin system and stored at 4 degrees C was higher than that of meat samples processed with the traditional vacuum-packaging system. 相似文献
995.
Food authentication by PCR-based methods 总被引:1,自引:1,他引:1
Isabel Mafra Isabel M. P. L. V. O. Ferreira M. Beatriz P. P. Oliveira 《European Food Research and Technology》2008,227(3):649-665
Food authenticity is presently a subject of great concern to food authorities, as the incorrect labelling of foodstuffs can
represent a commercial fraud. The implication of misleading labelling can be much more important concerning the presence of
potentially allergenic foods. The need to support food labelling has provided the development of analytical techniques for
the analysis of food ingredients. In the last years, several methods based on polymerase chain reaction (PCR) have been proposed
as useful means for identifying species of origin in foods, as well as food allergens and genetically modified organisms (GMO),
due to their high specificity and sensitivity, as well as rapid processing time and low cost. This work intends to provide
an updated and extensive overview on the PCR-based methods for food authentication, including also methods for allergens and
GMO the detection in foods. 相似文献
996.
Beatriz Miralles Ingolf Krause Mercedes Ramos Lourdes Amigo 《International Dairy Journal》2006,16(12):1448-1453
Capillary electrophoresis (CE) and immobilized pH gradient isoelectric focusing were applied for the determination of the addition of isoelectric casein, rennet casein and sodium caseinate to processed cheeses of known composition containing different dairy products. Both methods allowed the determination of these protein ingredients by analysing the intact κ-CN. The comparison of the quantitative determination by both techniques demonstrated that they presented similar recoveries for isoelectric casein, but for sodium caseinate, a considerably better recovery was obtained by using the isoelectric focusing method (85.6% versus 47.2%). However, CE showed higher precision. CE was applied for the determination of the addition of rennet casein by the use of a calibration curve calculated by plotting the peak area ratio ∑β-CN A/para-κ-CN in the electropherograms versus the content of rennet casein of known composition cheeses from the same manufacture batch. This approach gave recoveries of added rennet casein between 94% and 102%. 相似文献
997.
Meat texture and some biochemical characteristics that could influence meat tenderness were studied in rabbit loins. Rabbits from three synthetic lines were compared, lines V and A selected for litter size at weaning and line R selected for growth rate between weaning and slaughter time. The activities of cathepsins, collagen content and textural properties measured by Warner-Bratzler (WB) shear device and by the texture profile analyses (TPA) test were measured. Line R was more tender than line V and line A had an intermediate tenderness, Rabbit meat from line R had higher activity of cathepsins B and B + L, lower total collagen content and lower cohesiveness, springiness and chewiness, shear force and total work (area under the curve obtained with WB device) than line V. Line A had an intermediate texture between lines R and V. Our results show evidence of genetic variation between lines in rabbit meat tenderness. 相似文献
998.
The levels of free and total tryptophan and of 5-hydroxytryptophan (5-HTP) were investigated in green and roasted grains and beverages of Coffea arabica L. (Arabica) and Coffea canephora Pierre var. robusta (Robusta). Grains were light, medium and dark roasted. Free and protein tryptophan were extracted before and after hydrolysis. The levels of tryptophan and 5-HTP were quantified simultaneously by ion-pair HPLC and fluorimetric detection after derivatisation with o-phthalaldehyde. Robusta green coffee had higher total and protein tryptophan, whereas Arabica had higher free tryptophan levels. 5-HTP was not detected in the samples before and after roasting. Free tryptophan was completely degraded during roasting. Roasting significantly affected protein tryptophan. The rate of loss was smaller in Arabica compared to Robusta at every roasting degree. A beverage prepared the Brazilian way with a medium-roasted coffee provided 1.4–2.5 mg tryptophan/50 ml cup. 相似文献
999.
Eva Pose-Juan Beatriz Cancho-Grande Raquel Rial-Otero Jesús Simal-Gndara 《Food Control》2006,17(12):1012-1017
The disappearance of the fungicides cyprodinil, fludioxonil, procymidone and vinclozoline, which are widely used to control grey mold in vineyards, from commercially sterilized white grape juice was studied. Fungicide losses from white grape juice stored at 40 °C were monitored for about 2 months in order to simulate in a fast way the shelf-life of the product at room temperature (about 1 year). The fungicides were determined by using a simple method based on a liquid–liquid extraction (LLE) and gas chromatographic separation, followed by mass spectrometric detection (GC–MSD). Fortified white grape juice subsamples were taken three times a week from the oven and the degradation of the fungicides monitored for 56 days. The half-lives at 40 °C for vinclozoline and procymidone were found to be 11 and 20 days, respectively. Those for the more recently introduced fungicides fludioxonil and cyprodinil were somewhat longer (33 and 44 days, respectively). Based on the first-order rate constants obtained, the fungicides dissipated in the following sequence: vinclozoline (0.062 d−1) > procymidone (0.035 d−1) > fludioxonil (0.021 d−1) > cyprodinil (0.016 d−1). 相似文献
1000.
Francisco José García Paramio Isabel de la Torre Díez Beatriz Sainz de Abajo Miguel López-Coronado Sánchez-Fortún Joel J. P. C. Rodrigues 《Telecommunication Systems》2017,64(2):391-415
This article has the objective of obtaining detailed knowledge on the regulation of access to next generation networks (NGNs) and its effects on a specific country, specifically Spain, given that it can be used as a reference to gain a better perspective and draw several conclusions on what has been a global pursuit during a key period of time, 2007–2015, for the electronic communications market in the European Union, where the current and historical role and position of incumbent operators is critical. Focused on NGNs based on fibre to the home solutions and the collateral aspects that support their deployment (coexistence with older access networks based on copper pairs and maintained regulation regarding wholesale broadband transmission services), this paper takes up new issues: the opening of transmission infrastructure and installation and the regulation of new network infrastructures in buildings. In doing so, we obtain a model of infrastructure and service competition that is also regulated by price, which promotes the deployment of new networks. We have generically evaluated the effect of this model on the deployment of NGNs in Spain and its effects on coverage, access to broadband service and the market shares of the different operators. The conclusions describe a successful model to a large degree because except when addressing the strictly economic aspect of return on investment, the objectives proposed by the regulatory agency have been achieved to date (2015) and within a long-term horizon (2008–2023). Given that this phenomenon is not an exact science, the conclusions regarding the goodness of the model will always be subjective and nuanced; however, we indicate that it will be necessary to strengthen the path followed by the regulatory agency through the monitoring of resolutions that maintain a strong framework and sufficient security for operators and users. Certain issues that were not addressed should be studied, given that they have proven to be critical: geographical discrimination, fibre loop disaggregation, new prices for wholesale services that adapt reference offers and greater control of the replicability of retail services. We are facing an open model with a future, as the new measures (2015) of the Spanish regulatory agency show in terms of the near future. 相似文献