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991.
Ana Paula Billar dos Santos Marta Mitsui KushidaElisabete Maria Macedo Viegas Judite Lapa-Guimarães 《LWT》2014
A Quality Index Method (QIM) scheme for gutted and iced Acoupa weakfish (Cynoscion acoupa) was developed and its efficiency for freshness evaluation was compared with instrumental colour analysis, microbial and chemical methods. The QIM scheme comprises sensory evaluation of 14 parameters, reaching a total sum of 23 demerit points. The evolution of Quality Index (QI) was identical in two independent storage experiments and could be represented by the equation QI = 1.3593 × days − 0.3822 (R2 = 0.9614, P < 0.0001). The QIM results indicated a shelf life of 8–9 days, when the sensory quality was considered unacceptable. The storage time affected a∗ and b∗ values for fish gill and caudal fin, respectively. Psychrotrophic bacteria counts (PBC) increased at different rates during the iced storage of fish in three independent storage experiments, reaching the maximum recommended limit for marginally acceptable quality products of 107 CFU/g between 6 and 14 days. The shelf life of Acoupa weakfish estimated by QIM was slightly longer than that evaluated by PBC. The rate and pattern of total volatile base nitrogen and trimethylamine production was different in fish from three independent storage experiments. The use of QIM scheme was a reliable way of assessing freshness of Acoupa weakfish. 相似文献
992.
993.
María José Antón Belén Suárez Valles Ana García Hevia Anna Picinelli Lobo 《Journal of food science》2014,79(1):S92-S99
Nine samples of Asturias cider have been analyzed for volatile, olfactometric, and sensorial profiles. The aromatic composition was mainly constituted by fusel alcohols and ethyl esters. Among the minor volatile compounds, fatty acids, volatile phenols, and alcohols were the main components. The olfactometric analysis revealed the existence of 55 aromatic areas, exhibiting a wide range of intensities. Components like amyl alcohols, 2‐phenylethanol, ethyl esters such as 2‐methylbutyrate, hexanoate and octanoate, hexanoic and octanoic acids 2‐phenylethyl acetate, 4‐ethyl guaiacol, and 4‐ethyl phenol could be considered as being part of the structure of cider aroma. The extract dilution analysis of one extract identified 2 volatile phenols (4‐ethyl guaiacol and 4‐ethyl phenol) among the most powerful odorants in cider. These components gave significant correlations with the sensory attributes sweet, spicy, and lees. 相似文献
994.
995.
Raquel?P.?F.?GuinéEmail author Inês?C.?Almeida Ana?C.?Correia Fernando?J.?Gon?alves 《Sensing and Instrumentation for Food Quality and Safety》2015,9(3):337-346
The main objective of the present work was to dry grapes of Crimson variety through different methodologies in order to find an alternative for the production of raisins. Different methodologies were used for drying: solar direct exposition in a greenhouse and in convective drying chambers with constant air flow at two temperatures: 50 and 60 °C. Some chemical analyses were made, namely for total sugars, acidity, total phenols, total anthocyanins and total tannins. Also some physical properties were evaluated, specifically color and texture. A sensorial analysis of the dried products was undertaken to evaluate the acceptability by consumers. The raisins produced by the different methodologies didn’t show significant differences at the chemical and physical levels. However, it was observed that the dried samples contained higher amounts of total phenolic compounds, anthocyanins and tannins in comparison to the fresh grapes. Sensory evaluation result showed that dried grapes produced using different methodologies was similar to commercial raisins. 相似文献
996.
Mongin D Juvé V Maioli P Crut A Del Fatti N Vallée F Sánchez-Iglesias A Pastoriza-Santos I Liz-Marzán LM 《Nano letters》2011,11(7):3016-3021
The acoustic vibrations of metal nanoparticles encapsulated in a dielectric shell (Ag@SiO(2)) were investigated using a time-resolved femtosecond technique. The measured vibration periods significantly differ from those predicted for the bare metal cores and, depending on the relative core and shell sizes, were found to be either larger or smaller than them. These results show that the vibration of the whole core-shell particle is excited and detected. Moreover, vibrational periods are in excellent agreement with the predictions of a model based on continuum thermoelasticity. However, such agreement is obtained only if a good mechanical contact of the metal and dielectric parts of the core-shell particle is assumed, providing a unique way to probe this contact in multimaterial or hybrid nano-objects. 相似文献
997.
Bashshur Michael R.; Hernández Ana; González-Romá Vicente 《Canadian Metallurgical Quarterly》2011,96(3):558
The authors argue that over time the difference between team members' perception of the organizational support received by the team (or team climate for organizational support) and their manager's perception of the organizational support received by the team has an effect on important outcomes and emergent states, such as team performance and team positive and negative affect above and beyond the main effects of climate perceptions themselves. With a longitudinal sample of 179 teams at Time 1 and 154 teams at Time 2, the authors tested their predictions using a combined polynomial regression and response surface analyses approach. The results supported the authors' predictions. When team managers and team members' perceptions of organizational support were high and in agreement, outcomes were maximized. When team managers and team members disagreed, team negative affect increased and team performance and team positive affect decreased. The negative effects of disagreement were most amplified when managers perceived that the team received higher levels of support than did the team itself. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
998.
In this paper, we consider a semiparametric partially linear regression model where missing data occur in the response. We
derive the asymptotic behavior of the robust estimators for the regression parameter and of the weighted simplified location
estimator introduced in Bianco et al. (Comput. Stat. Data Anal. 54:546–564, 2010a). For the latter, consistency results and the asymptotic distribution are derived when the missing probability is known and
also when it is estimated. 相似文献
999.
We report the first example of a Ni(II) complex that demonstrates sensitiser function in a Dye-Sensitised Solar Cell (DSSC). Complexes [Ni(dcbpy)(qdt)] (1), [Ni(decbpy)(qdt)] (2) and [Ni(decbpy)Cl2] (3) (where dcbpy = 4,4′-dicarboxy-2,2′-bipyridine; decbpy = 4,4′-di(CO2Et)-2,2′-bipyridine; and qdt = quinoxaline-2,3-dithiolate) have been prepared. Characterisation was carried out using electrochemical, spectroscopic and computational techniques. Intensive visible transitions of 1 and 2 have been assigned predominantly to Ligand-to-Ligand Charge Transfer (LLCT) from the qdt to the diimine ligand, suggesting appropriate charge separation for application in a photoelectrochemical device. TiO2 sensitised with 2, following charge injection, processes a recombination time significantly long for photovoltaic function. In a DSSC, using redox electrolyte, photocurrents and photovoltages of 0.293 mA and 521 mV were observed, with optimum values requiring TiCl4 post-treatment of TiO2 and co-adsorption of Chenodeoxycholic acid (Cheno). Although photovoltaic function was observed, the low photocurrent is attributed to a short-lived excited state lifetime resulting in poor charge injection from the Ni(II) sensitiser. 相似文献
1000.