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991.
Measurements and thermodynamic modeling of the solubility of squalene in supercritical carbon dioxide 总被引:1,自引:0,他引:1
Hugo Alexander Martinez-Correa Daniela Caio André Gomes Silvia Lury Kanehisa Fernando Antonio Cabral 《Journal of food engineering》2010
The solubility of squalene in supercritical carbon dioxide (SC-CO2) was measured and it was analyzed together with the values obtained by Catchpole and von Kamp (1997). The results showed that the experimental values obtained in this work agreed with the order of magnitude of those reported in the literature and correlated well with the Chrastil equation. The thermodynamic modeling using the Peng–Robinson equation of state only correlated well with the experimental values obtained when the critical properties and acentric factor reported by Ruivo et al. (2004) were used. The values predicted for the solubility of squalene in SC-CO2 using modeling employing the GC-EOS, were only of the same order of magnitude as the experimental values for pressures below 200 bar, and its performance was influenced by the value of the critical hard sphere diameter. 相似文献
992.
Andréa G. Antonio Renata S. Moraes Daniel Perrone Lucianne C. Maia Kátia Regina N. Santos Natália L.P. Iório Adriana Farah 《Food chemistry》2010
Coffee beverage has been associated with antibacterial activity against Streptococcus mutans, a cariogenic bacterium. This study aimed at identifying natural compounds in coffee that contribute to such activity and investigate the influence of species, roasting and decaffeination on it. Coffee chemical compounds and aqueous extracts of green and roasted regular and decaffeinated Coffea arabica and Coffea canephora beans were tested. MIC, biofilm inhibition and biofilm reduction results were correlated with the concentration of coffee compounds in the extracts. 5-Caffeoylquinic acid, trigonelline and caffeic acid solutions showed bacteriostatic activity (MIC = 0.8 mg/mL). Lighter and regular extracts showed higher inhibitory activity than darker and decaffeinated extracts, with an inverse correlation between bacterial colony-forming units and roasting degree. Only regular C. canephora extracts showed biofilm formation inhibition. The joint effect of chlorogenic acids, trigonelline and caffeine or other compounds removed by decaffeination seems to be one of the causes for coffee antibacterial activity against S. mutans. 相似文献
993.
Samir Ananou Margarita Garriga Anna Jofré Teresa Aymerich Antonio Gálvez Mercedes Maqueda Manuel Martínez-Bueno Eva Valdivia 《Meat science》2010
The single and combined effects of enterocin AS-48 and high hydrostatic pressure (HHP) on Listeria monocytogenes, Salmonellaenterica, and Staphylococcus aureus was investigated in fuet (a low acid fermented sausage) during ripening and storage at 7 °C or at room temperature. AS-48 (148 AU g−1) caused a drastic 5.5 log cfu g−1 decrease in L. monocytogenes (P < 0.001) and a significant (P < 0.01) inhibition (1.79 logs) for Salmonella at the end of ripening (10 d). After pressurization (400 MPa) and storage Listeria counts remained below 5 cfu g−1 in all fuets containing AS-48 (pressurized or not). HHP alone had no anti-Listeria effect. HHP treatment significantly reduced Salmonella counts, with lowest levels in pressurized fuets with AS-48. S. aureus showed similar growth for all treatments and storage conditions. These results indicate that AS-48 can be applied alone to control L. monocytogenes and combined with HHP treatment to control Salmonella in fuets. 相似文献
994.
Seventy-five yearling bulls of the “Asturiana de los Valles” northern-Spanish beef breed (double-muscled, mh/mh, n = 24; heterozygous, mh/+, n = 26; normal, +/+, n = 25) were produced under intensive conditions and the effects of double-muscling genotype on trans-18:1 and CLA isomer profiles were examined. Total trans-18:1 contents, measured as percentages of total fatty acid methyl esters, were 10.98–15.07% in backfat and 8.64–9.46% in muscle, and the major isomer was 10t-18:1 in all animals. In mh/+ animals, 11t-18:1 was the second most abundant trans isomer in muscle whereas in mh/mh and +/+ animals 11t-18:1 and 13t/14t-18:1 were relatively similar. Total CLA percentages were 0.71–0.85% in backfat and 0.32–0.40% in muscle. The highest total CLA percentage found was in mh/+, intermediate in +/+ and lowest in mh/mh animals (P < 0.05). Heterozygous animals had significantly higher percentages of 9c,11t- (P < 0.01), 11t,13c- (P < 0.01) and 9c,11c-18:2 (P < 0.05) and also significantly higher percentages of the sum of 9c,11t-/11t,13c-/11t,13t-18:2. Overall, mh/+ animals produced meat with a slightly better trans and CLA profile (i.e., less 10t-18:1 and more 11t-18:1 and 9c,11t-18:2) than other genotypes, however, further improvements would still be necessary to achieve a profile with a positive health image. 相似文献
995.
The purpose of this study was to evaluate the use of Lactobacillus plantarum, isolated from table olives "Bella di Cerignola," a traditional variety of Apulian region (Southern Italy), as a starter for this kind of food. We focused on the interaction of the starter with the natural occurring microflora, the quantitative/qualitative composition of yeast population, the decrease of pH, and the content of organic acids. After a preliminary characterization, 3 strains of Lb. plantarum, selected for their probiotic and technological performances, were used as a multiple-strain starter and inoculated (approximately 2%) in olives, processed according to Spanish style, brined at 8% and 10% of NaCl and added with 0.5% of glucose. The combination of the starter and glucose assured a correct fermentation course, decreasing the pH up to a safe value (4.3 to 4.5) and controlled the growth of yeasts. The concentrations of both L- and D-lactic acids increased throughout the fermentation, while citric and malic acids (both the isomers D and L) remained at low levels (0.2 to 0.4 g/L). Concerning yeast species, Candida guilliermondii was mainly isolated at the beginning (7 to 14 d), while C. famata prevailed at the end of fermentation. PRACTICAL APPLICATIONS: To the question "How to standardize and maintain quality of "Bella di Cerignola" olives (Southern Italy)" we can suggest the following answer: use Lb. plantarum and a low amount of glucose (0.5%). The result is a decrease of the pH below the safety break point. 相似文献
996.
Antonio Bevilacqua Marianna Cannarsi Mariangela Gallo Milena Sinigaglia Maria Rosaria Corbo 《Journal of food science》2010,75(1):M53-M60
ABSTRACT: Enterobacter cloacae can be recovered in the spontaneous fermentations of Italian table olives. In this study, the effects of salt (20 to 100 g/L), temperature (10 to 37 °C), pH (4 to 5 and 8 to 10), p -coumaric and vanillic acids (0.5 to 2 g/L), and the acidification of the medium through lactic, citric, and ascorbic acids were investigated on 15 strains of E. cloacae , isolated from Italian table olives "Bella di Cerignola." Finally, a confirmatory experiment in synthetic brine was run. The strains were inhibited only by an NaCl amount of 70 to 80 g/L and by p -coumaric acid; on the other hand, they showed the ability to grow also at low temperatures (10 to 15 °C). The confirmatory experiment highlighted their ability to survive both at 15 °C and at pH 5. Enterobacter cloacae could be a real problem for the fermentation of table olives in southern Italy; some hurdles could be used (salt or brine acidification), but some environmental conditions (for example, the temperature) should be controlled carefully to maintain olive safety at acceptable levels. 相似文献
997.
Nutrition facts and functional potential of quinoa (Chenopodium quinoa willd.), an ancient Andean grain: a review 总被引:3,自引:0,他引:3
Antonio Vega‐Gálvez Margarita Miranda Judith Vergara Elsa Uribe Luis Puente Enrique A Martínez 《Journal of the science of food and agriculture》2010,90(15):2541-2547
Quinoa, Chenopodium quinoa Willd., is an Amaranthacean, stress‐tolerant plant cultivated along the Andes for the last 7000 years, challenging highly different environmental conditions ranging from Bolivia, up to 4.500 m of altitude, to sea level, in Chile. Its grains have higher nutritive value than traditional cereals and it is a promising worldwide cultivar for human consumption and nutrition. The quinoa has been called a pseudo‐cereal for botanical reasons but also because of its unusual composition and exceptional balance between oil, protein and fat. The quinoa is an excellent example of ‘functional food’ that aims at lowering the risk of various diseases. Functional properties are given also by minerals, vitamins, fatty acids and antioxidants that can make a strong contribution to human nutrition, particularly to protect cell membranes, with proven good results in brain neuronal functions. Its minerals work as cofactors in antioxidant enzymes, adding higher value to its rich proteins. Quinoa also contains phytohormones, which offer an advantage over other plant foods for human nutrition. Copyright © 2010 Society of Chemical Industry 相似文献
998.
Grace F. Ghesti Julio L. de Macedo Valdeilson S. Braga Antonio T. C. P. de Souza Vicente C. I. Parente Esdras S. Figuerêdo Inês S. Resck José A. Dias Sílvia C. L. Dias 《Journal of the American Oil Chemists' Society》2006,83(7):597-601
Biodiesel (FA esters) has become very attractive as an alternative diesel fuel owing to its environmental benefits. Transesterification
is the most usual and important method to make biodiesel from vegetable oils. This article investigates the potential for
using Raman spectroscopy to monitor and quantify the transesterification of soybean oil to yield ethyl esters. The differences
observed in the Raman spectra of soybean oil after transesterification were a peak at 2932 cm−1 (
), the displacement of the v
C=O band from 1748 to 1739 cm−1, and the bands at 861 (v
R-C=O and v
C-C) and 372 cm−1 (δ
CO-O-C). Uni- and multivariate analysis methods were used to build several analytical curves and then applied in known samples,
treated as unknowns, to test their ability to predict concentrations. The best results were achieved by Raman/PLS calibration
models (where PLS=partial least squares regression) using an internal normalization standard (v
=C-H band). The correlation coefficient (R
2) values so obtained were 0.9985 for calibration and 0.9977 for validation. Univariate regression analysis between biodiesel
concentration and the increasing intensity of
band or v
C=O displacement showed R
2 values of 0.9983 and 0.9742, respectively. Although spectroscopic methods are less sensitive than chromatographic ones, the
data obtained by spectroscopy can be correlated with other techniques, allowing biodiesel yield and quality to be quickly
assessed. 相似文献
999.
Jos E. Bez ngel Marcos-Fernndez Rosa Lebrn-Aguilar Antonio Martínez-Richa 《Polymer》2006,47(26):8420-8429
A new convenient route for the synthesis of poly(-caprolactone) (PCL) with α,ω-telechelic diols' end-groups is presented. Synthesis of α,ω-telechelic PCL diols (HOPCLOH) was achieved by ring-opening polymerization (ROP) of -caprolactone (CL) catalyzed with ammonium decamolybdate (NH4)8[Mo10O34] and using diethylene glycol (DEG) as initiator. Obtained HOPCLOH was characterized by 1H and 13C NMR, FT-IR, GPC and MALDI-TOF. Comparative studies demonstrate that ammonium decamolybdate (NH4)8[Mo10O34] is better catalyst than Sn-octanoate (SnOct2) toward CL polymerization in presence of DEG, under the conditions tested. A biodegradable poly(ester-urethane-urea) derivative was efficiently prepared from synthesized HOPCLOH. Obtained polymer shows minor differences with respect to the properties recorded for a poly(ester-urethane-urea) obtained from commercial HOPCLOH. 相似文献
1000.
An evolutionary procedure based on cultural algorithms for the optimal design of adaptive wavelet filters based on lifting scheme is proposed. Numerical results of characterization, based on statistical experiment design, as well as validation, based on the comparison with a genetic optimization algorithm, are presented. Experimental results of the validation on two case studies for reducing uncertainty arising from noise in on-field corrosion rate measurements are highlighted. 相似文献