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41.
Daniele da Silva Bastos Maria do Pilar Gonçalves Cristina Tristão de Andrade Kátia Gomes de Lima Araújo Maria Helena Miguez da Rocha Leão 《Food and Bioproducts Processing》2012,90(4):683-692
The aim of this work was to obtain a new stable food product from cashew apple juice encapsulated by spray-drying technique using chitosan–whey protein isolate systems. The materials were evaluated according to their physicochemical stability during storage at different conditions and characterized with respect to their particle size distribution and structure. Encapsulated commercial and natural juices showed homogenous and unimodal particle size distribution with diameters ranging from 0.2 to 5.0 μm and from 0.2 to 40.0 μm, respectively. Both juices demonstrated higher physicochemical stability for vitamin C and color measurements than their respective non-encapsulated juices. X-ray diffractograms evidenced that the powder juices after the 140th day of storage were still in amorphous state. These results indicate that the new product was effective in protecting sensitive compounds present in the food matrix and it was also able to remain stable throughout the study period. 相似文献
42.
The ability to discriminate nestmates from non-nestmates in insect societies is essential to protect colonies from conspecific invaders. The acceptance threshold hypothesis predicts that organisms whose recognition systems classify recipients without errors should optimize the balance between acceptance and rejection. In this process, cuticular hydrocarbons play an important role as cues of recognition in social insects. The aims of this study were to determine whether guards exhibit a restrictive level of rejection towards chemically distinct individuals, becoming more permissive during the encounters with either nestmate or non-nestmate individuals bearing chemically similar profiles. The study demonstrates that Melipona asilvai (Hymenoptera: Apidae: Meliponini) guards exhibit a flexible system of nestmate recognition according to the degree of chemical similarity between the incoming forager and its own cuticular hydrocarbons profile. Guards became less restrictive in their acceptance rates when they encounter non-nestmates with highly similar chemical profiles, which they probably mistake for nestmates, hence broadening their acceptance level. 相似文献
43.
Ben‐Hur Ramos Ferreira Gonçalves Grazielly de Jesus Silva Silvania Farias Oliveira Pontes Rafael da Costa Ilhéu Fontan Antonio Silvio do Egito Sibelli Passini Barbosa Ferrão 《International Journal of Food Science & Technology》2016,51(7):1586-1593
Electrophoretic and chromatographic techniques were used to determine water‐soluble peptide profiles aiming to identify the adulteration of buffalo milk mozzarella cheese by the addition of cow's milk. Thus, cheeses were produced with contents of cow's milk varying from 0% to 100%, and the peptides extracted after production and after 20 days of refrigeration. Polyacrylamide gel electrophoresis under denaturing conditions in the presence of sodium dodecyl sulphate (SDS‐PAGE) identified a potential peptide marker of exclusively bovine origin with a size of about 21 kDa for the addition of cow's milk above 30%. Reverse‐phase high‐performance liquid chromatography (RP‐HPLC) indicated the existence of two potential peptides present in higher concentrations in buffalo milk and one exclusive for cow's milk, the latter making it possible to estimate the addition of cow's milk to buffalo milk. Six commercial brands of buffalo mozzarella cheese were evaluated, and indications of adulteration found in four of them. 相似文献
44.
The preparation of the 11.7Li2O–39.7WO3–10.9CaO–37.7P2O5 glass (pgLWCP) was based on a one-step heat treatment of the 6Li2O–18WO3–43CaO–33P2O5 (gLWCP) glass followed by leaching of the β-Ca2P2O7 phase formed during the crystallization process. The porous structure was formed in the region formerly occupied by the β-Ca2P2O7 phase. The gLWCP undergoes devitrification through surface crystallization. This process occurs after a thermal treatment in lower temperature and in a shorter period of time than that required for the complete crystallization. After acid leaching treatment, we obtained a core-/shell-like structure with a very well-defined dense glass (gLWCP)/porous glass (pgLWCP) interface. The pgLWCP exhibits reversible coloration–decoloration reactions. 相似文献
45.
Oxidative Stability and Changes in Chemical Composition of Extra Virgin Olive Oils After Short‐Term Deep‐Frying of French Fries 下载免费PDF全文
Emília Akil Vanessa Naciuk Castelo‐Branco André Mesquita Magalhães Costa Ana Lúcia do Amaral Vendramini Verônica Calado Alexandre Guedes Torres 《Journal of the American Oil Chemists' Society》2015,92(3):409-421
We aimed at investigating oxidative stability and changes in fatty acid and tocopherol composition of extra virgin olive oil (EVOO) in comparison with refined seed oils during short‐term deep‐frying of French fries, and changes in the composition of the French fries deep‐fried in EVOO. EVOO samples from Spain, Brazil, and Portugal, and refined seed oils of soybean and sunflower were studied. Oil samples were used for deep‐frying of French fries at 180 °C, for up to 75 min of successive frying. Tocopherol and fatty acid composition were determined in fresh and spent vegetable oils. Tocopherol, fatty acid, and volatile composition (by SPME–GC–MS) were also determined in French fries deep‐fried in EVOO. Oil oxidation was monitored by peroxide, acid, and p‐anisidine values, and by Rancimat after deep‐frying. Differential scanning calorimetry (DSC) analysis was used as a proxy of the quality of the spent oils. EVOOs presented the lowest degree of oleic and linoleic acids losses, low formation of free fatty acids and carbonyl compounds, and were highly stable after deep‐frying. In addition, oleic acid, tocopherols, and flavor compounds were transferred from EVOO into the French fries. In conclusion, EVOOs were more stable than refined seed oils during short‐term deep‐frying of French fries and also contributed to enhance the nutritional value, and possibly improve the flavor, of the fries prepared in EVOO. 相似文献
46.
Maternal Flaxseed Oil During Lactation Enhances Bone Development in Male Rat Pups 总被引:1,自引:0,他引:1 下载免费PDF全文
Aline D’Avila Pereira Danielle Cavalcante Ribeiro Fernanda Carvalho de Santana Aline de Sousa dos Santos Jorge Mancini-Filho Celly Cristina Alves do Nascimento-Saba Luis Guillermo Coca Velarde Carlos Alberto Soares da Costa Gilson Teles Boaventura 《Lipids》2016,51(8):923-929
Flaxseed oil is an alpha linolenic acid source important in the growth and body development stage; furthermore, this acid acts on adipose tissue and bone health. The aim of this study was to evaluate body composition, fatty acid composition, hormone profile, retroperitoneal adipocyte area and femur structure of pups at weaning, whose mothers were fed a diet containing flaxseed oil during lactation. After birth, pups were randomly assigned: control (C, n = 12) and flaxseed oil (FO, n = 12), rats whose mothers were treated with diet containing soybean or flaxseed oil. At 21 days, the pups were weaned and body mass, length, body composition, biochemical parameter, leptin, osteoprotegerin, osteocalcin, fatty acids composition, intra‐abdominal fat mass and femur structure were analyzed. FO showed (p < 0.05): higher body mass (+12 %) and length (+9 %); body fat mass (g, +45 %); bone mineral density (+8 %), bone mineral content (+55 %) and bone area (+35 %), osteocalcin (+173 %) and osteoprotegerin (+183 %). Arachidonic acid was lower (p < 0.0001), alpha‐linolenic and eicosapentaenoic were higher (p < 0.0001). Intra‐abdominal fat mass was higher (+25 %), however, the retroperitoneal adipocytes area was lower (?44 %). Femur mass (+10 %), distance between epiphyses (+4 %) and bone mineral density (+13 %) were higher. The study demonstrates that adequate flaxseed oil content during a lactation diet plays an important role in the development of pups. 相似文献
47.
Roseli de Souza Santos da Costa Flavia da Silva Santos Daniela de Barros Mucci Tânia Vignuda de Souza Fátima Lucia de Carvalho Sardinha Célia Regina Moutinho de Miranda Chaves Maria das Graças Tavares do Carmo 《Lipids》2016,51(12):1363-1373
The purpose of this study was to investigate the trans fatty acids (TFA) content and distribution in colostrum, mature milk, and diet of adolescent mothers, after TFA declaration in food labels became mandatory in Brazil. Participants were healthy adolescents (n 54, 15–19 years, 1–90 days postpartum) practicing exclusive breastfeeding. Milk samples were collected 3 days after delivery (colostrum) and in the third month postpartum (mature milk) by hand expression. The fatty acid composition of the milk samples was determined by gas chromatography. TFA intake corresponded to 1.23 % of total energy value. Total 18:2 TFA accounted for less than 0.5 % of the energy intake. The amount of total 18:1 TFA (mean ± SEM) was 1.9 % ± 0.14 in colostrum and 1.5 % ± 0.2 in mature milk. The total content of n‐3 PUFA was inversely correlated with the total content of 18:1 TFA in colostrum. Both in colostrum and in mature milk, vaccenic acid (11t‐18:1) was found to be the most abundant 18:1 trans isomer, followed by elaidic acid (9t‐18:1), whereas rumenic acid (9c,11t‐18:2 CLA) was the predominant 18:2 trans isomer. In conclusion, the levels of TFA of industrial sources found in the mother's diet and breast milk (colostrum and mature milk) showed a decrease in relation to those observed in studies conducted prior to the TFA labeling resolution in Brazil. However, the current low intake levels of n‐3 LCPUFA and DHA content in the milk of lactating adolescents may be insufficient for supporting adequate neurological development of the infants. 相似文献
48.
Ultrastructure of the digestive tract in neotropical carnivorous catfish Hemisorubim platyrhynchos (Valenciennes, 1840) (Siluriformes,Pimelodidae) 下载免费PDF全文
49.
Gleber Tacio Teixeira Rosana Ftima Teixeira Lomba Agatha Densy dos Santos Francisco Joo Francisco Cajaíba da Silva Regina Sandra Veiga Nascimento 《应用聚合物科学杂志》2014,131(12)
To prevent the degradation of the borehole and also the disintegration and dispersion of drilled cuttings, different shale stabilizing additives are used in water‐based drilling fluids (WBFs). Glycols, poly(ethylene glycol), glycerols, and polyglycerol derivatives, also called polyols, have been used to inhibit shales containing reactive clays in WBF. These additives are normally used in conjunction with KCl to reduce clay swelling and dispersion of drilled cuttings. Highly branched polymers have become an important field in current polymer science. Such materials typically exhibit compact, globular structures in combination with an exceptionally high number of sites with functional groups. They have unique properties that differ significantly from their linear counterparts, and the hyperbranched polyglycerol (hPG) is an important hyperbranched polymer that can be produced from an environmentally benign monomer, the glycerol carbonate. In this article, the clay inhibitive properties of hPG were evaluated by different test methods including bentonite inhibition test, cuttings recovery, and X‐ray diffraction measurements. The results show that the hPG has a great potential to be used as an environmental friendly inhibitor additive in WBFs. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40384. 相似文献
50.
Chayene G. Anchieta Daniela Sallet Edson L. Foletto Syllos S. da Silva Osvaldo Chiavone-Filho Claudio A.O. do Nascimento 《Ceramics International》2014
Ternary zinc spinel oxides such as Zn2SnO4, ZnAl2O4 and ZnFe2O4 were synthesized and characterized, and their activities in the photodegradation of phenol molecules were investigated. Zn2SnO4, ZnAl2O4 and ZnFe2O4 powders were synthesized by hydrothermal, metal–chitosan complexation and solvothermal routes, respectively. The face-centered cubic spinel structure of each material was confirmed by powder X-ray diffractometry (XRD) and its porous structure by N2 adsorption–desorption isotherms. The characterization of spinels was complemented with Fourier transform infrared spectroscopy (FTIR) and X-rays fluorescence (XRF), revealing the formation of spinel structures with high purity. The photocatalytic activity in the degradation of phenol was observed only with Zn2SnO4 oxide. Mineralization degree of phenol molecules by Zn2SnO4 photocatalyst determined by total organic carbon analysis (TOC) reached 80% at 360 min under sunlight. 相似文献