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Search Results: 1 - 10 of 542 matches for " yerba maté "
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Moisture migration during a tempering time after the heat treatment step in yerba maté processing
Schmalko,M.E.; Lovera,N.N.; Kolomiejec,G.C.;
Latin American applied research , 2011,
Abstract: the aim of this research was to study the effect of applying a tempering time to the branches of yerba maté after the heat treatment stage (or sapecado). assays were carried out in three industrial producers of misiones argentina. branches were obtained from the sapecador outlet and then, they were put in rest in order to form a bed. first, moisture content of leaves and twigs, separately, and then losses of mass of whole branches were measured. when the branches were put in rest in a bed during 30 min, 8.60 kg of water/100 kg of dry matter were transferred from the twigs to the leaves and 5.17 kg of water/ 100 kg of dry matter were lost by evaporation.
Extraction optimization of soluble compounds of yerba maté
Sambiassi, César;Escalada, Andrea M.;Schmalko, Miguel E.;
Brazilian Archives of Biology and Technology , 2002, DOI: 10.1590/S1516-89132002000200010
Abstract: the objective of this research was the extraction optimization of water soluble compounds of yerba maté. measures variables were extract concentration and weight of leaves and twigs. controlled variables were time and temperature of extraction and water/solid relation. a surface response method of three variables was used as experimental design, with 20 experiences in each case. the range of each variable, defined in the experimental design, was: extraction time, 13.2 to 46.8 minutes; temperature, 48.2 to 81.8°c and water solid relation, 4.64 to 11.36 g water/100 g of dry solid. extract weight varied from 13.14 to 29.56 g in leaves and 8.98 to 16.32 g in twigs (each one per 100 g of dry solid). extract concentration varied between 2.17 and 3.43 g/100 ml in leaves and between 1.32 and 2.31 g/100 ml in twigs. the results were fit to a linear equation in each case.
Moisture migration during a tempering time after the heat treatment step in yerba maté processing
M.E. Schmalko,N.N. Lovera,G.C. Kolomiejec
Latin American applied research , 2011,
Abstract: The aim of this research was to study the effect of applying a tempering time to the branches of yerba maté after the heat treatment stage (or sapecado). Assays were carried out in three industrial producers of Misiones Argentina. Branches were obtained from the sapecador outlet and then, they were put in rest in order to form a bed. First, moisture content of leaves and twigs, separately, and then losses of mass of whole branches were measured. When the branches were put in rest in a bed during 30 min, 8.60 kg of water/100 kg of dry matter were transferred from the twigs to the leaves and 5.17 kg of water/ 100 kg of dry matter were lost by evaporation.
Extraction optimization of soluble compounds of yerba maté
Sambiassi César,Escalada Andrea M.,Schmalko Miguel E.
Brazilian Archives of Biology and Technology , 2002,
Abstract: The objective of this research was the extraction optimization of water soluble compounds of yerba maté. Measures variables were extract concentration and weight of leaves and twigs. Controlled variables were time and temperature of extraction and water/solid relation. A surface response method of three variables was used as experimental design, with 20 experiences in each case. The range of each variable, defined in the experimental design, was: extraction time, 13.2 to 46.8 minutes; temperature, 48.2 to 81.8°C and water solid relation, 4.64 to 11.36 g water/100 g of dry solid. Extract weight varied from 13.14 to 29.56 g in leaves and 8.98 to 16.32 g in twigs (each one per 100 g of dry solid). Extract concentration varied between 2.17 and 3.43 g/100 ml in leaves and between 1.32 and 2.31 g/100 ml in twigs. The results were fit to a linear equation in each case.
Bioactive compounds content of chimarr?o infusions related to the moisture of yerba maté (Ilex Paraguariensis) leaves
Bastos, Deborah H. M.;Fornari, Ana Claudia;Queiroz, Yara S.;Torres, Elizabeth A. F. S.;
Brazilian Archives of Biology and Technology , 2006, DOI: 10.1590/S1516-89132006000400007
Abstract: the aim of this study was to evaluate the effects of the processing stages of yerba maté (ilex paraguariensis) on the moisture content of the leaves and the efficiency of the aqueous extraction of some bioactive substances. samples of yerba maté were analyzed for caffeine, phenolic acids (caffeic acid, 5-caffeoilquinic acid) and flavonoids (quercetin, kaempferol and myricetin) by hplc equipped with a diode array detector. processing widely influenced the caffeine and 5-caffeoilquinic acid content of the aqueous extract (p < 0.05), which was related to the moisture content of the leaves. caffeic acid was present in 45% of the in infusions from dried mate leaves. quercetin, myricetin and kaempferol were not detected.
Natural antioxidant from yerba maté (Ilex paraguariensis St. Hil.) prevents hamburger peroxidation
Ferreira, Erica Lemos;Sampaio, Geni Rodrigues;Torres, Elizabeth Aparecida Ferraz da Silva;Bastos, Deborah Helena Markowicz;
Brazilian Archives of Biology and Technology , 2011, DOI: 10.1590/S1516-89132011000400021
Abstract: the aim of this study was to evaluate whether yerba maté alcoholic extracts at very low concentrations (0.01 and 0.1%), prevent/retard lipid peroxidation in beef hamburgers without impairing sensory acceptability. for this tbars and hexanal levels, fatty acid profile and cholesterol oxides were evaluated as oxidation parameters in beef hamburgers during 90 days' storage. the addition of 0.01% yerba maté ethanolic extracts proved inefficient in restraining the lipid peroxidation while the addition of 0.1% resulted in efficient antioxidant activity. sensory evaluation of hamburger containing 0.1% yerba maté ethanolic extracts showed good acceptability. yerba maté ethanolic extracts could entirely or partially replace the phenolic synthetic antioxidants in beef hamburgers only when used at above legally allowed concentrations for antioxidant additives (0.01%).
The Effect of Mg2+, Cu2+ and Zn2+ pre-treatment on the color of yerba maté (Ilex paraguariensis) leaves
Scipioni, Griselda Patricia;Argüello, Beatriz del Valle;Schmalko, Miguel Eduardo;
Brazilian Archives of Biology and Technology , 2010, DOI: 10.1590/S1516-89132010000600027
Abstract: the aim of this work was to study the effect of alkaline blanching followed by an immersion in salt solutions of mg2+, cu2+ and zn2+ on color preservation of yerba maté leaves. the concentration of naoh in the alkaline solution influenced all of the color parameters. ion concentration and dipped time influenced only some color parameters. the color parameters of the product obtained with different treatments were different from the control sample (blanched with boiling water instead of alkaline blanching) and from the product obtained via industrial processing. the green color in the pre-treated and control samples was more intense (greater values of -a) and darker (low values of l and b). ionic and ash content in the leaves increased with the treatments.
Chlorophyll stability in yerba maté leaves in controlled atmospheres
Morawicki, Rubén O.;Schmalko, Miguel E.;K?nzig, Rodolfo G.;
Brazilian Archives of Biology and Technology , 1999, DOI: 10.1590/S1516-89131999000100012
Abstract: the objective of this research was to investigate the stability of chlorophyll in yerba maté leaves in controlled atmospheres of co2/air mixtures and different water activities at 25°c.two levels of water activity were selected corresponding to saturated salt solutions of licl (aw=0.113) and mgcl2(aw=0.330) and three levels of co2/air mixtures (0/100,20/80 and 40/60). the chlorophyll content was evaluated using a liquid chromatography hplc technique. experimental values varied between 2.16 and 0.61 mg/g of dry matter. for each sample, 5 determination were made during 58 days. experimental values were fitted to an equation describing a first order reaction. in all cases, the agreement was good with p<3 10-3. the initial concentration of chlorophyll dropped, in average, to 30.5% after 58 days. however, after comparing the velocity constants, no differences were found between them.
Physicochemical characterization of different trademarks of compound Yerba Maté and their herbs
Scipioni, Griselda Patricia;Ferreyra, Darío Jorge;Schmalko, Miguel Eduardo;
Brazilian Archives of Biology and Technology , 2007, DOI: 10.1590/S1516-89132007000400020
Abstract: the objectives of this study were to evaluate the physicochemical characteristics of the main herbs used in the mixture of yerba maté with other aromatic herbs and the characterization of the trademarks of compound yerba maté. moisture, water extract, total ash, acid-insoluble ash and caffeine concentration were determined. results showed higher values of moisture content, total and aci-insoluble ash and lower water extracts in the herbs. determinations were carried out in nine trademarks of compound yerba maté. in most cases they complied with the standards of the country with the exception of one trademark from argentina.
A novel procedure to measure the antioxidant capacity of Yerba maté extracts
Hartwig, Vanessa Graciela;Brumovsky, Luis Alberto;Fretes, Raquel María;Boado, Lucila Sánchez;
Ciência e Tecnologia de Alimentos , 2012, DOI: 10.1590/S0101-20612012005000022
Abstract: yerba maté extracts have in vitro antioxidant capacity attributed to the presence of polyphenolic compounds, mainly chlorogenic acids and dicaffeoylquinic acid derivatives. dpph is one of the most used assays to measure the antioxidant capacity of pure compounds and plant extracts. it is difficult to compare the results between studies because this assay is applied in too many different conditions by the different research groups. thus, in order to assess the antioxidant capacity of yerba maté extracts, the following procedure is proposed: 100 μl of an aqueous dilution of the extracts is mixed in duplicate with 3.0 ml of a dpph 'work solution in absolute methanol (100 μm.l-1), with an incubation time of 120 minutes in darkness at 37 ± 1 °c, and then absorbance is read at 517 nm against absolute methanol. the results should be expressed as ascorbic acid equivalents or trolox equivalents in mass percentage (g% dm, dry matter) in order to facilitate comparisons. the aoc of the ethanolic extracts ranged between 12.8 and 23.1 g te % dm and from 9.1 to 16.4 g aae % dm. the aoc determined by the dpph assay proposed in the present study can be related to the total polyphenolic content determined by the folin-ciocalteu assay.
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