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  • Author or Editor: E. Márki x
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This study was based on the production of an alcoholic beverage from apple using laboratory pervaporation equipment. Hungarian fruit brandy is called pálinka, which can be made by pot distiller or multistage distiller made of copper. In case of traditional pot still distillation the final product is gained from two separate distillations. Pervaporation is an energy efficient membrane process for separating liquid mixtures. Application of pervaporation to separate the product of the initial distillation leads to lower energy consumption than using double-distillation process. The aim of our work was to develop an alternative technology for the production of pálinka that integrates distillation and pervaporation.

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Consumer concern over artificial food additives has stimulated production of pigments from natural sources. The aim of this study was to examine the effects of process variables on the content of colour compounds (betaxanthin and betacyanin) in beetroot peel juice extracted by conventional method. In this research, the extraction processes were carried out according to the central composite design with different process variables. Quantitative measurements of the basic colour compounds in beetroot extract were performed using spectrophotometer. From our experiment, it was found that the most adequate extraction conditions, which gave the highest yield of colour compounds (952.5 mg l–1 of betaxanthin and 1361 mg l–1 of betacyanin), were extraction time 1 h, operating temperature 20 ºC, and solvent ratio 0.8 w/v. Being a conventional heating method, it is a simple and cost efficient process with relatively high yield.

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Our experiments were based on a model solution containing five of the main pineapple aroma components. Both sweeping-gas pervaporation and vacuum-pervaporation methods were carried out. Measurements were performed at different temperatures and feed flow rates. The purposes of this study were to examine applicability of the two pervaporation methods in reference to the pineapple aroma recovery, the effects of the operating parameters on the process, and modelling the pervaporation process by resistance-in-series model. Higher enrichment could be reached with vacuum-pervaporation than the sweeping-gas method. The separation process is determined by the diffusion of compounds in the membrane, thus the resistance in the boundary layer at liquid side is negligible. Based on performed experiments, the pervaporation process can be applied in beverage industry for aroma recovery.

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One of the most important enriching materials at the processing of alimentary pastes is the egg, which usage is limited because of its water content. Removing water from liquid whole egg with membrane processes, such as ultrafiltration (UF), nanofiltration (NF) and reverse osmosis (RO) was applied for raising the solid content at a temperature of 25 °C at constant flow rate. The separation procedures were carried out on laboratory scale equipments. The initial solid content of the liquid whole egg was 24 refractive (Ref%). The effects of different recirculation flow rates and transmembrane pressure differences were investigated on the permeate flux of the liquid egg. The product had up to 30, 35.5 and 36 Ref% solids in case of UF, NF and RO, respectively. From the resistance data it is obvious, that the polarization layer resistances (RP) determine the values of the permeate flux. The total solid content of permeate was 0.3 and 0.1 Ref% in case of nanofiltration and reverse osmosis, respectively. On the basis of experiments main data of a continuous pilot scale system were calculated and simplified cost estimation was performed using recent economic data of year 2011.

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