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The paper presents a new method for the reduction of waste production during juice processing through the reformulation of cloudy juices by ultrafiltration (UF), resulting in simultaneous production of a new type of cloudy juice of reduced sugar content. In contrast to the traditional juice production process, the final product was UF retentate. During UF, sugars were partially removed, while fibre and other macromolecular components present in a cloudy fraction, with health-promoting properties, were retained. Such treatment gives the possibility to reduce waste production during juice processing, because in the traditional approach, the cloudy fraction is usually treated as a waste after the clarification step. After UF in apple cloudy juice, the total content of soluble solids and sugars decreased from the initial values 11.0% and 10.4% to 9.2% and 8.8%, respectively; while in apple-beetroot cloudy juice, it reduced from 11.4% and 8.2% to 8.7% and 5.8%, respectively. At the same time, the cloudy fraction was retained and concentrated. The retention of soluble solids and sugars after the UF of apple juice was 66% and 67%, respectively, that is, 34% of soluble solids and 33% of the sugars were removed to the permeate. In apple-beetroot juice, 68% and 71% of soluble solids and sugars was retained, respectively.

The aim of this study was to investigate the possibility of honey spray drying with addition of maltodextrin and gum Arabic as drying agents. The influence of the concentration of the solution subjected to drying, the type and content of the drying agents upon the physical properties of obtained powders was examined. An attempt was undertaken to obtain powder with a honey content of more than 50% d.b. Spray drying of multifloral honey with the addition of maltodextrin and gum Arabic was carried out at inlet air temperature of 180°C, feed rate of 1 mL/s and rotational speed of a disc atomizer of 39,000 rpm. The properties of obtained powders were quantified in terms of moisture content, bulk density, Hausner ratio, apparent density, hygroscopicity and wettability. Using gum Arabic it was possible to obtain a product with a higher content of honey (67% solids) than in the case of maltodextrin (50% d.b.). However, the powders obtained with gum Arabic were characterised by worse physical properties: higher hygroscopicity and cohesion, and longer wetting time.

The application of low-temperature, dehumidified air-assisted spray drying was evaluated as a method to produce carrierfree powders of selected sugar-rich and acid-rich food materials: blackcurrant juice concentrate, mango puree, purple carrot juice concentrate, sauerkraut juice, kiwiberry pulp, and tomato pulp. As a consequence of decreased drying air humidity, inlet/outlet air temperature was lowered to 80/55°C. In order to validate this new approach, the conventional spray drying was conducted as well at 180/80°C inlet/outlet air temperature. The powder recovery, physical properties and color parameters of powders were determined. For blackcurrant juice concentrate, mango puree, purple carrot juice concentrate and sauerkraut juice it was possible to obtain carrier-free powders only by low-temperature drying, while for kiwiberry pulp and tomato pulp both variants of spray drying were effective. Decreased drying temperature positively influenced some properties of powders; i.e., median particle size diameter and hygroscopicity of the powders obtained by spray drying with dehumidified air were lower compared to those of the powders dried by conventional spray drying. Carrier-free powders of some raw materials (blackcurrant juice concentrate, mango puree, purple carrot juice concentrate, sauerkraut juice) were spray dried solely with dehumidified air, underlining its importance in the production of "clean label" products. [ABSTRACT FROM AUTHOR]

The paper aimed to compare the quality of rapeseed and honeydew honey powders, obtained by two methods of spray drying—traditional at a high temperature (inlet air 180 °C) and innovative low-temperature spray drying with the use of dehumidified air as a drying medium (inlet air 75 °C). Total polyphenol content, antioxidant activity, and the content and types of aromatic compounds were determined. In addition, Fourier-transform infrared spectroscopy (FTIR) coupled with chemometrics analyses was done. Powders obtained by the low-temperature spray drying method (with dehumidified air) were characterized by a higher content of polyphenols, antioxidant activity, and aromatic compounds, compared to powders obtained by the traditional method. Honeydew honey compared to rapeseed honey was characterized by a higher content of polyphenols, antioxidant activity, and composition of aromatic compounds. The results proved that the production method had a higher impact on the final properties of powders than the type of honey. [ABSTRACT FROM AUTHOR]

This study investigated the effects of osmotic dehydration and freezing on the kinetics and microstructure of vacuum-dried kiwiberry. Both fresh and previously frozen fruit were dehydrated in sucrose, maltitol and xylitol. Freezing and osmotic dehydration were selected as possible ways to improve the drying kinetics and positively influence the taste of the fruit. This experiment focused on the analysis of microstructural changes induced by applied processing methods using the X-ray microtomography technique. The results showed that the fruit pretreated in sucrose suffered the least structural damage as expressed by the largest condensation of small pores and thin cell walls. Freezing and xylitol resulted in the accumulation of larger pores and thicker walls. The most rapid drying time of 678-688 min was observed for unfrozen samples, dehydrated in sucrose and maltitol. Freezing slowed down the drying process, by 60-100 min, in comparison to the unfrozen samples. The applied mathematical models proved useful in predicting the kinetics of the drying process. The equation proposed by Midilli et al. provided the best fit for predicting the kinetics of the process. [ABSTRACT FROM AUTHOR]

The paper presents a new method for the reduction of waste production during juice processing through the reformulation of cloudy juices by ultrafiltration (UF), resulting in simultaneous production of a new type of cloudy juice of reduced sugar content. In contrast to the traditional juice production process, the final product was UF retentate. During UF, sugars were partially removed, while fibre and other macromolecular components present in a cloudy fraction, with health-promoting properties, were retained. Such treatment gives the possibility to reduce waste production during juice processing, because in the traditional approach, the cloudy fraction is usually treated as a waste after the clarification step. After UF in apple cloudy juice, the total content of soluble solids and sugars decreased from the initial values 11.0% and 10.4% to 9.2% and 8.8%, respectively; while in apple-beetroot cloudy juice, it reduced from 11.4% and 8.2% to 8.7% and 5.8%, respectively. At the same time, the cloudy fraction was retained and concentrated. The retention of soluble solids and sugars after the UF of apple juice was 66% and 67%, respectively, that is, 34% of soluble solids and 33% of the sugars were removed to the permeate. In apple-beetroot juice, 68% and 71% of soluble solids and sugars was retained, respectively. [ABSTRACT FROM AUTHOR]

The article describes an attempt to solve a real industrial problem, connected with the not very efficient enclosure of orange aroma during industrial microencapsulation, by the replacement of conventional mixing by single-stage homogenization during feed emulsion preparation. The powders obtained from solutions after 17 MPa homogenization were characterized by a lower water content and better flowability. The powders from solutions after 25 MPa homogenization showed better myrcene retention. An additional aim of this work was to investigate the physicochemical properties of powders obtained from the cyclone container and the drying chamber. This approach is connected with the fact that older generation spray dryers do not have systems protecting against local powder deposits in the chamber. In such situations, in order to reduce losses, the powder from the cyclone container and the one from chamber are mixed together, even if they have different properties. The results obtained show the significant differences between the powders collected from the cyclone container and the chamber of the spray dryer in terms of water content, bulk density, particle-size distribution and aroma retention. The powders obtained from the chamber were characterized by a lower water content, better flowability and a lower porosity value. Hierarchical cluster analysis confirmed the differences between the investigated microcapsule variants. [ABSTRACT FROM AUTHOR]

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