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The aim of the study was to investigate the effect of ultrasound treatment in osmotic solution, carried out at different time and solutions, on mechanical and thermal properties of cranberries. Ultrasound treatment was applied for 30 and 60 min in liquid mediums such as 61.5 % sucrose solution and 30 % sucrose solution with 0.1 % steviol glycosides addition. Before the ultrasound treatment samples were subjected to traditional operations (cutting, blanching). The traditional operations and ultrasonic treatment of whole fruits did not influence or slightly influenced dry matter content and mechanical properties. The cutting had impact on thermal properties to the highest extent due to the exposition of fruits’ flesh. The combination of cutting and sonication decreased thermal conductivity which suggests that mass transfer was more pronounced. The sonication had greater influence when compared to only ultrasonic treatment. Combined both cutting and blanching with ultrasonic treatment led to greater changes in cranberries properties.

The possibility of using the vacuum impregnation as a pretreatment before drying apple cubes was investigated. The impregnation was carried out for 4.5 min with the vacuum pressure of 0.01 MPa. The sucrose solution or a mixture of sucrose and the citric acid were used as infiltration liquids. Apple cubes were dried by convective drying (CD) (at temperature of 50 and 70 °C) or microwave-vacuum drying (MVD) (at power of microwaves 120 and 480 W). The drying kinetics was determined and quality factors (anti-oxidant activity, mechanical–rheological properties and colour changes) were analysed. Studies proved that the vacuum impregnation causes increasing of the drying dynamics (12.50–28.57 % during CD and 12.50–18.48 % during MVD). All impregnated apples were darker, yellower and susceptible for deformation or cutting than non-impregnated. The highest level of anti-oxidant activity was observed when two-component impregnant before MVD by power of 480 W was used.

The aim of the study was to determine the influence of four different growing locations of apples cv . ‘Jonagold’ in Europe on the drying kinetics and the physical properties of dried apple slices. The drying methods applied in the study (freeze-drying, convective drying, microwave-vacuum drying and combined drying) significantly affected the drying time, which was the shortest in the case of microwave vacuum drying. The geographical origin of the apples affected the chemical and physical properties of the raw material used for drying, and, consequently, the drying time. Water activity of dried samples was connected with the final dry matter, regardless of the geographical origin of the apples. Freeze-drying resulted in the lightest in colour products ( L* ), whereas microwave-vacuum dried products had the highest levels of yellow pigments ( b* ). The highest chroma and browning index values were noted for microwave-vacuum dried samples and were strongly influenced by the drying temperature. The mechanical properties of the apple slices were more dependent on the drying method and temperature of the process than on the geographical origin when the temperature exceeded 83 °C.

In Poland, Amelanchier berries are of considerable interest to both consumers and potential producers, which presents marketing challenges and opportunities. An attempt was made to preserve Amelanchier berries using a vacuum-microwave method of drying in order to determine its usefulness for producing microbiologically stable dried fruit with a high nutritional values. The berry variety “Prince William” ( Amelanchier canadensis ) was chosen as the experimental material. Vacuum-microwave drying was performed in two variants: (convective drying [CD] + vacuum microwave method [VMW]) after convective pre-drying of fruit and (VMW) without pre-drying. Unassisted CD was used as the reference method. Application of a vacuum-microwave drying method to Amelanchier berries makes it possible to obtain a stable preserved product of high-quality, yielding moderate shrinkage and good retention of bioactive compounds. An optimized method of vacuum-microwave drying, applied directly to frozen fruit, allows the retention of 70 % of cyanidin glycosides present in the raw material.

The study evaluated the functional properties of chokeberry and kale powders obtained by the fluidised-bed jet milling with drying (FJMD) method compared to the freeze-drying (FD) method. The powders obtained by the FJMD method were characterised by low water activity (<0.3), vitamins C content of 320.2 mg/100 g d.m. for kale powder, total content of polyphenols of 1864.2 mg/100 g d.m. for chokeberry powder, antioxidant activity of 37.0 and 27.6 mmol Trolox/g d.m for chokeberry and kale powders respectively and sensory quality similar to raw material. The high content of vitamin C in the kale powder indicates the desirability of its greater use as a natural source of this vitamin. The properties of FJMD powders were similar to the functional properties of the FD powders, which indicate that the FJMD method can be very competitive as compared to FD method.

The effect of heat treatment (75 °C) and spray drying with the addition of Arabic gum (inlet/outlet air temperature 180/75 °C), on the diastase activity of multifloral honey (MH) and rape honey (RH) was investigated. The physical properties of the powders (particle size and morphology, water content and activity, bulk loose and tapped density, angle of repose, hygroscopicity) directly after drying and after 12 weeks of storage were studied. During heat treatment, diastase activity decreased gradually, to decline below limit values after 180 min. Diastase activity in the powders was lower than in fresh honeys, but it was concluded that temperature was not the only factor affecting this decrease. Powders were characterized by low water content and medium flowability, which was improved after storage due to particle size increase. Diastase activity in powders was stable during storage.

The aim of the work was to investigate the effect of extrusion-cooking process conditions on the structure and pasting properties of starch extrudates. In addition, the extrudates structure was observed using scanning electron microscopy (SEM) and confocal laser microscopy (CSLM). Wheat, corn and potato starch were extrusion-cooked with different process parameters (moisture content, screw speed, process temperature) in a single screw extruder. Results showed influence of the process parameters on extruded starches pasting properties. Viscosity measurements indicated that water content during starch extrusion is more important than process temperature. The extrudates structure observed with scanning electron and confocal laser microscopes showed that the main effect of extrusion-cooking was loss of the crystalline structure of the starch and the formation of a cellular structure of the extrudates. In extrudates processed at higher starch moisture content reduced the quantity and diameters of created cells was observed.

The cylindrical whirlpool is used to separate hot trub from beer wort. When the tank is being filled and the contained mixture is swirled, a phenomenon takes place the main principle of which is formation of a cone of residue in the center of the tank. This paper is aimed at further development of the research on symmetrization of the cone-accumulating flow during tank filling. Herein are presented average values of particles’ velocity while in rotational motion in a whirlpool tank of modified structure. The modification is a vertically reduced baffle attached to the tank’s bottom. The experiments were conducted for two different filling rates and three different baffle positions. Measurements of particles’ velocity were performed with the PIV method. Results have been presented in the form of surface of average particles’ velocity distribution for given radius values throughout the entire process. The most advantageous baffle positions were determined.

The article aimed at the evaluation of possible use of nephelometers to monitor changes of turbidity in cleaning solution while cleaning in flow. The results demonstrate the ability to control the duration of cleaning programs. The tests were carried out in a laboratory Clean in Place station and aimed to clean a 10-section plate heat exchanger contaminated by milk. On the basis of the data, the turbidity curves were calculated. On their basis, the kinetic of the cleaning process was revealed. Following turbidity data collection, the heat exchanger plates were also checked for remaining milk contamination. The proposed cleaning steps allow for the possibility to manipulate the cleaning program’s time, and, correspondingly, enable higher energy efficiency in the program. In comparison with the conventional cleaning program currently used in processing plants, our findings demonstrate that the proposed method to monitor turbidity reduces energy consumption by 40 % without decreasing cleanliness.