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The effects of defatted hemp cake added to corn grits (at ratios of 0, 5, and 10% DM), the moisture content of the mixtures (15, 20, and 25%) and the temperature in the extruder ejection zone (150, 165, and 180°C) on the physical properties of extruded products have been investigated. Statistical optimization of investigated extrusion conditions using the response surface methodology was performed. The hemp cake was completely defatted by means of a supercritical CO2 extraction. The extrusion was performed on a laboratory single screw extruder and regulated by the following parameters: temperature in the dosing and compression zone (120 and 150°C), screw compression ratio (4 : 1), round die (4 mm). The change of extrusion process conditions significantly affected the physical properties of produced snacks. The expansion ratio ranged between 1.38 and 3.11, bulk density between 0.14 and 0.49 g/cm3, hardness between 18.15 and 70.62 N, fracturability from 3.65 to 10.38 mm, and the total colour change between 3.25 and 24.73.

The prospects of sparkling wine production by the 'Champenoise' method using alginate-immobilised yeast cells were examined. Grape varieties dominant in quantity were selected within the group of recommended and permitted varieties of Kutjevo vineyards, located in the eastern part of continental Croatia. Research revealed that there are no influential variations in the principal physicochemical and sensory characteristics between sparkling wines obtained through immobilised yeast and traditional sparkling method. The analysis of aroma compounds showed minor differences between samples. Observed oenological parameters assessed in the final products did not show any relevant oenological differences, with the exception of alcohol content, which was slightly higher in sparkling wines made with yeast cells immobilised with calcium alginate beads. According to this research, the sensory properties of the produced sparkling wines, compared to sparkling wine produced with free yeast, did not show any significant differences. On the full-scale obtained results indicate that some of the selected varieties can be sorted as suitable for the production of sparkling wine using immobilised yeast cells.

Durum semolina was replaced with 10, 15, and 20% of chestnut flour. Pasta was produced on a single screw extruder with the temperature profile of 80/90/90°C and on a laboratory minipress. Pasta samples were dried at room temperature and physical and sensory properties were determined. Generally, the chestnut flour addition to durum wheat pasta decreased optimum cooking time, hardness, cohesiveness, and chewiness, but increased cooking losses and pasta adhesiveness. Samples made on an extruder showed shorter optimum cooking times in relation to samples made on a minipress. Absorbed water was decreased with chestnut flour addition. Pasta made on an extruder showed a higher sensory score in comparison with pasta made on a minipress. The addition of chestnut flour influenced the colour of the samples. Samples made on an extruder showed darker colour in dried and cooked pasta samples in relation to minipress samples. In dried pasta samples, the extruder gave yellower samples in relation to the minipress, while in cooked pasta samples it was reversed. Overall, the extruder gave higher-quality pasta compared to the minipress.

Starches were isolated from three oat (Dzoker, Zvolen and Sampionka) and three barley (Barun, Zlatko and Vanessa) cultivars. The gelatinisation and retrogradation characteristics, pasting properties, swelling power, and solubility of the isolated starches were analysed. The gelatinisation onset temperatures varied from 59.4°C to 61.4°C for the oat starches (OS), and from 58.4°C to 62.2°C for the barley starches (BS). BS displayed a higher retrogradation enthalpy (ΔHr) than OS after 7 and 14 days storage at 4°C. OS-Sampionka had the lowest one while BS-Vanessa had the highest ΔHr after 7 and 14 days of storage. Significant differences in pasting properties were observed between the OS and BS. OS showed higher values of maximum viscosity than BS and followed the order: OS-Dzoker > OS-Sampionka > OS-Zvolen > BS-Vanessa > BS-Zlatko > BS-Barun. The breakdown viscosities of BS were considerably lower than those of OS. OS had higher swelling power and solubility values than BS. The higher swelling and solubility values of the oat starches in conjunction with lower retrogradation suggest different applications of these starches. The results showed that, while the barley starches are suitable for such applications where high stability is needed during heating and shearing (low breakdown values), the oat starches have a great potential for the applications where high stability during storage is needed (low ΔHr values). In addition, the barley starches are suitable for those applications where high water binding is undesirable, while the oat starches are applicable where low amounts of starch need to bind high proportions of water

Colour and texture are very important quality properties of all foods. In this work, the influence was investigated of different types of pectin on colour and textural properties in strawberry jams and low-calorie strawberry jams containing fructose and aspartame or fructose syrup and aspartame. The highest anthocyanin content and total phenol content were detected in strawberry jam samples prepared with low methoxy amidated pectin. During storage, after 4 and 6 weeks at both storage temperatures, room temperature and 4°C, anthocyanin content and total phenol content decreased. Also, free radical scavenging activity decreased during storage. As far as the texture parameters are concerned, namely firmness, consistency and cohesiveness, the highest values were found in strawberry jam samples prepared with high methoxyl pectin.

The effects of hydrocolloids pectin, carrageenan, as well as of pectin/carrageenan mixtures on gelatinisation, retrogradation, rheological characteristics, and swelling power of tapioca starch were studied with Brookfield rotational viscometer and differential scanning calorimeter (DSC). The results showed that hydrocolloids retarded the retrogradation of tapioca starch. Enthalpy and temperatures of gelatinisation, as well as solubility, did not vary significantly in starch-hydrocolloid systems. Viscosity of tapioca starch increased on the addition of hydrocolloids: the effect of carrageenan on viscosity was more remarkable than that of pectin.

The effects of trehalose, glucose, fructose, and sucrose on the gelatinisation and retrogradation properties of corn (CS) and tapioca (TS) starches were studied with differential scanning calorimetry (DSC). The results showed that the sugars affect gelatinisation and retrogradation of both starches, with the effect varying significantly between sugars. The addition of trehalose, glucose, fructose, and sucrose increased the gelatinisation temperatures and enthalpy of gelatinisation of corn and tapioca starches. The extent of increase followed the order: fructose < glucose < trehalose < sucrose with CS, and fructose < trehalose < sucrose < glucose with TS. The retrogradation studies showed that sugars of lower molecular weights (glucose and fructose) were less effective in the reduction of retrogradation than those of higher molecular weights (sucrose and trehalose). Trehalose retarded retrogradation of both corn and tapioca starches under all conditions investigated. Sucrose had the same effect on the corn starch retrogradation. The effects of other sugars depended on the type of starch, storage period, and storage temperature.