A D-optimal experimental design with three center points was used to evaluate the influence of spray-drying conditions on the physicochemical properties of a powdered product obtained by drying cactus pear juice. Drying was performed in a laboratory spray-dryer (Pulvis GB 22 model) at two inlet air temperatures (205 and 225°C), and two compressor air pressures (0.10 and 0.20 MPa). Commercial maltodextrins (10 and 20 DE) were used as carrier agents at two levels (18 and 23%). Moisture content and hygroscopicity were evaluated in the powder, and vitamin C retention and total color change were measured in the reconstituted product. Analysis of variance (ANOVA) was performed with a confidence level of 95% (p < 0.05). Moisture content of spray-dried powder and vitamin C retention of reconstituted product was mainly determined by the temperature-pressure, T*P, interaction. While for hygroscopicity, the pressure-concentration, P*C, interaction was the most important factor. The reconstituted product showed a slight change of total color (ΔE) with respect to natural juice and a significant effect of the maltodextrin concentration was found in this property.

The general aim of this study was to evaluate physicochemical properties, prebiotic activity and anticancer potential of jackfruit (Artocarpus heterophyllus) seed flour. The drying processes of jackfruit seeds were performed at 50, 60 and 70 °C in order to choose the optimal temperature for obtaining the flour based on drying time, polyphenol content and antioxidant capacity. The experimental values of the moisture ratio during jackfruit seed drying at different temperatures were obtained using Page’s equation to establish the drying time for the required moisture between 5 and 7% in the flour. The temperature of 60 °C was considered adequate for obtaining good flour and for performing its characterization. The chemical composition, total dietary fiber, functional properties and antioxidant capacity were then examined in the flour. The seed flour contains carbohydrates (73.87 g/100 g), dietary fiber (31 g/100 g), protein (14 g/100 g) and lipids (1 g/100 g). The lipid profile showed that the flour contained monounsaturated (4 g/100 g) and polyunsaturated (46 g/100 g) fatty acids. Sucrose, glucose, and fructose were found to be the predominant soluble sugars, and non-digestible oligosaccharides like 1-kestose were also found. The total polyphenol content was 2.42 mg of gallic acid/g of the sample; furthermore, the antioxidant capacity obtained by ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) was 901.45 µmol Trolox/100 g and 1607.87 µmol Trolox/100 g, respectively. The obtained flour exhibited good functional properties, such as water and oil absorption capacity, swelling power and emulsifier capacity. Additionally, this flour had a protective and preventive effect which is associated with the potential prebiotic activity in Lactobacillus casei and Bifidobacterium longum. These results demonstrate that jackfruit seed flour has good nutritional value and antioxidant and prebiotic activity, as well as potential protective effects and functional properties, making it an attractive food or ingredient in developing innovative functional products.

Measuring glass transition temperature is necessary for predicting the state and the behavior during the processing, distribution, and storage of many amorphous sugar-rich products. Therefore, the purpose of this study was to establish an improved calorimetric methodology to assess T _g in amorphous sugars. This method was created through melting crystal with differential scanning calorimetry (DSC) using the same principle proposed by Jiang, Liu, Bhandari, and Zhou ( 2008 Jiang, B. , Liu, Y. , Bhandari, B. and Zhou, W. 2008. Impact of caramelization on the glass transition temperature of several caramelized sugars. Part I: chemical analyses. Journal of Agricultural and Food Chemistry, 56: 5138–5147. [Crossref], [Web of Science ®] [Google Scholar] . Impact of caramelization on the glass transition temperature of several caramelized sugars. Part I: chemical analyses. Journal of Agricultural and Food Chemistry, 56, 5138–5147). Thermogravimetric analysis with simultaneous DSC was required to characterize the melting and thermal degradation temperatures of sugars. Thermograms showing the complete process of heating–cooling–reheating are proposed to determine the precise glass transition temperature during cooling (T _gC) or reheating (Tg _H), and to verify if the processed amorphous samples were created with or without thermal degradation. The melting temperature has little effect on the T _g value whereas the sugar was melted without thermal degradation. Thus, using this methodology the precise T _g value of amorphous sugars can be determined.

The objective of this study was to assess the effectiveness of the blends with different levels of lactose-maltodextrin (8:5, 10:5, and 12:5 % w/v) during the spray-drying of the passion fruit juice. The drying was carried out in a laboratory spray dryer (Pulvis GB 22 model) at two inlet air temperatures (180 and 190 ºC), and two air pressures (0.10 and 0.20 MPa). The moisture content, hygroscopicity and vitamin C retention were evaluated in the powder obtained. Response surface plots (p<0.05) showed that the lowest values of the moisture content and hygroscopicity were reached in the temperature range of 188-190 ºC and at 12:5 % (w/v) concentration of lactose-maltodextrin; the best vitamin C retention level occurred at 180 ºC and 0.2 MPa.