The jellies constitute an important alternative for the processing of fruits, adding greater economic and nutritional value. The objective of this study was to evaluate the effects of different concentrations of pulp, sugar and maltodextrin on the physical-chemical and textural characteristics of kiwifruit jelly with lemon grass tea. Factorial design 23 was used with 3 replicates at the central point, resulting in 11 experiments with variation of sugar percentages (30, 40 and 50%), pulp (50, 60 and 70%) and maltodextrin (5, 10 and 15%). Water content, moisture content, total soluble solids (TSS), total titratable acidity (TTA), ashes, pH, reducing sugars, non-sugars were evaluated for the following physico-chemical parameters: reducers, total sugars, lipids and vitamin C. Regarding the texture profile, the following parameters were evaluated: hardness, cohesiveness, chewing, gummy and adhesiveness. It was found that among the analyzed variables, the ones that were considered as significant and/or predictive according to ANOVA and the F test were: (moisture, total solids, carbohydrates and vitamin C), through the graphs of the surfaces of responses observed that the percentage of pulp and maltodextrin used was proportional to the increase in moisture content, vitamin C, total solids and carbohydrates. The G2 experiment presented the lowest values of moisture and water activity, and higher carbohydrate contents, total solids and cohesiveness, in which it was formulated with the sugar concentration (-1) and pulp and maltodextrin (+1). The development of kiwi jelly with lemon grass tea is an excellent alternative for the use of the raw material, since it is a product with high nutritional value, stability during storage and potential for consumer acceptance.

Citron watermelon is an agricultural product of excellent economic potential. Its seeds are widely used for oil extraction, serving as an energy source, showing nutritional characteristics that make them a suitable product to be studied. Thus, the objective was to characterize citron watermelon seeds regarding their physicochemical composition, in addition to determining drying kinetics, fitting mathematical models to the data, and determining the effective diffusivity coefficients and thermodynamic properties. The seeds were dried in a convective dryer, varying the drying temperature, with air velocity of 1.0 m s-1. With the increase in drying temperature, there were reductions in moisture content, water activity (aw), ash concentration, total titratable acidity, lipids and reducing sugar. Citron watermelon seeds are rich in lipids and ash, have low sugar concentration and low acidity; their drying kinetics was very well described by the Two Terms and Approximation of Diffusion models, followed by the models of Midilli and Page, which resulted in acceptable fits. Effective diffusivity accompanied the increase in drying temperature, and this behavior was well fitted by an Arrhenius-type equation. Enthalpy and entropy variations were reduced with drying temperature, with increments in Gibbs free energy.

The objective of this study was to perform the kinetics of peach drying and to adjust the experimental data obtained to empirical and diffusive mathematical models to evaluate the effect of temperature on the physical-chemical quality of the final product. The drying experiments were performed in an air circulation dryer with a velocity of 1.5 m s-1, the drying kinetics were performed at temperatures of 60, 70 and 80 °C. Among the mathematical models applied, the Page model was the one that best fit the experimental data, because it presents greater efficiency in the description of the drying process. The decrease in the drying rate from the initial time to the end of the process was observed, increasing the temperature of the air caused a reduction in the drying time. It was verified through the analytical solution of the diffusion equation with infinite wall geometry that the increase of the drying temperature caused the increase of the diffusivity and convective coefficient of heat transfer. Through the Biot number, it can be stated that the first-type boundary condition would also describe the process satisfactorily. The fresh peach slices present high water content and water activity and the drying effect caused significant differences in all physical-chemical parameters analyzed.

Pitaya and acerola are fruits rich in nutrients and can be used in blends formulation in order to improve the sensory characteristics of both pulps in isolation and complement each other in terms of nutritional aspects. Thus, the aim of this research was to develop different blends of pitaya pulp with acerola and choose the best formulation based on physical-chemical and colorimetric characteristics. Three blends formulations were prepared: F1-90% pitaya and 10% acerola; F2-70% pitaya and 30% acerola; and F3-50% pitaya and 50% acerola. The formulations were evaluated for physical-chemical parameters of water activity, water content, ash, total soluble solids (SST), pH, total titratable acidity (ATT), SST/ATT ratio, ascorbic acid, proteins, lipids, sugars totals, reducers and non-reducers and colorimetric analysis. The obtained data were subjected to variance analysis (ANOVA) and to comparison between means by the Tukey test at 5% probability. The formulation F1 stood out when compared to the others. The parameters pH, soluble solids, ratio SS/ATT, ash, water content, water activity, proteins, sugars, luminosity and hue angle were the ones that gave the formulation F1 the best results. However, it is noteworthy that the formulation F3 presented a greater amount of ascorbic acid and higher values of a, b and chroma in the colorimetric analysis. The use of these fruits allows to obtain an innovative product with excellent nutritional and functional characteristics. The blend is a viable alternative for the use of perishable and seasonal fruits, adding greater economic value to the very promising product to the market.

The present work had as objective to determine the kinetics of drying of the chili pepper, to adjust different mathematical models to the experimental values as a function of the water content and to characterize the same in it’s in natura form and after the drying in the temperatures of 60, 70 and 80 °C. The samples were weighted periodically until reaching the equilibrium. The mathematical models of Wang and Singh, Henderson and Pabis, Newton, Page and Thompson were adjusted to the experimental data. The best adjustment was determined in relation to the highest values of the coefficient of determination (R2) and Mean Square Deviation (MSD). The obtained results showed that the drying of the pepper is influenced by the temperature of the drying air. It is concluded that the model of Henderson and Pabis was the one that best fit to the experimental data. The increase of the drying temperature promoted a reduction in the time required for the peppers to reach the moisture of the hygroscopic balance. The parameters of acidity, lipids and proteins remained close at the different drying temperatures used, however higher when compared to the samples in natura. It can be noticed that ashes and vitamin C have suffered considerable decrease as the temperature increased, as a result of the chemical transformations that occurred in the peppers due to heat exposure and loss of moisture.