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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.

The present article aims to apply two conservation techniques (convective drying and lyophilization) to the jabuticaba peels and to characterize the powders obtained regarding the physicochemical parameters and bioactive compounds, thus evaluating their effect on their composition. Convective drying of the shells was performed in an air circulation oven at 50 °C and 1.0 m.s-1 air velocity for 24h, and lyophilization was performed at -50 °C for 48 h. In natura peels and powders obtained were characterized by the following physicochemical parameters: moisture, ash, lipids, protein, crude fiber, carbohydrates, water activity, pH, acidity, reducing sugars, total soluble solids; and bioactive compounds: anthocyanins, flavonoids, total phenolic compounds and antioxidant activity by ABTS. The use of jabuticaba bark in natura and after drying in flour form are viable for the development of new products, as a way to minimize the disposal of residues produced by the agrifood industry. Through the results obtained the jabuticaba bark flour was considered to be a source of phenolic compounds with antioxidant activity and fiber and could be considered a functional food. Comparing the drying techniques used, the lyophilization stood out because it presented a better preservation of the physicochemical parameters and the bioactive compounds.

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.

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