RESUMEN
Jambu, Acmella oleracea (L.), is a low-growing herb plant, with cylindrical, fleshy, decumbent and branched stem varying from 20 to 30 cm in height. It is an abundantly cultivated and consumed vegetable in the northern region of Brazil and usually consumed in preparations of typical foods of the Amazon region. So, this work aimed to compare the chemical composition and physical chemistry of powdered and jambu leaf mass. Acmella oleracea plants were selected, sanitized and their leaves were crushed (without adding water). The mass was dried in an oven with forced air circulation under different conditions of temperature (60, 70 and 80 °C) and relative humidity (13.09, 8.14 and 5.45%, respectively), in two layer thicknesses (0.5 and 1.0 cm). The physical, chemical, physicochemical parameters moisture content, water activity, ash, protein, lipids, pH, total titratable acidity and color were analyzed in powdered and fresh leaves. Contrast test was used to evaluate the interaction between the layer thicknesses at 5% level of significance. Considering the contrasts, the parameters total soluble solids, ash, protein and lipids do not differ from those in the fresh sample, demonstrating that these parameters are not modified or degraded with the drying conditions. The pH and color parameters differed from those of the fresh material, due to degradation, which can be linked to the rise in temperature sensitivity. The moisture content and water activity also differed and were reduced, contributing to conservation of the material. Contrast analysis made it possible to conclude that the physicochemical composition did not undergo modifications through the use of drying. In addition, a powdered material with reduced water activity was obtained.
RESUMEN
RESUMO O jenipapo (Genipa americana L.) é uma espécie nativa com importância medicinal, sendo amplamente utilizada no Brasil. Em função da necessidade de conhecimento à cerca do pré-processamento desta espécie, este trabalho foi desenvolvido com o objetivo de avaliar a cinética de secagem de folhas de jenipapo (G. americana L.), bem como determinar a difusividade efetiva da água durante o processo. As folhas foram coletadas com teor de água inicial de 2,30±0,05 (decimal b.s.), e submetidas à secagem em três condições de temperatura do ar (35,3; 46,0 e 65,0°C) até atingirem o teor de água de equilíbrio. Aos dados experimentais, ajustaram-se doze modelos matemáticos, recomendados para representar o processo de secagem de produtos agrícolas. As magnitudes do coeficiente de determinação (R2), do erro médio relativo (P), do erro médio estimado (SE) e do teste do qui-quadrado (χ2), foram utilizadas para verificar o grau de ajuste dos modelos. Os modelos de Henderson e Pabis modificado e Midilli apresentaram ajustes adequados aos dados experimentais, sendo o modelo de Midilli, em função de sua simplicidade, escolhido para representar a cinética de secagem das folhas de jenipapo. Aumentando a temperatura do ar de secagem de 35,3 para 46,0 e 65,0ºC houve redução no tempo de secagem das folhas de jenipapo de 91,1 para 62,5 e 24,2 horas, respectivamente. O coeficiente de difusão efetivo aumenta com a elevação da temperatura, e esta relação é descrita pela equação de Arrhenius, que apresenta energia de ativação para a difusão líquida de 33,9 kJ mol-1.
ABSTRACT The jenipapo (Genipa americana L.) is a native species with medicinal importance and is widely used in Brazil. Due to the need for knowledge about the preprocessing of this species, this work was developed to evaluate the drying kinetics of the jenipapo leaves (G. americana L.), and also to determine the effective diffusivity of water during the process. The leaves were collected with an initial moisture content of 2.30 ± 0.05 (decimal db), and dried in three conditions of air temperature (35.3, 46.0 and 65.0°C) until they reach the equilibrium moisture content. The experimental data set were twelve mathematical models, recommended to represent the drying process of agricultural products. The magnitudes of the coefficient of determination (R2), the mean relative error (P), the average estimated error (SE) and the chi-square (X2), were used in order to verify the adequacy level of the models. The Henderson, modified Pabis and Midilli models presented appropriate adjustments to the experimental data, with the model Midilli, due to its simplicity, chosen to represent the drying kinetics of the jenipapo leaves. By increasing the temperature of the drying air from 35.3 to 46.0 and 65.0ºC, there was a reduction in the drying time of the jenipapo leaves, from 91.1 to 62.5 and to 24.2 hours, respectively. The effective diffusion coefficient increases with the temperature’s raise, and this relationship is described by the Arrhenius equation, which shows activation energy for liquid diffusion of 33.9 kJ mol-1.
Asunto(s)
Plantas Medicinales/clasificación , Cinética , Hojas de la Planta/clasificación , Rubiaceae/clasificación , Conservación de AlimentosRESUMEN
This is the fifth case of the Bernard-Soulier syndrome to be described in the literature. The ante-natal period, the delivery and post-partum course without any complications. The platelet concentrations were used ante-natally and after delivery.
