Empirical models in the description of prickly pear shoot (Nopal) drying kinetics

Abstract

A B S T R A C TThe objective of this study was to describe the technological process involved in the drying kinetics of fresh-cut prickly pear shoots through numerical and analytical solutions. Shoots of two different prickly pear species were used, 'Gigante' and 'Miúda' . Drying was performed at different temperatures (50, 60, 70 and 80 °C) and weighing procedures were made continuously. The experimental data were expressed as moisture ratio. The Page model showed the best fit to the drying kinetics of minimally processed 'Gigante' and 'Miúda' prickly pear shoots, with the best coefficients of determination and Chi-square. Peleg and Wang & Singh models can not be used to simulate the drying of 'Gigante' and 'Miúda' prickly pear shoots within the evaluated range of temperatures, showing an incoherent graphic pattern.Modelos empíricos na descrição da cinética de secagem do broto da palma (Nopal) R E S U M OObjetivou-se neste trabalho descrever o processo tecnológico envolvido na cinética de secagem dos brotos da palma minimamente processados através de soluções numéricas e analíticas. Foram utilizados brotos provenientes de duas espécies de palma 'Gigante' e 'Miúda' . A secagem foi processada em diferentes temperaturas (50, 60, 70 e 80 °C). As pesagens foram efetuadas de forma contínua. Os dados experimentais foram expressos na forma de razão de umidade. O modelo de Page deteve o melhor ajuste para a cinética de secagem dos brotos da palma 'Gigante' e 'Miúda' minimamente processados, com os melhores coeficientes de determinação e qui-quadrado. Os modelos de Peleg e Wang & Singh não podem ser utilizados para simular o processo de secagem dos brotos da palma 'Gigante' e 'Miúda' dentro do intervalo de temperatura estudado, onde apresentam comportamento gráfico incoerente.

Quality and Drying Kinetics of Moringa (Moringa oleifera Lam.) Seed Flour After Drying Process

“…The parameters of the models adjusted to the experimental data of the water quantity kinetics during the drying of the moringa seed were verified the good representation of the Page model, which obtained the highest coefficients of determination (R 2 ), varying from 0,9197 to 0,9935 and the smaller chi-squares ( ), from 0,1618 to 0,2075 (Table 2). ISSN 2166-0379 2020 Pereira et al (2017a) These results show a good fit to the drying curve as presented in Figure 1, higher than that obtained by the other models. Considering the same criteria, we have the models of Henderson and Pabis (Fig 2) and Lewis (Fig 3) with good representation to the experimental points of the drying curve with R 2 above 0.82 and below 0,6 ( Table 1).…”

Aspectos tecnológicos na produção de farinha de polpa de pequi

“…Contudo, o modelo que melhor representou a secagem em camada delgada da polpa de pequi para as condições estudadas foi o modelo de Page (R 2 = 0,9999). O modelo de Page também apresentou bom ajuste aos dados experimentais de secagem da polpa de pequi da espécie Coriaceum (SOUSA et al, 2017) e do broto de pera espinhosa (PEREIRA et al, 2017) ambas secas em estufa nas temperaturas de 50, 60, 70 e 80 ºC, apresentando R 2 maior que 0,99.…”

Influence of power density and geometry of young cactus cladodes (Opuntia ficus-indica (L.) Mill.) on intermittent microwave drying kinetics

“…In the literature it can find values of k dec for nopal drying using different methods. The values reported by Díaz-Ayala et al (2015) for drying of thin slices of cladode with convective crossflow air were from 1.68 ×10 −4 to 5.75×10 −4 s −1 ; by Pereira et al (2017) for drying prickly pear shoots with forced hot air reported values from 1.77 ×10 −3 to 1.52 ×10 −2 s −1 . Thus, it can be observed that the values found in this work are within the range found in the literature.…”

“…The main advantages of drying are a decrease in feedstuff moisture and transport costs, inhibition of the growth of microorganisms, reduction of enzymatic and chemical reactions, and increased shelf life among others. In the literature, a different method of drying on cladodes has been reported: osmoticconvective (Medina-Torres, Gallegos-Infante, Gonzalez-Laredo, & Rocha-Guzman, 2008), forced convection tunnel (López et al, 2009), infrared drying (Touil, Chemkhi, & Zagrouba, 2014), convective transversal flow (Díaz-Ayala, Álvarez-García, & Simá-Moo, 2015), forced air circulation (Pereira et al, 2017), convective-vacuum (Dey et al, 2019). These studies have presented good results for considering drying as an appropriate method to preserve or transform cactus cladode.…”