ABSTRACT
Objective: To establish the common model of four kinds of rattan traditional Chinese medicinal materials (TCMM) (Paederiae Scandens Caulis, Lonicerae Japonicae Caulis, Polygoni Multiflori Caulis, and Ipomoea batatas Caulis) determinate the drying kinetic parameters, and study the stability of active ingredients in the drying process. Methods: The experimental data of four rattan TCMM were fitted to the nine thin layer models (Page, Wang and Singh, Two-term exponential, Newton, Logarithmic, Aghbashlo, Two-term, Midilli, Diffusion approach) at the temperature of 40, 50, 60, and 70 ℃. R2, χ2, and RMSE were used as the criterion of fit. Fick diffusion law was used to calculate the drying dynamical parameters. Based on the principle of chemical kinetics, the stability of active ingredients in the drying process was studied. Results: Aghbashlo model was the best one to describe drying process of four rattan TCMM. The effective moisture diffusion coefficients D and activation energy Ea of four rattan TCMM were between 1 × 10−10 and 1 × 10−9 m2/s and 40—50 kJ/mol respectively. The degradation reactions of ursolic acid, THSG, and polysaccharide conformed to the first-order kinetic equation. The content of chlorogenic acid increased with the drying temperature and drying time increased. Conclusion: The drying dynamical parameters values of TCMM with different parts have different ranges, their drying process should be described by a common model. The quality of TCMM was affected greatly by drying process.
ABSTRACT
Se caracterizó la composición química y las propiedades físicas y reológicas de la harina y almidón, ambos obtenidos de la pulpa comestible de la batata (Ipomoea batatas Lam), a fin de mostrar el potencial de estos derivados como ingredientes en la formulación de productos alimenticios. Para lograr este objetivo, se evaluaron los siguientes parámetros: rendimiento y eficiencia de la extracción, composición proximal, contenido de amilosa, azúcares totales, azúcares reductores y no reductores, contenido de minerales, índice de absorción de agua (IAA) y de solubilidad en agua (ISA), separación de fases, pH, acidez titulable, parámetros reológicas y color. Se obtuvo una harina con un buen potencial nutricional: alto contenido de carbohidratos totales (59,80 por ciento) y con relativo aporte de fibra dietética total (7,33 por ciento) y fósforo (21,92 mg/100 g) a través de un proceso muy eficiente (97 por ciento). Asimismo, se obtuvo un almidón de alta pureza (99,25 por ciento), con relativo bajo contenido de amilosa aparente (16,40 por ciento). Los resultados mostraron diferencias significativas (p 0,05) en las propiedades reológicas del almidón, comparadas con las de la harina. Tanto el almidón como la harina presentaron características para ser usados en la industria de alimentos como ingredientes en una gama de productos alimenticios, tales como productos horneados, mezclas para tortas, mezclas para sopas y pastas de untar, entre otros.
This study characterized the chemical, physical and functional properties of the flour and starch obtained and starch isolated from the edible portion of sweet potato (Ipomoea batatas Lam). In order to fulfill the objectives, the following parameters were evaluated: extraction efficiency and yield, proximal composition, total sugar , reducing and non reducing sugars, starch and its relative amylose content, pH, titratable acidity and absolute density; water absorption index (WAI) and water solubility index (WSI), phase separation, rheological properties and color. Results pointed out that both highly pure starch (99.25 percent) and good nutritional quality flour may be easily obtained from sweet potato, with high total carbohydrate content (59.80 percent), and a relatively good dietary fiber (7.33 percent) and phosphorous (21.92 mg/100g) contents. Statistical significant differences (p<0.05) in the rheological properties of the starch and flour were also registered. Both starch and flour have excellent potential as ingredients for new product development.