Evaluation of red cabbage anthocyanins after partial purification on clay

The aim of this work was to evaluate the red cabbage anthocyanins quality after purification by static adsorption assays on clay (Tonsil Terrana 580FF). Thin-layer chromatography analysis and scan spectrometry on UV-Visible showed a good dye stability of the pigment interacting with the clay. The use of pH 3.0 buffer during the batch assays provided a protective effect on the cabbage anthocyanins, limiting the dye acid hydrolyses. Analyses of the reducing sugars contents of the extract showed that clay retained 20 percent average of total free sugars under the test conditions.

Extraction of red cabbage anthocyanins: optimization of the operation conditions of the column process

The aim of this work was to extract anthocyanins from the red cabbage. Batch studies under several extraction conditions indicated that acetic acid in aqueous solution (10 percent V/V) was the best solvent, used in the proportion of 0.25 g of red cabbage mL-1. At this condition, column assays were carried out to evaluate the influence of the ionic force, pH, solvent flow rate, recirculated volume of red cabbage juice and the mass of red cabbage. Results showed that the pH, recirculation and mass of red cabbage had statistically significant effects, where the optimum operation conditions found for the process were pH 2.3, recirculation volume of the solvent 0.83 L and mass of red cabbage 50 g.

Desde os primórdios dos tempos as antocianinas são extraídas de vegetais, mas avanços que garantam um processo viável e rentável exigem conhecimento, quantificação e controle das condições de operação. Estudos em batelada sob várias condições de extração indicaram que ácido acético em solução aquosa (10 por cento V/V) foi o melhor solvente, quando usado na proporção de 0,25 g de repolho roxo mL-1. Nesta condição de operação foram feitos ensaios em coluna para avaliar a influência da força iônica, pH, taxa de escoamento do solvente, volume recirculado da solução de extração e massa de repolho roxo. Os resultados mostraram que o pH, recirculação e massa de repolho foram estatisticamente significativos, e as condições ótimas de operação encontradas para o processo foram pH 2,3, volume de solvente recirculado de 0,83 L e massa de repolho roxo igual a 50g.

Matérias estranhas em erva-mate(Ilex paraguariensis St Hil) beneficiada no estado de Santa Catarina, Brasil / Extraneous material in mate(Ilex paraguariensis St Hil) industrialized in Santa Catarina state, Brazil

A erva-mate (Ilex paraguariensis St. Hil.), um produto bastante consumido na região Sul do Brasil naforma de chimarrão, foi avaliada quanto à sua qualidade para o consumo. Foram feitas análises paradetecção de matérias estranhas e presença de cristais de açúcar (microscopia), microbiológicas e atividadede água. Fragmentos de insetos, ácaros, e pêlos de roedor, classificados como sujidades leves, foramrecuperados das amostras de erva-mate de duas regiões do estado de Santa Catarina: norte e oeste. Asanálises microscópicas também detectaram a presença de cristais de açúcar (sacarose) em duas amostrasda região oeste, indicando fraude, pois este componente não estava declarado na lista de ingredientes darotulagem. A análise de coliformes fecais estava de acordo com a legislação vigente e a atividade deágua apresentou valores abaixo de 0,6.

The quality of Maté (Ilex paraguariensis St. Hil.), a highly consumed beverage in Southern region of Brazil as an especial infusion called “chimarrão”, was evaluated. Extraneous material occurrence, sugar crystals presence, microbiologic analysis , and water activity testing were performed. Insects and mites fragments, and rodents’ hairs were recovered from samples from both North and West regions of Santa Catarina state. Microscopy analysis also detected sugar crystals (sucrose) in two samples from Western region, indicating fraud of the product as for sugar was not included in the ingredients list label. Fecal coliforms analysis was in accordance with Brazilian legislation (Anvisa standards), and the water activity measurements were lower than 0.6.

Adsorption of natural dyes on clay fixed on polymers

The main purpose of this work was to produce a pellet to minimize undesirable effects in fixed beds, such as colmatation, through clay fixation on the surface of polymeric particles. Preliminary experiments were carried out by heating the clay, namely Tonsil Terrana 580FF, in order to observe variations on its capacity to adsorb anthocyanins derived from red cabbage. Clays was fixed on five samples of high density polyethylene (HDPE) at 180°C -210°C for two hours. The morphological analyses of the resulting particles were accomplished through Scanning Electron Microscopy (SEM). The experiments demonstrated an increase on clay's adsorptive capacity of 15.65 percent at 120°C for 30 hours and 16.80 percent at 170°C for two hours. The SEM analysis showed that the clay particles adhered on the external surface of the pellets .These results show that it is possible to obtain polymeric pellets using HDPE coated with clay.