Armazenamento de figo-da-índia em pó sob atmosfera controlada.

Abstract

The aim of this work was to obtain a prickly pear powder by the foam mat drying process and also evaluate the stability of the powder for 100 days of storage. The physical, chemical, physiochemical and microbiological characterization of the prickly pear pulp, formulation (emulsion), foam and the powder was made to achieve the results. The foam mat drying of the formulation, elaborated with the prickly pear pulp and additives, was made at 90 °C with layer thickness measured as 0.8 cm. Page, Henderson & Pabis and Cavalcanti Mata's models were fitted to the experimental data of the drying kinetics. The moisture adsorption isotherms of the powder at 20, 30 and 40 °C were determined. The stability of the powder, which was conditioned at laminated packing, was evaluated for 100 days of storage under controlled temperature and humidity. It was verified that the prickly pear pulp is of low acidity with low ascorbic acid content. The average drying time of the sample was of 220 minutes. The Page, Henderson & Pabis and Cavalcanti Mata's models were well-fit to the experimental data of drying. It was verified, during the storage of the powder, that the laminated packing didn't avoid the absorption of moisture; that the water activity increased and the reducers sugars decreased with time, and that the powder stored at 40 °C suffered darkening. The moisture adsorption isotherms were classified as being type III and the GAB, Peleg and Oswin models can be used to estimate the data.