Secagem da cenoura (Daucus carota L.) pelo método foam-mat

• Autor(a) principal: Delmiro, Thalita Marreiro
• Data de Publicação: 2016
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Institucional da UFRN
• Texto Completo: https://repositorio.ufrn.br/handle/123456789/38924
• topic: cenoura; secagem; foam-mat; carrot; drying; Engenharias.

The carrot (Daucus carota L.) is a tuberous root belonging to the family Apliaceae. This vegetable has an important nutritional value, since it has in its composition, several components responsible for maintaining the good balance of the body (potassium, magnesium, copper, calcium and phosphorus), as well as complex B vitamins, which are important for the regulation of nervous system and digestive system. In addition, the carrot is also known to present a large amount of carotenoids. Among them the one that receives the most attention is β-carotene, because it has a greater pro-vitamin A activity. As for carrot consumption, the main form is in natura, however it has been evident in recent years the use of the carrot in the form minimally processed or as an enriching source of food product formulations. Carrots, like all vegetables, have a high moisture content, which makes it a product with a small shelf life. Therefore, drying becomes an alternative to increase the usefull life of this vegetable. In this perspective, the objective of this study was to evaluate the technical feasibility of drying the carrot by the method of foam layer or foam-mat, using Emustab 2.5% emulsifying agent. This ratio was defined from carrot foam expansion tests, which had a value of approximately 193% of expansion, for a beat time of 10 min. Dryings of the carrot foams were conducted at temperatures of 60, 70 and 80°C, for masses of 200, 250 and 300 g of foam. The drying kinetics obtained for each experiment demonstrated a long period of constant rate followed by a period of decreasing rate. These data were adjusted to Fick's diffusional model and the Page’s model, the latter with a good fit, presenting a correlation index higher than 0.99. Both the effective diffusivity and the specific drying rate K of the Page model increased with the drying temperature, whereas for the same temperature, larger drying masses guaranteed a greater value of effective diffusivity and lower K. In relation to the period of constant rate, drying rates between 0.8811 and 1.7582 g / min were obtained. As for the physicochemical analyzes, in general a reduction of the pH and of the total soluble solids of the reconstituted dry product was observed in relation to the unprocessed foam. The titratable total acidity did not show significant variations. The hygroscopicity was between 22.18 and 27.97% and the solubility was between 62.87 and 70.43%.