Influence of Drying Treatment on Physical Properties of Pumpkin

• Author(s): Henriques, Francisca ; Guiné, Raquel ; Barroca, Maria João
• Date: 2012
• Persistent ID: http://hdl.handle.net/10400.19/1120
• Origin: Repositório Científico do Instituto Politécnico de Viseu
• Subject(s): pumpkin; freeze drying; colour; drying; texture
• Document Type: Article
• Language: English

Description

The aim of this work was to evaluate the properties of pumpkin (Cucurbita maxima L.) exposed to convective air drying and freeze-drying. The samples were analyzed in terms of physical properties (colour and texture). The trials in the convective chamber were done at 40 ºC and 60 ºC, in the drying tunnel at 60 ºC and in the freeze dryer at -50 ºC. It was concluded that the freeze drying and the air drying at 40 ºC produced smaller changes in the colour while the drying in the tunnel originated more intense colour changes. With respect to texture, it was possible to deduce that the pulp in the fresh product at 2 cm off from the skin is harder than the pulp at 4 cm off from the skin. As to the effect of drying in the texture of the pumpkin, it was observed that all dryings affected texture considerably when compared to the fresh product. In fact, hardness varied from 75 % in the drying in chamber at 40 ºC to 90 % in the tunnel drying, when compared to the fresh product. As to springiness, it was changed more in the drying at 40 ºC, while cohesiveness showed the higher change in the freeze drying treatment.