Chemical Properties of Pumpkin Dried by Different Methods

Cucurbitaceae (Cucurbits) family includes around 825 species, derived from tropical and subtropical regions, including 26 species that are cultivated as vegetables. In tropical regions the consumption of cucurbits is very high and it has an important role in human consumption (Almeida, 2006). The main crops are pumpkins, watermelon, cucumbers and melons. Pumpkins are rich in water, vitamins, antioxidants and carotene (provitamin A) that protects the body and prevents the premature aging (Canico et al, 2005), although this is particularly true if it comes from orange fruit pulp. Pumpkins are also poor in total solids (Alibas, 2007) and in calories, which means that they are adequate for low calories regimes, and they are often recommended in diets. This vegetable is also known for the properties of its seeds, that are rich in fat, protein, thiamin, niacin and various minerals (Almeida, 2006), and when crushed provide a pulp with medicinal power which acts as anti-infl ammatory, diuretic and emulsifi er that helps in fever treatment, ear pain, infl ammation of the urinary and prostate disorders (Cunha, 2003). Pumpkin, like most vegetables, is a perishable food whose characteristics are changed with time. Therefore it becomes necessary to use conservation methods that allow preserving its properties. One of the most commonly used methods for conservation is drying, which is considered the oldest and the most important method of food preservation (Sacilik, 2007). This process consists of removing water from the product in order to reduce the water activity and as a consequence minimize the microbiological changes (Krokida et al, 2003) or enzymatic reactions (Harbour et al, 2009). Furthermore, it originates a considerable reduction in weight and volume, minimizing packing, storage and transportation, as well as allowing storage of the product without refrigeration (Guine, 2008). During drying many changes occur in the food, such as structural and chemical modifi cations, that affect the fi nal product quality. Furthermore, it can cause signifi cant loss of some compounds which have importance at the functional level (Maskan, 2001).