Propriedades funcionais de frutas tropicais brasileiras não tradicionais.

Abstract

Fruits are generally an important source of antioxidant compounds. Brazil boasts a considerable diversity of tropical fruit species, of which the agroindustrial potential and nutritional value have not yet been established. The objective of the present study was to evaluate 18 non-traditional tropical fruits occurring in Brazil (acerola, assai, bacuri, camu-camu, carnaúba, cashew apple, gurguri, jaboticaba, java plum, jussara, mangaba, nance, murta, puçá-coroa-de-frade, puçá-preto, umbu, uvaia and yellow mombim) with regard to their potential for industrialization and consumption in natura, content of bioactive compounds and total antioxidant capacity (TAC). In addition, a subset of these fruits was evaluated for antioxidant dietary fiber (ADF) (assai, acerola and cashew apple) and oil quality (assai). Samples obtained from collections, crops or areas of occurrence were evaluated at the Laboratory of Physiology and Post-Harvest Technology (Embrapa Tropical Agroindustry, Fortaleza, CE, Brazil) for total soluble solids (TSS), total titratable acidity (TTA), TSS/TTA, pH, vitamin C, sugars, starch, pectins, anthocyanins, flavonoids, chlorophyll, carotenoids, polyphenols and TAC (fresh and dried matter) using four different methods (ABTS, DPPH, FRAP and β- carotene bleaching). Additionaly, at the Department of Metabolism and Nutrition (ICTAN-CSIC, Madrid, Spain) ADF was determined for samples of assai (BRS-Pará), acerola (BRS 236) and cashew apple (CCP 76), and TAC and oil quality were determined for assai (BRS-Pará). Each sample was tested with three repetitions and results were expressed as average values ± standard deviation. The functional properties of the 18 fruits evaluated varied significantly: most of the species may be considered good or excellent sources of bioactive compounds with high levels of TAC, especially acerola, camu-camu and puçá-preto, whereas assai, acerola and cashew apple contained 71%, 26% and 20% antioxidant fibers (AF), respectively. The association of high levels of TAC and AF makes assai an important source of ADF. Compared to extra-virgin olive oil, assai oil had higher TAC values and a similar composition of fatty acids (oleic and linoleic acids). The findings of this study may be helpful in identifying potential international markets for a range of relatively unexploited non-traditional tropical fruits