Frutos tropicais silvestres e polpas de frutas congeladas: Atividade antioxidante, polifenóis e antocianinas

Abstract

The tropical fruit juices are gaining ever greater space in the consumer market, and Brazil is one of the main producer countries in this market. There is a great diversity of products derived from fruits and new products for consumption are launched constantly, often without the necessary research into their active properties and beneficial activities to health. The objective of this work was to determine some properties of in natura wild tropical fruit and commercialized frozen fruit pulps. Considered as a method of great applicability, 2.2-difenyl-1-picrylhydrazyl radical (DPPH•) was used to determine the antioxidant activity; the Folin-Ciocalteu method was used to determine the total polyphenol concentration and the pH difference was used for anthocyanins. The fruit pulps of greater market consumption in Southern Brazil under analysis were mulberry, grapes, açai, guava, strawberry, acerola, pineapple, mango, graviola, cupuaçu and passion fruit, and the wild fruits were jambolão and baguaçu. When represented in TEAC (Trolox equivalent antioxidant activity), the global antioxidant activity of the frozen fruit pulps oscillated between minimal and maximal TEAC values of 0.5 and 53.2μmol g-1, or between 64.8 and 1198.9mg100 g-1 for VCEAC (vitamin C equivalent antioxidant activity) values. For the in natura fruit pulp extracts, TEAC oscillated between 13.3 and 111.2μmol g -1, and between 42.8 and 2533.1mg100g-1 for VCEAC. The descending order of antioxidant capacity was acerola> mango> strawberry> grapes> açaí> guava> mulberry> graviola> passion fruit> cupuaçu> pineapple. Among the wild fruits, baguaçu presents a greater antioxidant activity than jambolão.