Nutritional value in processed products of acai (Euterpe precatoria), An amazonian fruit

Acai is a Brazilian palm tree which fruits are widely used by the Amazonian population and play an important socioeconomic and cultural role. Knowledge of food compositional, nutritional and functional properties is fundamental for defining the quality of tropical fruits – characterized by both the abundance and bioavailability of essential nutrients. This study is aimed to evaluate the composition of water, proteins, lipids, carbohydrates, fiber, caloric content, and the minerals calcium, iron, magnesium, manganese, potassium, sodium, zinc and copper in acai products – pulp, jam and jelly. The samples of these products were lyophilized until complete dehydration to estimate the humidity percentage. The protein content was estimated based on the total content of nitrogen of the samples in natura by the Kjeldahl method. The determination of the lipid content was carried out by extraction in a Soxhlet with acid hydrolysis. The portion of carbohydrates was determined by subtracting the weights of water, proteins, lipids and ashes from the original sample. The analysis of the dietary fiber was based on digestion in an acid medium followed by digestion in an alkaline medium. The energy content of each product was estimated from the content of proteins, lipids and carbohydrates. In order to determine the content of minerals, the samples were calcinated and acidified in an open system and then quantified by flame atomic absorption spectrometry. The content of nutrients and caloric content found in the study were compared to the Daily Reference Value (DRV) established by the Ministry of Health based on a daily diet of 2,000 kcal for healthy adults. Water, protein, lipids, and fiber were higher in pulp than in jam and jelly. Carbohydrates and caloric content was higher in jam. Minerals were higher in pulp. The higher nutrient concentrations in pulp indicate that the processing, especially cooking, leads to loss of nutrients. An exception was observed for carbohydrates and energy content, because of the inherent addition of sugar in the production of jam and jelly.