Is Your Açaí Really from Amazon? Using DNA Barcoding to Authenticate Commercial Products

Acai is an Amazon superfruit with antioxidant and anti-inflammatory properties used in the preparation of energy drinks consumed mainly in Brazil and lately exported to the whole world. It is obtained from two palm species, Euterpe oleracea (mainly) and Euterpe precatoria (secondarily). However, it may be mistaken with the fruit of a non-Amazon sister species (Euterpe edulis), called jucara, due to its morphological similarities. As species identification is fundamental in the confirmation of commercial product authenticity, and most of the time the morphological identification is impossible, the molecular biology analysis represents a powerful method in food science. DNA barcoding, for example, represents an efficient method for detecting plant-based adulterants. In this study, we established a DNA barcoding method for discriminating the three Euterpe species, and it was successfully applied to authenticate acai commercial products sold in the Brazilian market. After testing nine regions as DNA barcoding candidates in reference samples, psbK-I region was elected for the authentication method. As result, 88.6% of the samples were classified as authenticated and 11.4% were classified as adulterated products. Authenticated acai products showed clustered with E. oleracea reference plants. Four adulterated acai products showed clustered with E. edulis, a different species from the label. No products showed clustered with E. precatoria. These results bring us concern about the correct identification of species in food and about the occurrence of misleading advertising on labeled acai products.