According to the official MonaVie website, they are purveyors of a juice blend that contains white grape, pear, acerola, pear puree, aronia, purple grape, cranberry, passion fruit, banana, apricot, prune, kiwi, blueberry, bilberry, camu camu, wolfberry, pomegranate, lychee fruit, açaí, and palm nut oil. While MonaVie will not disclose the percentage of açaí in their products, they tout them as premier açaí blends — under the implication that a large percentage of the juice blends is açaí.
Ever seen an açaí berry? Neither had I. The berries are produced by a palm tree known scientifically as Euterpe oleracea, common along Brazil’s Amazon River; almost all the açaí palms grow wild in deforested floodplains. When ripe, the berries are dark purple, about the size of a blueberry, and contain a thin layer of edible pulp surrounding a large seed. During the dry season when the fruit is plentiful, hundreds of men lug woven baskets filled with the shiny fruit plucked from the 80-foot-high palm trees that line the river. Demand is high for the staple of native Amazon cuisine, virtually unknown globally until 15 years ago when a pair of Californians recognized the economic potential of the regionally popular berry.
Along with the moniker as a “super food”, açaí berries are highly regarded for their amounts of antioxidants. A 2006 Brazilian study of antioxidants in the most commonly consumed fruits in Southern Brazil (mulberry, grapes, açaí, guava, strawberry, acerola, pineapple, mango, graviola, cupuaçu, and passion fruit) concluded that the highest levels of Trolox-equivalent antioxidant capacity (TEAC) were found in acerola (53.2 μmolg-1 (micromoles of Trolox equivalents per gram)), mango (12.9), strawberry (9.2), grapes (7.0), and açaí (6.9). A similar 2004 study by the USDA among fruits common to the United States indicated total (lipophilic and hydrophilic) oxygen radical absorption capacity (ORAC) of cranberries (94.56 μmolg-1 (micromoles of Trolox equivalents per gram)), wild blueberries (92.60), plums (62.39), and blackberries (53.48). An article in the Journal of Agricultural and Food Chemistry reported the ORAC of freeze-dried fruit pulp and skin powder of açaí berries as 1027 μmolg-1 (micromoles of Trolox equivalents per gram), the same value used in marketing by MonaVie. While the studies used different assays (TEAC vs. ORAC), the measurements are 98% correlated in the above antioxidant studies due to the high capacity values (above 8 μmol/L (micromoles of Trolox equivalents per Liter)), after taking the length of the inhibition time into account.
What this means to the average non-scientist is that eating six to eight large strawberries (about 1/4 pound) or a few mango slices (about 1/6 pound) results in the same antioxidant potential as a one-gram pill of pure, concentrated, freeze-dried açaí berries or 1/3 pound of fresh açaí berries. Modern processes have been able to concentrate antioxidants per gram from açaí berries to the highest level of all fruits, but whole açaí berries are much farther down the scale than other readily available fresh fruits. With a vast number of juices and supplements competing for consumers’ money, it makes good business sense to tout ingredients with the highest measurable numbers — thus the trend towards using freeze-dried açaí berries instead of purees and pulps; the number 1027 sounds a whole lot better than 6.9.
Are açaí berries a good source of antioxidants? Yes. But if it’s only the amount of antioxidants you care about, the same USDA study points to other non-fruit sources of antioxidants such as pecans (179.4 μmolg-1, or about 1/2 a nut to compare to the one-gram açaí pill), dried oregano leaf (2001.29, or about half a leaf), and cinnamon (2675.36, or 1/10th of a teaspoon). At the top end of the scale, a single drop of clove essential oil has an ORAC score of 10,786,875 μmol/L, the same amount of Trolox-equivalent antioxidants as in several spoonfuls of freeze-dried açaí berry powder.