Proximate compositions, mineral contents and fatty acid compositions of native Amazonian fruits

Abstract

The proximate compositions, mineral contents and fatty acid compositions of different parts (peel, pulp and seeds) of 10 native Amazonian fruits were chemically characterized. The peel and pulp showed high moisture contents (43.13 to 94.03%), while the seeds showed greater levels of ash values, total crude protein and total carbohydrates (0.55–3.35%, 1.55–15.34% and 17.78–65.64%, respectively). High levels of total lipids (from 14.40 to 34.70%) were found in piquiá (pulp and almond), in 2 varieties of umari (peel and pulp), uxi pulp and biribá seed. A wide range of mineral contents was detected (Mn: 0.32–11.96mg/100g; Zn: 0.39–4.75mg/100g; Cu: 0.52–16.21mg/100g; Fe: 0.91–9.88mg/100g; Mg: 30.02–219.44mg/100g; Na: 2.76–350.56mg/100g; P: 4.52–382.64mg/100g). The highest mineral levels were found in the samples of bacuri-azedo pulp (Mn, Zn), cubiu small seed (Cu), piquiá outer peel (Fe), cubiu large peel (Mg), all pajurá parts (Na) and piquiá almond (P). Fatty acid analysis identified and quantified 32 fatty acids. The highest levels of palmitic acid (16:0) and oleic acid (18:1n-9) were found in the peels and pulps of the 2 varieties of umari and uxi and in the pulp and almond of piquiá, while the highest levels of linoleic acid (18:2n-6) and α-linolenic acid (18:3n-3) were found in the seed of biribá and pulp of uxi, respectively. All samples of peels and pulps, except for piquiá pulp, had n-6/n-3 ratio less than 4. The samples showed good varied proximal composition and mineral levels, each being rich in at least one nutrient. Monounsaturated fatty acids and polyunsaturated fatty acids were found in higher concentrations in most samples. Peels and pulps presented good n-6/n-3 ratios and are considered beneficial to human health.