Edible Seeds and Nuts Grown in Brazil as Sources of Protein for Human Nutrition

Abstract

Edible seeds and nuts can contribute to an adequate intake of protein, particularly in vegetable-based diets. However, there are relatively few reports with insufficient data regarding the protein quality of these foods, especially of edible seeds and nuts from Brazil. The aim of this study was to investigate the chemical composition and in vivo protein quality of two edible seeds (baru almond and peanut) and two nuts (Brazil nut and cashew nut) grown in Brazil. The proximate composition and the amino acid profile were analyzed. The true protein digestibility and the protein quality of these foods were evaluated by bioassay with male weanling Wistar rats over a period of 14 days, and the Protein Digestibility Corrected Amino Acid Score (PDCAAS) was estimated. Edible seeds and nuts presented high contents of proteins (16.3 to 32.3 g/100g), lipids (42.7 to 57.9 g/100g) and dietary fibers (6.5 to 14.3 g/100g). Lysine was found to be the limiting amino acid in baru almond, peanut and Brazil nut, which had amino acid scores ranging from 71% to 76%. Cashew nut had no limiting amino acid. These foods showed high protein digestibility (around 90%) except for baru almond (75%), and their PDCAAS values varied significantly (57%, for baru almond, and 90%, for cashew nut). The edible seeds and nuts grown in Brazil provide a high density of energy and nutrients and they can be used as complementary sources of proteins.