Brazil Nut (Bertholettia excelsa H.B.K.) Brown Skin Characterization - a Waste Product Generated from Shelled Dry Nut Factories of Amazon Region

We report the characterization of the Brazil nut brown skin, that is located between the nut shell and edible part and its possible application as Se supplement in Se poor diets . Brown skin is produced, after the autoclaving and shelling processes in the factories of shelled dry nuts, and is discarded as waste. The skin samples were collected from two factories of different Amazon regions and evaluated for their cell structures by scan electron microscopy (SEM), Se levels by atomic emission spectrometer with inductively coupled plasma (ICP), antioxidant activity by TEAC (trolox-equivalent antioxidant capacity) and FRAP (ferric reducing ability of plasm), its composition (in lipids, proteins, carbohydrates, and fiber) and safety (moisture content, water activity, fungi, bacteria and aflatoxins). SEM allowed the visualization of brown skin structures with highly fibrous, lignified tissues, thick walls with amorphous shape cells of the rough and smooth skin surfaces. Se levels had a significant variation for the two Amazon regions points of collection (6.34 and 20.58 mg/kg, for Cameta/Eastern and Manaus/Central-Western factories, respectively). The proximate composition presented quite high fiber content (59.92 and 60.10 %) with low lipids and protein (15.92/16.02; 8.79/9.07 %) percentage though. Due to the high Se and fiber content, apart from the safe parameters data obtained, the currently discarded brown skins showed their utilization potential to be used either as Se supplement and/or to be included into the low fiber/Se content diets. Two preliminary supplement capsules of Se with the skins of both Amazon regions were developed.