Processing as a strategy for the valorization and greater use of babassu mesocarp

Although edible, babassu mesocarp (BM) is considered a by-product of babassu nut oil processing. In addition, BM is rich in starch, minerals, bioactive compounds and antioxidant activity, characteristics that make it promising for functional food formulations. However, there are few studies evaluating the effect of BM processing, especially on the properties of the obtained flour. Thus, the objective of this study was to evaluate the effect of different processing methods on the physicochemical characteristics of babassu mesocarp flours (BMF). The flours were produced by four methods: convection drying (BMF-CD), cooking the fruits followed by convection drying (BMF-CCD), freeze drying (BMF-FD), and cooking the fruits followed by freeze drying (BMF-CFD). The BMFs were evaluated in relation to their physicochemical, mineral, bioactive, morphological, and structural characteristics. Based on the results, in general, no significant changes were observed in the proximal composition for the different BMFs, which had low protein and lipid content and high carbohydrate content, as well as high phenolic compounds content and high antioxidant activity. The obtained flour by freeze-drying (BMF-FD) had a higher total phenolic content (88.45^a mg GAE/g) and antioxidant activity by the ABTS method (878.6^a μmol TE/g). The flours obtained by pre-cooking the fruits had a higher iron content (BMF-CCD: 18.62^a mg/kg; BMF-CFD: 19.02^a mg/kg) compared to the flours produced without cooking (BMF-CD: 8.11^b mg/kg; BMF-FD: 4.09^b mg/kg). The increase in iron content can be attributed to the reduction of antinutritional compounds by cooking, since the cooked samples had lower tannin content (BMF-CCD: 30.40^d mg CE/g; BMF-CFD: 67.46^c mg CE/g), compared to flours produced without cooking (BMF-CD: 578.5^b mg CE/g; BMF-FD: 684.0^a mg CE/g). Pre-cooking of the mesocarp resulted in structural changes due to starch gelatinization, larger particle size (BMF-CCD: 274.4^a μm; BMF-CFD: 171.5^a μm), and lower crystallinity index (BMF-CCD: 2.56%; BMF-CFD: 0.45%), while the uncooked samples had smaller particle size (BMF-CD: 85.51^d μm; BMF-FD: 93.47^c μm) and higher crystallinity index (BMF-CD: 17.11%; BMF-FD: 16.60%).  It can be concluded that different processing methods modulate the properties of BMF, indicating that the choice of process can direct specific applications of BMF in food formulations. In addition, this study contributes to strengthening the understanding of unconventional food sources, reinforcing the potential of babassu as an ingredient for food formulation.