Reduction of antinutrients and maintenance of bioactive compounds in flour from agro-industrial residue of acerola (Malpighia emarginata D.C.)

Abstract

This study was aimed at analyzing the reduction of antinutrients, preserving apparent phenolic compounds in acerola flour residue by employing drying techniques. The optimal drying conditions were then determined in the wet residue, analyzing antinutrient concentration and apparent phenolic compounds in the residue and subsequently in the acerola flour. The physicochemical characterization of the flour was carried out, determining its antioxidant activity, thereby assessing the impact of the drying process on the composition of volatile compounds. The optimal drying conditions were found for a temperature of 65ºC for 120 min, reducing water activity by 0.3 and moisture content by 13.89%, which are considered adequate conditions for flours. Carbohydrate content represented 68.72 g/100g, while proteins represented 12.55 g/100g of the centesimal composition of the flour. Significant reductions (p<0.5) of antinutrients were observed in saponins (35.9%), followed by phytates (32.8%) and condensed tannins (11.52%). Losses of 18.7% of apparent phenolic compounds were also observed. For volatile compounds, a significant loss of esters with a significant increase in alcohol content was noticed. Thermal processing reduced aroma complexity, but maintained important bioactive compounds, such as linalool and caryophyllene. In this regard, taking into account the results of the present study, the agro-industrial residue of acerola proved to be an alternative source of antioxidants with a reduced antinutritional impact and may be incorporated as an ingredient in the formulation of new food products. Moreover, this agro-industrial residue reduces the environmental impact caused by the fruit pulp processing industry.

Drying acerola residue in a spouted bed: Fluid dynamic study and functional quality analysis

“…Previous studies have explored using dried acerola residue in food formulations, such as pies, cakes, and meat products, and as a source of bioactive compounds for active packaging (Portugal Zegarra et al, 2018;Reinaldo et al, 2021;Rezende et al, 2018). Some studies have examined drying acerola residue using different devices, such as ovens with and without forced air circulation (Barros et al, 2020), tray dryers (Nóbrega et al, 2015;Tedesco et al, 2021), roto-aerated dryers (Silva et al, 2016), microwave ovens ( de Sousa et al, 2020), microwave-assisted rotary drums (Ramadan et al, 2019), infrared-assisted rotary dryers (Silva et al, 2021), radiation-assisted packed bed infrared (Nogueira et al, 2019), microwave vacuum dryers (Nogueira et al, 2023), fixed beds (Duzzioni et al, 2013;Silva et al, 2019), and thick-layer dryers (Silva et al, 2018).…”