INFLUENCE OF PROCESSING PARAMETERS ON BIOACTIVE COMPOUNDS OF CAFERANA SEEDS (BUNCHOSIA GLANDULIFERA)

Bunchosia glandulifera is a species popularly known as caferana, ciruela or false guarana. Traditionally, its seeds are roasted, grounded, and consumed similarly to guarana powder (Paullinia cupana). High roasting temperatures over a long period may cause degradation and/or modifications in phenolic compounds, amino acids, and polysaccharides resulting in a product with a bitter taste. However, short roasting periods can generate incomplete chemical reactions impairing at the bioavailability of the compounds and the flavor of the product. The objective of this study was thus to evaluate the roasting process of caferana seeds by varying the time and temperature. A Central Composite Rotatable Design (CCRD) was performed from 147 to 168 °C and from 27 to 84 min respectively, distributed in 11 trials. Samples were characterized concerning their residual moisture content, total phenolic compounds (TPC) by Folin-Ciocalteu, antioxidant activity (AA) by the DPPH method and total caffeine content. Results revealed that the binomial time/temperature had a direct influence on the moisture content that varied between 0.61 and 2.71%. The roasting time inversely affected the TPC, which varied from 376.58 to 940.20 mg/100g of powder. AA ranged from 15.59 to 104.45 gpowder/gDPPH. The Pearson correlation between AA and TPC presented an index of -0.86, showing that the correlation is inversely proportional. For the caffeine, the values obtained were between 1108.40 and 2683.16 mg/100g of roasted powder. Considering the individual parameters, higher temperatures led to higher caffeine content, whereas longer roasting time caused a lower value. Nevertheless, the time/temperature interaction had significance at the level of p=0.5. Best results in terms of bioactive compounds content were reached at 158 °C and 27 min of roasting.