Produção de bebida fermentada á base de extrato hidrossolúvel de soja adicionada de polpa de macaúba (Acrocomia aculeata (Jacq.) Lodd. ex Mart.) utilizando cultura láctea tradicional do iogurte e linhagem probiótica

Abstract

The objective of the present study was to develop fermented beverages based on water soluble soybean extract (EHS) with macaúba pulp (Acrocomia aculeata (Jacq.) Lodd. Ex Mart.) using traditional yoghurt milk culture and probiotic strain Lactobacilus acidophilus (LA-5). The macaúba pulp was characterized by the chemical composition, carotenoid content and total phenolic compounds. The antioxidant capacity in vitro was evaluated by the ABTS, DPPH and FRAP methods. Microbiological quality was determined according to ANVISA recommendations. In the production of fermented beverages, a traditional yoghurt culture composed of the species S. thermophilus and L. bulgaricus and a probiotic L acidophilus strain in the pure form and associated with the yogurt culture were used. In total, three base formulations of the EHS-based fermented beverage were produced and each of these divided into added and not added macauba pulp. After processing and packaging, EHS-based fermented beverages with and without macaúba pulp were stored for 28 days at 7 ± 1 ° C and evaluated for centesimal composition and monitored weekly (0, 7, 14, 21 ° and 28 ° day) in relation to pH, acidity and cell viability. The results showed that the macaúba pulp has adequate values of dietary fiber, proteins, lipids, carotenoids and phenolic compounds. The antioxidant capacity evaluated in the macaúba was around 7310.76 g fruit / g DPPH, 6.27 μM trolox / g fruit and 7.57 μM Ferrous Sulfate / g fruit for the DPPH, ABTS and FRAP methods respectively. The incorporation of macaúba pulp into the EHS-based fermented beverage increased the levels of all nutrients, with dietary fiber being the most significant component. Monitoring during refrigerated storage (7 ° C) showed that beverages fermented by traditional yogurt culture, added and not added to macauba pulp, maintained viable cell counts of about 7 log CFU / mL throughout the period evaluated with values maximum pH and acidity of 4.52 and 0.34%, respectively. In the L. acidophilus fermented beverages, the results demonstrated that probiotic viability declined 3 log cycles in the beverage without addition of pulp and 2 cycles in the added beverage, with final counts around 4 log CFU / mL. The values of acidity and pH were 0.33% and 4.47 (beverage without addition of pulp) and 0.34% and 4.52 (beverages with addition of pulp), respectively. In the fermented beverages where L. acidophilus was added along with the traditional yoghurt culture, the viability in both beverages with and without pulp decreased to reach 3 log CFU / mL. The values of pH and acidity remained constant in both, reaching final values of 4.61 for pH and 0.34% of acidity. As conclusion it is suggested that the use of macaúba pulp may contribute to the nutritional enrichment of all beverages, especially an increase of dietary fiber. The two dairy cultures used to ferment EHS, and the traditional yoghurt culture showed a higher fermentation rate and maintenance of the viable cells for 28 days, and the probiotic effect was observed until the 7th day in the final product.