The oil of the açai palm tree (Euterpe oleracea) fruits has a beneficial lipid profile for health with a high content of mono and polyunsaturated fatty acids, besides antioxidant substances, which provides its appreciation on the industry. The aqueous extraction of vegetable oils supported by enzymes has been widely used because of its benefits compared to the traditional processes. In this context, this work aims to identify the best combination of enzymatic preparations, which would maximize the aqueous extraction yield of the oil of the açai palm tree fruits from the pulp. The açai pulp was obtained from fruits collected in Abaetetuba during the 2015 crop. Four commercial enzymatic preparations (Novozymes) were used: Celluclast 1,5L (cellulase); Viscozyme L (endo 1,3(4) β-glucanase, xylanase, cellulase and hemicellulase); Ultrazym AFP (pectin lyase, cellulase and polygalacturonase); and Shearzyme 500L (endo 1,4-xylanase). The tests of açai oil extraction were performed by a process developed in this work with the following parameters: mean granulometry of the açai pulp of 0,75 cm; global dry matter of the aqueous mixtures of the pulp of 15%; individual enzymatic concentration of 1% (w:w) on pulp basis; constant orbital agitation of 100 rpm and vigorous agitation by hand every 30 minutes; incubation time and temperature of 4 hours and 50°C, respectively. The enzymatic preparations were tested individually (1x1) in quadruplicate, or combined (2x2; 3x3 and 4x4) in triplicate, totaling 89 tests. The negative control presented a mean yield of extraction of 34,91±11,81%, the lowest of all the tests. The tests performed with the isolated enzymatic preparations have enabled an increase of the extraction yield up to 36,66% compared to the negative control, confirming the important role of the enzymes in the aqueous extraction process. The tests performed with the enzymatic preparations combined 3x3 and 4x4 have increased the extraction yield up to 99,05% compared to the negative control, demonstrating the importance of using the combinations of enzymatic preparations. Among the different tests performed, the enzymatic preparations that stood out are Celluclast 1,5 L, Viscozyme L and Ultrazym AFP by facilitating the oil recovery with a reduce standard deviation (±3,01%). Furthermore, the extraction yield using this combination of three enzymatic preparations is statistically equal to the extraction yield using the four enzymatic preparations, which becomes interesting to the industry due to the cost reduction in the process.
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