ULTRASOUND-ASSISTED PROTEIN EXTRACTION FROM DEFATTED PEANUT FLOUR (ARACHIS HYPOGAEA) FOR LIQUID AMINOS PRODUCTION

Abstract

Defatted peanut flour, the primary byproduct of peanut oil processing, is a rich precursor for umami peptides due to its high content of acidic amino acids, which play key roles in umami taste formation. In this study, protein from defatted peanut flour (DPF) was extracted using ultrasound-assisted extraction (UAE) and applied to liquid aminos production. The effects of key technological parameters were evaluated, establishing the optimal extraction conditions as follows: a solid-to-solvent ratio of 1:15 (w/v), pH 12, an extraction temperature of 80 °C, and an ultrasonication duration of 20 min. Under these optimized conditions, the protein recovery yield reached 87.00 ± 7.21%. The resulting protein extract was subsequently hydrolyzed using Protease A (1% w/w) at 60 °C for 4 h. The final total nitrogen (TN) and amino acid nitrogen (AAN) contents were 4.69 ± 0.02 g/100 mL and 1.134 ± 0.02 g/L, respectively. These findings demonstrate that DPF, owing to its high protein content, serves as a promising raw material for high-quality liquid aminos production.