The Mechanism of Extraction of Peanut Protein and Oil Bodies by
Enzymatic Hydrolysis of the Cell Wall
Degradation of the peanut cell wall is a critical step in the aqueous
enzymatic extraction process to extract proteins and oil bodies.
Viscozyme® L, a compound cell wall degrading enzyme, has been applied as
an alternative to protease in the process of aqueous enzymatic
extraction, but the mechanism of cell wall enzymolysis remains unclear.
The present study aims to investigate the changes in cellulose,
hemicellulose, and pectin content of the peanut cell wall hydrolyzed by
Viscozyme® L. The degree to which the main components of the peanut cell
wall, such as trans-1, 2-cyclohexanediamine-N,N,N’,N’-acetic
acid-soluble pectin (CDTA-soluble pectin), Na2CO3-soluble pectin,
cellulose, and hemicellulose, are degraded is closely related to the
extraction of oil bodies and peanut protein at different solid-liquid
ratio of powered peanut seed in distilled water, enzyme concentration,
enzyme hydrolysis temperature, and enzyme hydrolysis time. The key sites
of Viscozyme® L activity on cell wall polysaccharides were explored by
comparing the changes in chemical bonds under different extraction
conditions using Fourier-transform infrared spectroscopy (FT-IR)
absorption bands and principal component analysis (PCA). Viscozyme® L
acted on the C-O stretching, C-C stretching, and CH2 symmetrical bending
of cellulose, the C-O stretching and O-C-O asymmetrical bending of
hemicellulose, and the C-O stretching and C-C stretching of pectin.