Siebert_2021_J.Sci.Food.Agric__

BACKGROUND: The use of rapeseed protein for human nutrition is primary limited by its strong bitterness which is why the key bitter compound kaempferol 3-O-(2'''-O-sinapoyl-beta-sophoroside) was enzymatically degraded. RESULTS: Mass spectrometric analyses of an extract from an untreated rapeseed protein isolate gave three signals for m/z 815 [M-H]. The predominating of the three compounds was confirmed as kaempferol-3-O-(2'''-O-sinapoyl-beta-sophoroside). Enzymatic hydrolysis of this key bitter compound was achieved using a sinapyl ester cleaving side-activity of a ferulic acid esterase from the basidiomycete Schizophyllum commune (ScoFAE). Recombinant ferulic acid esterases from Streptomyces werraensis (SwFAE) and from Pleurotus eryngii (PeFAE) possessed better cleavage activities towards methyl sinapate, but did not hydrolyse the sinapyl ester linkage of the bitter kaempferol sophoroside. CONCLUSION: Kaempferol-3-O-(2'''-O-sinapoyl-beta-sophoroside) was successfully degraded by enzymatic treatment with ScoFAE, which may provide a means to move the status of rapeseed protein from feed additive to food ingredient. This article is protected by copyright. All rights reserved.