3.1. Carbohydrase treatments
Table 2 summarizes the effectiveness of various carbohydrases on
the total oil and protein extraction yields, defined here as the oil and
protein recovered from initial dehulled yellow mustard flour during
carbohydrase-assisted aqueous extraction processes. The aqueous processing
of dehulled yellow mustard flour without the assistance of
carbohydrase (control) resulted in the oil and protein extraction
yields of 55.5% and 60.7%, respectively. Celluclast 1.5 L is a cellulase enzyme,
Pectinex Ultra SP-L is a pectinase enzyme with limited cellulase
and hemicellulase activities, and Viscozyme L is a multi-enzyme complex
containing a wide range of carbohydrases, including arabanase,
cellulase, beta-glucanase, hemicellulase, and xylanase (Novozymes,
product data sheet). Although, the individual use of all of the three commercial
carbohydrases represented significant improvement (P b 0.05)
in the oil extraction yields, Celluclast 1.5 L and Viscozyme L were more
effective by increasing the oil extraction to around 67%, indicating that
the breakdown of cellulose was certainly beneficial to the release of
oil into the aqueous medium. While Celluclast 1.5 L was able to facilitate
the oil yield, it was a relatively inefficient way to improve protein
extraction yield, compared with Viscozyme L and Pectinex Ultra SP-L.
Therefore, these commercial carbohydrases were combined to evaluate
their collaborative effects on the oil and protein extractabilities. The
outcomewas encouraging as all the yieldswere further increased, especiallywith
a combination of three enzymes in Run 6,where 76.3% of the
oil in theflourwas extracted alongwith 74.9% of the proteins, indicating
more efficient hydrolysis of the yellow mustard cell wall polysaccharides
by the combination of carbohydrases.