4 CONCLUSIONS
The present study investigated the effect of treating canola meals (CP
or HE) with SSF by A. niger and A. oryzae on the
functionality of extracted protein products (AE-IP or SE). In summary of
the findings, protein purity in the resulting isolates was negatively
influenced by fermentation, and the magnitude of reduction was greater
for AE-IP products than SE. The protein content was also lowered in the
presence of residual fat in the CP samples compared to HE when the
protein products were produced by AE-IP. There were significant
differences in canola protein functionalities extracted from fermented
meals compared to the controls. For AE-IP proteins, meal fermentation
had an overall negative effect on solubility however some improvements
were seen with A. niger fermentation. Pretreatment with A.
oryzae increased the protein solubility at pH 7 when extracting
proteins via SE. Grouped together, the SE protein products were more
soluble than those by AE-IP, while those extracted from CP meals showed
higher solubility than those from HE. Fermentation of the meals improved
the WHC and OHC of most protein products with strain difference most
evident in SE proteins from HE meals. For emulsifying properties, the
strain A. oryzae was shown to enhance or maintain the EAI of the
isolates more effectively than A. niger , whereas ESI was largely
unchanged upon fermentation, regardless of the strains; the AE-IP
prepared isolates responded more positively to SSF than those by SE.
Foaming properties at pH 3 and 5 were generally diminished by SSF while
some increases at pH 7 were observed. A. niger was slightly
preferred over A. oryzae to improve or minimize the decreases,
while the CP products, control or fermented, tended to foam better than
those processed by HE. In short, no overarching trend could be reported
for the effect of meal fermentation on the resulting functionalities of
extracted canola proteins, as most functional attributes were under the
combined influence of pH, test strains, and oil and protein extraction
techniques. However, the findings indicate that by modifying processing
conditions, functionalities of canola meal protein products could be
tailored accordingly to suit potential applications, and SSF by A.
niger and A. oryzae remains a promising practice to expand the
utilization of canola proteins.