Background: Vegetable proteins have widespread application in the food industry as functional
ingredients in food formulations according to the recent patents. Requirement to develop less expensive
protein-rich supplementary foods has resulted in shift of emphasis towards lesser known wild
than popular legumes.
Objective: The aim of this study is to expose seeds of two coastal sand dune wild legumes of the
Southwest India (Canavalia cathartica and C. maritima) to different doses of electron-beam (EB) irradiation
to assess changes in functional attributes.
Method: Intact dried seeds were exposed to EB irradiation (2.5, 5, 10, 15 kGy). Protein solubility, gelation
concentration, water-absorption capacity, oil-absorption capacity, emulsion properties and foam
properties of control and irradiated seeds were assessed by standard methods.
Results: Protein solubility of both seed flours attained the highest at 2.5 kGy, followed by gradual dosedependent
decrease. The gelation concentration increased in C. cathartica only at 5 kGy, while it decreased
in C. maritima at 2.5 kGy without further change at higher doses. The water-absorption capacity
of C. maritima was significantly higher than C. cathartica in control sample, while at 15 kGy C. cathartica
showed significantly higher absorption capacity than C. maritima. The oil-absorption capacity was
significantly higher in C. maritima than C. cathartica in control as well as all doses of irradiation.
Emulsion activity of C. maritima was slightly higher than C. cathartica in control and irradiated samples,
while both seeds showed similar emulsion stability in control with significant increase in C. cathartica
at 10 kGy and 15 kGy. The foam capacity in both seeds was similar up to 2.5 kGy followed by
significant increase in C. maritima at 5 kGy and 10 kGy. The foam stability was significantly higher C.
cathartica than C. maritima in control as well as in irradiated samples. The foam capacity was higher in
C. maritima than C. cathartica in control and irradiated samples, which showed gradual time-dependent
decrease in stability with higher stability at 8 hr in C. cathartica than C. maritima.
Conclusion: Improved functional properties (protein solubility, emulsion stability and foam capacity)
and decreased gelation concentration in seeds of C. maritima irradiated at 5 kGy is advantageous in the
production of functional foods. Even though both species of Canavalia grew on the coastal sand dunes
and their seeds were exposed to same doses of radiation, they differed in functional attributes confirm
that it is species-specific. Canavalia seeds being rich in proteins, carbohydrates, essential amino acids,
essential fatty acids and bioactive components, further studies on the impact of EB irradiation helps in
optimization of nutraceutical potential as well as functional attributes for future applications.