The levels of bioactive compounds found in raw and cooked Canadian pulses.

The effect of cooking on the levels of bioactive compounds (oligosaccharides, polyphenols and saponins, and vicine/convicine for faba bean only) were examined in a wide range of Canadian pulses. The total oligosaccharide concentrations were reduced ∼40% for chickpea, 11-81% for lentils, 41-43% for faba beans, 10-51% for beans, and 20-44% for peas. Individual oligosaccharides, raffinose, ciceritol, stachyose and verbascose, increased or decreased in the cooked samples depending on each pulse sample. Cooking reduced the total polyphenol content by 13-25% for chickpeas, 0-83% for lentils, 47-54% for faba beans, 47-54% for beans, and 48-70% for peas. And, the total saponin concentrations were reduced by 11-30% for chickpeas, 0-40% for lentils, 32-46% for beans, 14-30% for peas and increased by 8-26% in faba bean. The vicine and convicine levels in faba bean were reduced by 26-38% with cooking. The reduction in bioactive compounds after cooking depended on the specific compound and specific type of pulse. This large analyses of 20 different pulse samples allows for comparison between and within different types of pulses.

Reduction of off-flavours and the impact on the functionalities of lentil protein isolate by acetone, ethanol, and isopropanol treatments.

The changes of flavour profiles in lentil protein isolate (LPI) in response to organic solvent treatments (acetone, ethanol, and isopropanol; 35-95% v/v), and the resulting impacts on the isolate colour and physicochemical and functional attributes were investigated. The major constituents of volatile compounds were aldehydes (∼46.59%) and (E,E)-3,5-octadien-2-one (∼31.79%) in the untreated LPI. Acetone treatment greatly raised ketones by ∼79.59%. In contrast, ethanol and isopropanol, except at 95% (v/v), significantly lowered total volatile compounds and had higher protein contents (∼84.55%) than the others (∼76.98%); surface charge, surface hydrophobicity, solubility and emulsion stability of these LPIs were examined. LPIs obtained from 75% (v/v) ethanol and isopropanol treatments showed slightly lower solubility but improved surface hydrophobicity to produce emulsions with a similar stability as compared with the untreated LPI. Overall, ethanol and isopropanol treatments (75% v/v) produced high quality off-flavour-reduced LPIs which may be used in various food systems.