A Study Of The Chemical And Nutritional Characteristics Of An Experimental Canadian Sweet Lupin Variety

Summary

The lupin, a leguminous plant, is a potential oilseed crop in regions withtemperature climates. This plant contains toxic constituents which appear to bequinolizidine alkaloids. Attempts to breed a sweet lupin variety with lowerlevels of these alkaloids have been reported. This paper examines the chemicaland nutritional properties of an experimental lupin grown in Manitoba, Canadacompared to a bitter lupin variety. The experimental lupin variety contained 27.2 percent protein and 14.8 percent fat compared to 39.0 percent proteinand 10.7 percent fat for the bitter lupin . Amino acid composition indicateda low level of me thionine for both lupin s, while fatty acid analysis showedsimilar patterns with CIS: 1 being the predominant fatty acid together withhigh levels of Cl8:2 and Cl8:3. The level of alkaloids was similar for bothlupins. However, the nutritional study found the experimental lupin dietcompared favorably with casein with respect to PER and was significantly(P<0.01) higher than the corresponding bitter lupin. Based on the higher PERvalue the experimental lupin variety compared favorably with earlier studieson sweet lupins. It was apparent, however, that qualitative differences in totalalkaloids must account for the high PER in weanling Wistar rats fed theex perim ental lupin. The qualitative differences between the experimentalsweet and bitter lupin varieties requires closer examination in order to explainthe superior nutritional quality of the experimental lupin variety.