Characterization and effect of year of harvest on the nutritional properties of three varieties of white lupine (Lupinus albus L.)

BACKGROUND: Three cultivars of Lupinus albus L. (Lutteur, Lublanca and Multitalia) were assessed for proximate composition, fatty acids, alkaloids and in vitro fermentation characteristics over three harvest years. RESULTS: The chemical composition varied greatly during the three harvest years. Crude protein content ranged from 353 to 456 g kg-1 dry matter (DM), neutral detergent fiber content from 209 to 321 g kg-1 DM and lignin content from 3.0 to 63.9 g kg-1 DM. Lublanc showed the highest crude protein (417 g kg-1 DM) and lignin (35 g kg-1 DM) contents. High levels of lipids (89.9gkg-1 DM) and starch (93.3 g kg-1 DM) were found in all samples. Alkaloid content ranged from 3.63 to 165mg per 100g. Lutteur and Lublanc showed more favorable n-3/n-6 polyunsaturated fatty acid ratios (from 0.44 to 0.73) and lower values of the anti-quality factor 'erucic acid' (from 5.8 to 20.9 g kg-1) than Multitalia. Lutteur showed higher degradability (897 g kg-1), gas production (330 mL g-1 organic matter (OM)) and volatile fatty acid production (117mmolg-1 OM) than the other varieties. CONCLUSION: The present data suggest L. albus L. cv. Lutteur to be a promising crop as food thanks to its high nutritive traits and most constant yield over time.