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

BACKGROUND: Three cultivars of Lupinus albus L. (Lutteur, Lublanc, Multitalia) were assessed for proximate analysis, fatty acids, alkaloids and in vitro fermentation characteristics over three harvest years. RESULTS: The chemical composition fairly varied during the harvest years (g kg-1 Dry Matter): Crude Protein content ranged from 353 to 456, Neutral Detergent Fiber from 209 to 321 and lignin from 3.0 to 63.9. The Lublanc showed the highest Crude Protein (417 g kg-1 Dry Matter) and lignin (35 g kg-1 Dry Matter) content. High levels of lipids (89.9 g kg-1 Dry Matter ) and starch (93.3 g kg-1Dry Matter) were found in all samples. Alkaloid content ranged from 3.63 to 165 mg 100g-1. The Lutteur and Lublanc showed more favorable n-3/n-6 Poly Unsaturated 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 the Multitalia. The Lutteur showed higher degradability (897 g kg-1), gas (330 ml g-1 Organic Matter) and Volatile Fatty Acids (117 mmol g-1 Organic Matter) production compared the other varieties. CONCLUSION: Data suggest the Lutteur to be a promising crop as food thanks to its high nutritive traits and most constant yield overtime.