Composition and protein quality of Lupinus mutabilis.
The chemical composition and the protein quality of three samples of Lupinus mutabilis (a raw, semi-sweet variety; cooked, water-extracted seeds; and alcohol-extracted oil cake) were studied. The protein content varied from 47.7% dry weight (raw seeds) to 65.3% (oil-cake). Compared to the FAO reference pattern sulfur- containing amino acids are first limiting. The water-extracted sample contained 26.9% oil and the polyunsaturated/saturated fatty acid ratio of 30 seed samples was 5.3. Alkaloid content of raw seed was high (3.3%), but could be reduced or nearly eliminated by water-and-alcohol extraction or plant breeding. Other anti-nutritive substances were present only in trace quantities. Protein quality measured as protein efficiency ratio (PER) gave low values for the non-supplemented lupin proteins (1.34 semi-sweet variety; 1.53 water-extracted seeds; 1.19 oil-cake; 3.09 casein), but the PER's were improved by the addition of 0.2% DL-methionine to the diets (3.05, 2.69, 2,81, respectively). Raw as well as processed lupin protein showed an excellent apparent digestibility (80.0-85.8%, casein 87.1%). Studies of net protein utilization (NPU) and biological value (BV) confirmed the importance of methionine supplementation, The true digestibility of 92% was equivalent to that of casein.
D000470:Alkaloids / Q000032:analysis; D000596:Amino Acids / Q000032:analysis; D007887:Fabaceae / Q000032:analysis*; D005227:Fatty Acids / Q000032:analysis; D006386:Hemagglutination Tests; D006856:Hydrogen Cyanide / Q000032:analysis; D009753:Nutritive Value; D009821:Oils / Q000032:analysis; D010940:Plant Proteins / Q000032:analysis*; D010946:Plants, Medicinal; D014361:Trypsin Inhibitors / Q000032:analysis
D000470:Alkaloids; D000596:Amino Acids; D005227:Fatty Acids; D009821:Oils; D010940:Plant Proteins; D014361:Trypsin Inhibitors; D006856:Hydrogen Cyanide