Germination alters the chemical composition and protein quality of lupin seeds

✍ Scribed by Suzanne G. Dagnia; David S. Petterson; Roma R. Bell; Frank V. Flanagan

• Publisher: John Wiley and Sons
• Year: 1992
• Tongue: English
• Weight: 392 KB
• Volume: 60
• Category: Article
• ISSN: 0022-5142
• DOI: 10.1002/jsfa.2740600403

✦ Synopsis

Abstract

The chemical composition and protein quality of the kernels from Lupinus angustifolius seeds were compared with that for sprouts after 6 days germination. Germination resulted in an apparent increase in protein content from 395 g kg^−1^ to 435 g kg^−1^ DM. Fat and carbohydrate contents decreased. The oligosaccharide content of the sprouted lupin fell to a negligible level, while the phytate and alkaloid concentrations fell from 4.7 g kg^−1^ to 1.6 g kg^−1^ and from 0.72 g kg^−1^ to 0.16 g kg^−1^, respectively.

The quality of lupin kernel protein was poor with a protein efficiency ratio (PER) of 1.45±0.15. Supplementation of kernel with DL‐methionine (2.0 g kg^−1^) increased the protein quality (PER = 2.87±0.17) to that of casein (PER = 2.86±0.18). Germination reduced protein quality (PER = 0.44±0.16), and did not improve apparent protein digestibility (APD kernel = 80.4%; APD sprout = 77.5%). Supplementation of sprout protein with DL‐methionine (2.0 g kg^−1^) increased the protein quality (PER = 2.57±0.20). The total sulphur‐containing amino acid concentration of lupin kernel protein, 1.9 g per 16 g N was low, and decreased further to 1.3 g per 16 g N in the sprout, a drop of 32%.

The results showed that germination of lupin seeds reduced the concentration of the anti‐nutritive factors; however, it also reduced protein quality.