Kinetics of solid-state fermentation of lupin with Rhizophus oligosporus based on nitrogen compounds balance. (August 2021)

• Record Type: Journal Article
• Authors: Villacrés, Elena; Rosell, Cristina M.
• Is Part Of: Food bioscience. Volume 42(2021)
• Publication Date: 2021-08
• Subjects: Protein digestibility -- Solid-state fermentation -- Lupin -- Legume nutrition; Food -- Biotechnology -- Periodicals; Food -- Research -- Periodicals; Aliments -- Biotecnologia -- Revistes; Aliments -- Investigació -- Revistes; Food -- Biotechnology; Food -- Research; Revistes electròniques; Periodicals; 664.005
• DOI: 10.1016/j.fbio.2021.101118
• Languages: English
• ISSNs: 2212-4292

Abstract

Abstract: Solid-state fermentation could be a potentially effective method for improving the nutritional value of legumes. The objective of this study was to explore this technology in Lupinus mutabilis, a species of lupin, using a strain of Rhizopus oligosporus mold for solid-state fermentation. Three L. mutabilis varieties (INIAP-450, INIAP-451, and Criollo) were evaluated, including the effect of the grain status (whole or ground) and integument or husk (presence or absence). Kinetic parameters of the fermentation process were studied to define the specific speed of nitrogen formation and the digestibility and nutritional quality of the resulting protein. After incubation at 28 °C for 96 h, the titratable acidity increased, the pH decreased, and the total nitrogen of the whole grain with integument reached 110 g kg −1 for the Criollo variety. The ground INIAP-450 grain without integument had the highest soluble nitrogen content, and nitrogen formation occurred at a specific rate of 0.006 h −1 . The apparent digestibility of the protein in this variety increased from 82 to 96% in debittered grain, the concentration of the first limiting amino acids (methionine + cysteine) increased from 20.8 to 27.9 mg g −1 crude protein, and the protein digestibility-corrected amino acid score increased from 68.3 to 89.3%. Overall, the results confirmed the benefits of fermentation in improving the content and quality of protein in the three lupin varieties. Highlights: Solid-state fermentation helped increase the nutritional value of the grain and the digestibility of its protein. The fermentation kinetics allowed establish the optimal time of the process. Fermented lupin has the potential to be used as a valuable food enricher and as raw material for health foods.