Plant Foods for Human Nutrition

, Volume 58, Issue 3, pp 1–8 | Cite as

Effect of natural fermentation on protein fractions and in vitro protein digestibility of rice

  • Nabila E. Yousif
  • Abdullahi H. El Tinay
Article

Abstract

Changes in pH, titratable acidity, total soluble solids and protein of rice during natural fermentation at 37 °C up to 36 h were monitored. The pH of the fermenting material decreased sharply with a concomitant increase in the titratable acidity. Total soluble solids increased with progressive fermentation time. The crude protein content fluctuated during the first 24 h of fermentation but started to increase thereafter. Non-protein nitrogen was unchanged during the first 12 h of fermentation but increased sharply with progressive fermentation. The in vitro protein digestibility markedly increased as a result of fermentation. The increase in the globulin + albumin fractions constituted the most remarkable increase and were the major proteins in the 36 h fermented rice; the increase was up to 2.7 fold. The prolamin fraction, which was the minor fraction, the G1-glutelin and G2-glutelin fractions increased with progressive fermentation time. The G3-glutelin, which was the major protein fraction of unfermented rice, markedly decreased as a result of fermentation, while insoluble protein fluctuated during the fermentation process.

Fermentation In vitro protein digestibility Protein fraction Rice Solubility 

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Copyright information

© Kluwer Academic Publishers 2003

Authors and Affiliations

  • Nabila E. Yousif
    • 1
  • Abdullahi H. El Tinay
    • 1
  1. 1.Department of Food Science and Technology, Faculty of AgricultureUniversity of KhartoumShambatSudan

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