Structural characteristics of alkaline treated fibers from date-pits: Residual and precipitated fibers at different pH. (May 2021)

• Record Type: Journal Article
• Authors: Al-Khalili, Maha; Al-Habsi, Nasser; Al-Alawi, Ahmed; Al-Subhi, Lyutha; Zar Myint, Myo Tay; Al-Abri, Mohammed; Waly, Mostafa I.; Al-Harthi, Salim; Al-Mamun, Abdullah; Rahman, Mohammad Shafiur
• Is Part Of: Bioactive carbohydrates and dietary fibre. Number 25(2021)
• Publication Date: 2021-05
• Subjects: Date-pits -- Cellulose -- Fibers -- Infrared fourier transform (FTIR) -- X-ray diffraction; Functional foods -- Periodicals; Fiber in human nutrition -- Periodicals; Carbohydrates -- Periodicals; Glycoproteins -- Periodicals; Functional Food -- Periodicals; Dietary Fiber -- Periodicals; Carbohydrates -- Periodicals; Carbohydrates; Fiber in human nutrition; Functional foods; Glycoproteins; Periodicals; 613.28
• DOI: 10.1016/j.bcdf.2020.100251
• Languages: English
• ISSNs: 2212-6198

Abstract

Abstract: Four types of fibers (i.e. defatted, F1; residue after alkaline digestion, F2; precipitated fibers at pH 5.5, F3; and pH 1.5, F4) were prepared from date-pits. The date-pits were first defatted and then digested by an alkaline solution. The fibers F2 showed the highest amount of cellulose (i.e. 46.0 g/100 g sample), while fibers F3 and F4 showed the lowest amount of cellulose (i.e. F3, 9.3 g/100 g sample). The visual structures of the fibers were determined by Field Emission Scanning Electron Microscope (FESEM). Fibers F1 (i.e. defatted date-pits) showed that lignin was coated over holocellulose, however alkaline digestion clearly showed lignin-coating was removed and fibers (F2) contained two main types of structural matrix (i.e. micro-size trapezoidal particles were embedded in nano-size fine interconnected fibers). Fibers F3 showed highly porous particles, while F4 showed that spherical particles were imbedded in an interconnected fiber matrix. Infrared Fourier Transform (FTIR) peaks within the wave number 500-4000 cm −1 showed different molecular structures of the fibers. X-ray (XRD) patterns showed different crystallinity of the fibers. The crystallinity of the F2 and F4 were 76.7 and 95.5%, respectively and fibers F3 was mainly amorphous in nature.