title: In-vitro digestibility and amino acid composition of soy protein isolate cross-linked with microbial transglutaminase followed by heating with ribose.
abstract: Cross-linked soy protein isolate (SPI) gels were produced via single-treatment of SPI with microbial transglutaminase (MTG) for 5 h or 24 h, or with ribose for 2 h, or via combined-treatments of SPI with MTG followed by heating with ribose. Assessment of gel strength and solubility concluded that measures which increased protein cross-links resulted in improved gel strength; however, in most cases the digestibility and amino acid content of the gels were reduced. The combined treated gel of SPI/MTG for 24 h/ribose was more easily digested by digestive enzymes and retained higher amounts of amino acids compared with the control Maillard gels of SPI with ribose. MTG consumed lysine and glutamine and reduced the availability of amino acids for the Maillard reaction with ribose. MTG was able to preserve the nutritional value of SPI against the destructive effect of the Maillard reaction and cross-links.
authors.affiliation: Food Technology Division, School of Industrial Technology, Universiti Sains Malaysia, Minden, Penang, Malaysia.
authors.forename: Chee-Yuen
authors.initials: CY
authors.lastname: Gan
authors.forename: Lai-Hoong
authors.initials: LH
authors.lastname: Cheng
authors.forename: Baharin
authors.initials: B
authors.lastname: Azahari
authors.forename: Azhar Mat
authors.initials: AM
authors.lastname: Easa
mesh_terms: D000596:Amino Acids / Q000032:analysis*; D019245:Compressive Strength; D004063:Digestion; D004151:Dipeptides / Q000378:metabolism; D005511:Food Handling / Q000379:methods; D005782:Gels / Q000737:chemistry / Q000378:metabolism; D005973:Glutamine / Q000378:metabolism; D006358:Hot Temperature; D008239:Lysine / Q000378:metabolism; D015416:Maillard Reaction; D010447:Peptide Hydrolases / Q000378:metabolism; D014674:Plant Proteins, Dietary / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D012266:Ribose / Q000737:chemistry*; D012995:Solubility; D030262:Soybean Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D013997:Time Factors; D011503:Transglutaminases / Q000378:metabolism*
chemical_list: D000596:Amino Acids; D004151:Dipeptides; D005782:Gels; D014674:Plant Proteins, Dietary; D030262:Soybean Proteins; D005973:Glutamine; C001299:epsilon-(gamma-glutamyl)-lysine; D012266:Ribose; D011503:Transglutaminases; D010447:Peptide Hydrolases; D008239:Lysine