title: Relationship between digestibility and secondary structure of raw and thermally treated legume proteins: a Fourier transform infrared (FT-IR) spectroscopic study.
abstract: The secondary structure of proteins in legumes, cereals, milk products and chicken meat was studied by diffuse reflectance infrared spectroscopy in the region of the amide I band. Major secondary structure components (  β-sheets, random coil,   α-helix, turns), together with the low- and high-frequency side contributions, were resolved and related to the in vitro digestibility behaviour of the different foods. A strong inverse correlation between the relative spectral weights of the   β-sheet structures and in vitro protein digestibility values was measured. Structural modifications in legume proteins induced by autoclaving were monitored by the changes in the amide I spectra. The results indicate that the β-sheet structures of raw legume proteins and the intermolecular β-sheet aggregates, arising upon heating, are primary factors in adversely affecting the digestibility.
authors.affiliation: Istituto Nazionale di Ricerca per gli Alimenti e la Nutrizione, Via Ardeatina 546, 00178 Rome, Italy. carbonaro@inran.it
authors.forename: M
authors.initials: M
authors.lastname: Carbonaro
authors.forename: P
authors.initials: P
authors.lastname: Maselli
authors.forename: A
authors.initials: A
authors.lastname: Nucara
mesh_terms: D000577:Amides / Q000737:chemistry; D000818:Animals; D030161:Avian Proteins / Q000737:chemistry; D002417:Cattle; D002611:Cheese; D002645:Chickens; D004044:Dietary Proteins; D007887:Fabaceae / Q000737:chemistry; D001467:Hordeum / Q000737:chemistry; D006358:Hot Temperature; D008460:Meat; D008894:Milk Proteins / Q000737:chemistry; D010447:Peptide Hydrolases / Q000737:chemistry; D010940:Plant Proteins / Q000737:chemistry; D011489:Protein Denaturation; D055550:Protein Stability; D017433:Protein Structure, Secondary; D059748:Proteolysis; D030262:Soybean Proteins / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D014908:Triticum / Q000737:chemistry
chemical_list: D000577:Amides; D030161:Avian Proteins; D004044:Dietary Proteins; D008894:Milk Proteins; D010940:Plant Proteins; D030262:Soybean Proteins; D010447:Peptide Hydrolases