ABSTRACT
The amino acid constituents are linked to each other in a linear sequence via substituted amide bonds. Unlike the glycosidic bonds in polysaccharides and phosphodiester bonds in nucleic acids, which are single bonds, the substituted amide linkage in proteins is a partial double bond, which further underscores the unique structural property of protein polymers. This chapter discusses both desirable and undesirable effects of food processing on proteins. It describes the effects of heat treatments on chemical changes in, and functional properties of proteins. The diverse biological functions of proteins can be categorized as enzyme catalysts, structural proteins, contractile proteins, electron transporters, ion pumps, hormones, transfer proteins, antibodies, storage proteins, and toxins. The primary structure of a protein refers to the linear sequence in which the constituent amino acids are covalently linked through amide bonds, also known as peptide bonds. Quaternary structure refers to the spatial arrangement of a protein when it contains more than one polypeptide chain.
