Rapid spectrophotometric and fluorimetric methods for monitoring nitrogenous (proteinaceous) compounds in cheese and cheese fractions: a review

This article reviews various techniques which could be used to quantify nitrogenous compounds (proteins, peptides and/or free amino acids) in cheese. Chemical (macro-Kjeldahl), spectrophotometric [ultra-violet, Hull, Lowry, dye-binding (Amido Black 10B, Bradford, erythrosin), ninhydrin, trinitrobenzene-sulphonic acid and o-phthaldialdehyde (OPA)]and fluorometric (OPA and fluorescamine) procedures are discussed. Many of these techniques are commonly used in cheese analysis, while others have not been applied to cheese.