Dairy product quality using screening of aroma compounds by selected ion flow tube‒mass spectrometry: A chemometric approach

Selected ion flow tube-mass spectrometry (SIFT-MS) can be used to analyse the concentration of volatile compounds in the headspace over food samples. Utilising chemometric classifiers, the concentration of aroma compounds detected by SIFT-MS was used to differentiate products. Nineteen compounds most useful in differentiating a range of dairy products were identified from the results of classification and selected for the development of preliminary threshold models to distinguish acceptable products from those containing off-aromas. Product differentiation was used to select the compounds for the threshold models, because sensory panel analysis rarely detects off-aromas in the products being examined. Threshold models for these compounds in the different products were developed using the 95% percentiles for the concentrations of these compounds that sensory panels found to be acceptable. These models have been used successfully during routine analysis to distinguish good products from marginal or off-aroma products, thereby lowering the demand on sensory panels.