Characterization of potato flavours: An overview of volatile profiles and analytical procedures

Potatoes may be cooked by several methods such as boiling, baking and frying; they are also used as an ingredient for numerous home-made and mass-produced foods like sticks, chips and other snacks. An important factor affecting consumer preferences of these products is their flavour, which is defined as the combined perception of aroma, taste and mouthfeel sensations. Flavour, and in particular the volatile profile of potatoes, has been widely investigated in the last few years, and complex patterns have been found. Although raw potatoes possess little aroma, more than 140 volatile compounds have been identified in boiled potatoes, whereas over 250 have been found in baked potatoes and more than 500 compounds have been isolated in French fries. Among these, many lipid oxidation and Maillard reaction products have been reported, together with smaller amounts of indigenous flavour compounds. Many extraction methods have been developed to characterize the aroma of potatoes, with the goal of reducing analytical detection limits, avoiding formation of artefacts during isolation and reducing analysis cost and time; among these are distillation techniques, solvent and direct solvent extraction techniques, static and dynamic headspace methods and solid-phase microextraction. As regard isolation and quantification of potato volatiles, gas chromatography-mass spectrometry and gas chromatography/olfactometry are frequently used. The analytical approach is often completed with the sensory evaluations. This review describes the flavour profile of the main forms of cooked potatoes, taking into account their mechanism of generation; extraction and analysis procedures are also considered, reporting both conventional and innovative methods.